Model Engine Maker

Engines => Your Own Design => Topic started by: steamer on September 06, 2021, 09:47:00 PM

Title: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 06, 2021, 09:47:00 PM
This is the beginning of a new build!   A 1/4 scale Porsche 917  180 degree V12    or Flat 12.

This engine was instrumental in the victories for Porsche at Leman in 1970.    This engine also would go on to dominate in the CANAM series in the early 70's in its turbo form.  However, this build will be of the engine in the Leman endurance racer format as shown below.

Specifics:

Bore:  0.845"  ( 21.5mm)
Stroke:  0.692"  ( 17.6mm)
Displacement:  76.7 CC
Air cooled
Engine block   2 piece split at the crank for a right and left half per the prototype.
DOHC with 2 valves per cylinder with 12 individual heads sharing a common cam box.
Gear driven camshafts as was prototypical, with a timing Vernier at each camshaft
Camshaft:    Individual hardened inlet and exhaust cams pinned to a common shaft driven by a gear as per prototype.
Ball bearing Crank with hardened throws
Plain connecting rod bearings of 6.7mm diameter.
Pressure Lube
Scavenged dry sump
Carbureted  ( Original was fuel injected)
Ignition will be via glow plug for initial running and debug. 
Dual Distributors
Fuel    E85 Gasoline with synthetic oil mix

I'll be following the prototype where ever possible.   The output shaft will be prototypical, and be gear driven off the center of the crank..   The cooling fan and the distributors will be driven from the top counter shaft also driven from the center of the crank.

Features where I will be departing from the prototype

Connecting rods will be 7075 T6 Aluminum, with bronze bearings ( the originals were Titanium with shell bearings)

The crankshaft will be for the sake of durability and reliability be a ball bearing built up crank.    As popularized by Shilling.  The crank throws will be hardened A2 tool steel.

The Oil Pump and Scavenge Pumps:
The oil pump and scavenge pump were driven by a pair of spur gears off the lower output shaft and were mounted directly to the engine block and fed oil to the engine with internal passages.   This is the proper thing to do on an endurance racer.  The best way to avoid a broken oil line is to not have oil lines in the first place!    However, the only way to access these pumps, is to split the case.    For the sake of maintenance simplicity, I've elected to mount the pumps off the front of the engine, directly driven by the output shaft.   This will allow easy removal of the pumps.   
The output of the oil pump will feed 6 nozzles via a cross drilled hole in the left engine block.  These nozzles will be aimed at each connecting rod pair.
Scavenge will be taken from the sump from two sump pickups connected vis cross drilled holes in the right engine block.

Now running some oil in the fuel is a common way to lubricate the bottom end on 4 stroke Model engines.   That would preclude the need for a oil pump and a scavenge pump....but all of that will get sorted out once it's running.

I've made a start with the rotating assemblies.    I'll post up my progress shortly.

Link to the Design Thread.      https://www.modelenginemaker.com/index.php/topic,6259.0.html

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on September 06, 2021, 10:24:31 PM
And so another epic build begins. I for one, will be following each and every step. In some ways I feel very close to this one. Maybe it's next on my list.

Dont forget to reference your readers back to the 917 design thread from time to time.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on September 06, 2021, 10:27:06 PM
Carton of fresh popcorn: check

Comfy chairs for me and shop elves: check

bibs to control drool: check

Ready! :popcornsmall:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on September 06, 2021, 10:32:40 PM
Did you notice the caption on the second to last photo "porsche-917-racer-could-be-yours-for-a-cool-20-million.jpg ".

Now we can see why Dave is building his own, rather than buying

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 06, 2021, 10:40:43 PM
And so another epic build begins. I for one, will be following each and every step. In some ways I feel very close to this one. Maybe it's next on my list.

Dont forget to reference your readers back to the 917 design thread from time to time.

Mike

I can only imagine it's because you and I have been talking about the design of it for 5 years!! :cheers:

Life certainly got in the way of this one....My daughter's cancer....twice!.....the surgical reconstruction of my right quadricep, and a global pandemic!......  There!   that's three!  NO MORE.

 8)

Dave


Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 06, 2021, 10:42:18 PM
Did you notice the caption on the second to last photo "porsche-917-racer-could-be-yours-for-a-cool-20-million.jpg ".

Now we can see why Dave is building his own, rather than buying

Mike

And it's only affordable because it's only the engine...and it's 25 percent full size!!! :DrinkPint:

oh and one other thing....I pay the guy building it in beer....when he's not doing other things.....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 06, 2021, 11:03:53 PM
OK so currently I'm rejiggering the program to cut multiple parts by order of tools

There are 6 or so tool changes per part, if I do one part at a time, and I have 5 more parts that 30 tool changes...but if I cut more than one at a time....it's only 6 tool changes...and I can do something else in between....like crank pins.....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Johnmcc69 on September 06, 2021, 11:26:19 PM
Woo Hoo! Here comes the chips!
 Glad that everything's coming together Dave, it's going to be a really great build to follow!
 :popcornsmall:
 :cheers:

 John
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 07, 2021, 12:05:38 AM
Thanks for coming along John!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 07, 2021, 12:44:24 AM
OK   8 tool changes per piece....or 8 total for 3 parts......

Just need to make a new base fixture, I think 3 at a time is a good place to stop...it's a 1.5 hour process for three


Oh and a little eye candy......a print and that print superimposed on the CAD model

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 07, 2021, 01:19:50 AM
And some more views of the CAD assembly model

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Don1966 on September 07, 2021, 02:35:07 AM
Ok Dave we are with you and want to see the chips flying …….LOL…..



 :cheers:
Don
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: petertha on September 07, 2021, 03:09:40 AM
Here we go!
Maybe you spoke to this is the design workup but what materials were used in FS engine for the various (I'll loosely call them composite / molded thermoplastic) components. They all have different color amber shades, perhaps heat aging affecting them differently? Or maybe Kevlar used back then? The fan shroud has a hint of fabric so presume its a composite layup vs molded? Will you similarly miniaturize these?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Art K on September 07, 2021, 03:28:43 AM
Dave,
This should be a good build I'll be following along, and try to keep up.
Art
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on September 07, 2021, 03:32:25 AM
Hey guys, pass the popcorn, I have a front row seat

 :popcorn: :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 09, 2021, 12:55:45 AM
Here we go!
Maybe you spoke to this is the design workup but what materials were used in FS engine for the various (I'll loosely call them composite / molded thermoplastic) components. They all have different color amber shades, perhaps heat aging affecting them differently? Or maybe Kevlar used back then? The fan shroud has a hint of fabric so presume its a composite layup vs molded? Will you similarly miniaturize these?

Honestly....I haven't gotten that far yet....I have looked at those parts and honestly I think they are Kevlar/polyester resin layups.    I think I will probably 3D print some of these parts...

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on September 09, 2021, 11:29:26 AM
Here we go!
Maybe you spoke to this is the design workup but what materials were used in FS engine for the various (I'll loosely call them composite / molded thermoplastic) components. They all have different color amber shades, perhaps heat aging affecting them differently? Or maybe Kevlar used back then? The fan shroud has a hint of fabric so presume its a composite layup vs molded? Will you similarly miniaturize these?

Honestly....I haven't gotten that far yet....I have looked at those parts and honestly I think they are Kevlar/polyester resin layups.    I think I will probably 3D print some of these parts...

Dave

Hi Dave and perertha,

I think you will find that the fan, the shroud and the injection trumpet decks were dough moulded using the DMC process, rather than a layup. DMC (Dough Moulding Compound) was a popular material for aerospace products in the 1970's 1980's. The DMC is an uncured dough-like thermoset compound, made up from either epoxy or polyester resins with a high proportion of chopped E glass fibre and other fillers.

The DMC process requires expensive heated metal moulds and some form of a mechanical or hydraulic press to close the mould. Similar in some ways to die casting moulds.

A measured amount of uncured dough moulding compound is rolled flat and placed into the heated female mould. The heated male side of the mould is closed, under pressure, forcing the dough molding compound into the mould cavities. Heat from the mould initially softens the dough molding compound so that it flows into every part of the mould very accurately. The heat then cures the compound.

The resulting material is both strong and light with the characteristic translucent amber colouring, you see on the 917 engine. The fibres are usually visible within the resin. The amber coulour seems to darken and become more opaque with age.

Sounds like a 3D print is the way to go. It would be nice to find a translucent amber printing filament to complete the illusion

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 10, 2021, 12:28:00 AM
Here we go!
Maybe you spoke to this is the design workup but what materials were used in FS engine for the various (I'll loosely call them composite / molded thermoplastic) components. They all have different color amber shades, perhaps heat aging affecting them differently? Or maybe Kevlar used back then? The fan shroud has a hint of fabric so presume its a composite layup vs molded? Will you similarly miniaturize these?

Honestly....I haven't gotten that far yet....I have looked at those parts and honestly I think they are Kevlar/polyester resin layups.    I think I will probably 3D print some of these parts...

Dave

Hi Dave and perertha,

I think you will find that the fan, the shroud and the injection trumpet decks were dough moulded using the DMC process, rather than a layup. DMC (Dough Moulding Compound) was a popular material for aerospace products in the 1970's 1980's. The DMC is an uncured dough-like thermoset compound, made up from either epoxy or polyester resins with a high proportion of chopped E glass fibre and other fillers.

The DMC process requires expensive heated metal moulds and some form of a mechanical or hydraulic press to close the mould. Similar in some ways to die casting moulds.

A measured amount of uncured dough moulding compound is rolled flat and placed into the heated female mould. The heated male side of the mould is closed, under pressure, forcing the dough molding compound into the mould cavities. Heat from the mould initially softens the dough molding compound so that it flows into every part of the mould very accurately. The heat then cures the compound.

The resulting material is both strong and light with the characteristic translucent amber colouring, you see on the 917 engine. The fibres are usually visible within the resin. The amber coulour seems to darken and become more opaque with age.

Sounds like a 3D print is the way to go. It would be nice to find a translucent amber printing filament to complete the illusion

Mike

Thanks for that Mike....this pesky work thing slows down my response!....That's an interesting note on the DMC process that I did not know about.   As far as 3D printing, I'm certainly at the right place to find a substitute material to replicate that.    I have a few materials in mind that I could use, but I'm also aware that not everyone has access  to those materials, so I may come up with something more readily available......I think I have some time to think that one over. 8)

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Art K on September 10, 2021, 09:06:16 PM
Mike,
Thanks for the info about DMC. It's above my pay grade I'm sure.
Art
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on September 10, 2021, 09:39:12 PM
DMC moulding fell out of favor when carbon fibre pre-preg became widely available.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 12, 2021, 01:42:16 AM
Ok...I got some time in the shop finally   More crank disk "B"s and I cut the crank pins.    The  pins need to be drilled and finished to length

When I inspected my first crank disk, I found it was out of spec, so I'll need to crank out 1 more tomorrow.

progress!!
 

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on September 12, 2021, 10:59:01 AM
More nice bits :ThumbsUp: :ThumbsUp:

Even with the best CNC machines, there can be slight tolerance differences between otherwise identical components. For critical components, like this built-up crankshaft, it can pay to make an additional one or two. You can then chose the very best, the cream of the cream,  for the final assembly.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: ozzie46 on September 12, 2021, 12:10:56 PM
Ok...I got some time in the shop finally   More crank disk "B"s and I cut the crank pins.    The  pins need to be drilled and finished to length

When I inspected my first crank disk, I found it was out of spec, so I'll need to crank out 1 more tomorrow.

progress!!
 

Just don't get cranky about it. :facepalm:

Ron
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 12, 2021, 12:31:25 PM
Yup  made 8   need 6    I have another blank and it's still set up..

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on September 12, 2021, 01:13:54 PM
Yup  made 8   need 6    I have another blank and it's still set up..

Dave

Need 6?? I guess that's 6 side A and 6 more side B

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 12, 2021, 02:04:03 PM
There are 4 B sections   and 2 A sections

Each A and B section has a finished side and a unfinished side  ( bearing diameter)

One side is finished in that the ball bearing diameter and mounting face are machined complete prior to assembly


The other unfinished side has the ball bearing diameter and face machined AFTER the section has been assembled to the crank pin  to guarantee concentricity

It's How Shilling did it actually.

The area in blue is finish machined after the 3 parts are put together either with loctite or just the press fit

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on September 12, 2021, 02:27:17 PM
Glad to see you underway with this one  :) I will be following along  :wine1: :wine1:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on September 12, 2021, 06:52:46 PM
I'm following along, Dave, but I don't have much to add.

Other than to say, "that is one complex crankshaft!  Wow!"    :popcorn:

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 12, 2021, 11:40:16 PM
Well....it's no Briggs and Stratton!.....I started with what I think is the most difficult part of this build.   The Crankshaft.    As the power from this engine is taken from the center by way of a big gear, and a 8 main ball bearing crankshaft.....it's a doozy!...I figured if i could build this....I can build it!

I'm putting together a post from today's effort....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 13, 2021, 01:13:32 AM
Made more cranks today, and all the crankpins.  The Crankpins are A2 tool steel.   The will be hardened.   The crank webs are 1144SP.     To test the press fit I made up a extra pin and cheek and pressed them together  ( .002" press fit") using some never seize as a lubricant.   It worked perfectly!   So I'll just keep going this week and see how many I can get done.   I need to order some more 1144SP to finish off the parts for the crank, including the central gear.  #2 and #4 32 DP cutters and a arbor.....lots of tool making this week I think.    I'm having fun with it thou.      I was able to save that oversize crankweb, so I have my 4 and they all meet spec.

Progress!

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on September 13, 2021, 03:19:31 AM
Looking great! I can hear the satisfaction loud and clear in your post.  :ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 15, 2021, 12:32:15 AM
Ok  had an epiphany, and it resulted in reduced set up and machine time...light dawns over marble head...anyway I'll be finished with half the crank webs tonight....and then I can start the rest.  I'll order gear cutters tomorrow.  32Dp and 48 Dp    14.5 degree PA  and the rest of the stress proof.   I also ordered some ttstool holder blanks to make cutter arbors from.    As cheap as the steel id make them out of.  Starting to get some momentum here.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 15, 2021, 02:59:26 AM
A cranks done with a spare   In the middle of making the holding fixture for the Bs.

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on September 15, 2021, 03:40:12 AM
What was the epiphany?  Pictures!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 15, 2021, 05:23:24 AM
 :lolb:  Instead of having a finished and unfinished A and B, I changed the assembly to a finished A side and a unfinished B side.  That means 2 set ups instead of 4 set ups.....so significant..

My biggest challenge this evening was ME!    Did some dumb things and broke tools....but I didn't lose parts! so I got there eventually!
I need to arrange to have the crankpins hardened....

Finished A sides on the left.   Unfinished B sides on the right


Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on September 15, 2021, 08:47:42 PM
Lots of parts !  I assume you have some type of assembly jig planned to keep everything square?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 16, 2021, 12:59:36 AM
Lots of parts !  I assume you have some type of assembly jig planned to keep everything square?

Thanks for looking in Craig

Yes    There will be 2.   One to press the B side onto the assembly, to keep is close to aligned, and a second one to hold the A side while I machine the bearing diameters on the B side to size and concentric to the A side.

After that.   It's all about stringing all the sections together into a single crankshaft just like stringing together beads.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 16, 2021, 01:54:00 AM
I don't think I've explained how this crank gets made very well, Shilling was quite clever!    His design allowed for some very high power outputs, with a fairly simple crank design.   It requires careful work, but it's doable

Hi approach was to create a ball bearing crank via many small pieces     If allows for large ball bearing mains, and also can provide for a ball or roller bearing connecting rod bearing as well.    If you've ever been into the bottom end of a modern 2 stroke or even 4 stroke motorcycle engine, you have seen this construction before.

So what I'm doing, is creating 2 crank webs, and a crank pin.   The A side has M4 threaded holes, while the B side has M4 clearance holes
The crank pin fits with a interference fit.   Seems simple right?

But how to you make sure that the two bearing diameters are concentric?   And it NEEEDS to be concentric!
There are 8 main bearings on this crankshaft,

One way that Shilling did it was to machine one side complete, assemble the 3 parts, and then FINISH machine the second side using the finished side as a datum both radially and axially.

Rinse and repeat 6 times.....plus a gear....and some end caps....and you have a 917 crankshaft

It's slow going as there are quite a few parts to make, but it seems to be coming together quite nicely.   I'm still torn as to finishing the second side in the lathe, with a fixture, or in the mill with some soft jaws to hang on to it.      but I'll figure that out when I get there.     

The OD and FACE in blue below are the two surfaces that get finish machined after assembly to assure concentricity....I've left material on the second web specifically for this purpose.

I am going with ball bearing mains 32 x 25 x 4, and bronze bearings on hard pins for the rod bearings.   Simple, and hopefully durable.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on September 16, 2021, 02:00:03 AM
Thanks. That does help to clarify what you're up to. And what you're up against! :ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 16, 2021, 02:04:01 AM
Thanks Ron,

I think it's the best way forward.   Making that crank any other way would be daunting!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Art K on September 17, 2021, 01:31:52 AM
Dave,
I have been following along just not saying much/anything. I do have one thought though.
Quote
Making that crank any other way would be daunting!
As if doing it this way isn't daunting!
Art
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 17, 2021, 10:57:44 AM
Well   you can do (1) 6 throw  crank...or (6)  1 throw cranks....like I said if I can.make this crank...I can make the engine.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 17, 2021, 11:45:07 AM
Additionally...cutting the center gear on a solid crank would be tough without a gear hob.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 19, 2021, 07:44:20 PM
B sides underway!   I think The program is good now....now to run 6 good ones

Plug gage fits just a scouch tight, but alright
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 20, 2021, 01:13:32 AM
Ok   Progress!     Other than 18 holes to tap M4, and general deburring, the crankwebs are done with spares.!   The crankpins are also done with spares and I'm setting up now to get them heat-treated.   Lot of work there!....next is assembly fixtures, and gear cutting.  The 917 engine took power from a gear at the center of the crank.   I have some cutters coming.....fun  challenging project!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on September 20, 2021, 09:39:02 PM
Right on! I guess once everything is assembled you will know if you are good?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 21, 2021, 03:56:19 AM
Hey Bubba!    thanks for dropping by.

Right on! I guess once everything is assembled you will know if you are good?

Almost!!!   

In the first photo below....
the crank cheeks to the left are finished....

The crank cheeks to the right have the bearing diameters left large

Once the crank pins are hardened,  they will be installed in all the crank cheeks to the left..

THEN....all the right cheeks will be pressed on and oriented to match the left ones as close as possible.

See the second photo

Next...the semi finished crank is mounted in lathe fixture.    the fixture locates the left crank directly on center of the lathe.

Then....we finish turn the bearing diameter of the right hand crank disk  IN SITU, which results in two concentric diameters!

Then I'll bolt all these together and we have a crank!

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on September 21, 2021, 03:59:24 AM
Quote
Then I'll bolt all these together and we have a crank!


you make it sound so easy!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 22, 2021, 12:07:08 AM
Quote
Then I'll bolt all these together and we have a crank!


you make it sound so easy!

It's labor intensive    YES.   Particularly difficult?    NO  I don't think it is!!!!

All these parts could have been done on a Sherline manual lathe and mill.  Is there a lot of parts?   Sure!   But it spreads the risk out.    Imagine cutting a 6 throw 7 main bearing  crank with a gear in the middle in a home shop from the solid on a Sherline or any other lathe for that matter!    This solution really helps make building this engine feasible.   The crank pins are precision ground A2 round stock. Right out of McMaster!
I part to length, face the ends and drill a hole through them.     Harden and polish the ends and they're done.   you have 6 crank pins all within 8 microns of each other....Thank you Mcmaster Carr!


The crank disks are fussy in three dimensions.   But it's simple turning and boring, and the way the crank is built up, you get several chances to correct errors as you go.  Most of the crank dimensions are +/- .005" which most can hold without too much difficulty.   the rest can be jig positioned

The assembly will be about some assembly fixtures and an arbor press.   Most here have the press, and can make simple fixtures...which if you're going to be making engines, you better get used to it....you make lots of fixtures!!!!!

No I don't think it's that bad....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 25, 2021, 02:05:09 PM
Gear cutters and arbors are here!!! :whoohoo:

I'll post up what I get up to,    once I can cut the 3 primary gears, and get the pins hardened at Cletus's Heat treat Haven.....I can get on with the rods perhaps....

Gonna go where I see fun to do next.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on September 25, 2021, 05:32:56 PM
Dave, it's always fun when new tools arrive!  :LickLips:

Can't wait to see what you do next!  :popcorn: :popcorn:

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 25, 2021, 07:05:49 PM
Hey Kim

Thanks for following along.   Today's exercise will be mostly tool making and I may just post it to the tools section till I'm cutting-edge gears...

Thanks again for your interest..someone is reading it.     :ThumbsUp::ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on September 25, 2021, 09:08:36 PM
Were all reading it!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on September 26, 2021, 12:31:24 AM
Hey :cartwheel: I’m here.  Just stepped out to refresh the popcorn. :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on September 26, 2021, 02:05:44 AM
I never miss an episode.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 26, 2021, 03:15:54 AM
Ok   I really wanted to cut some gears for the 917 model  Got a Tormach arbor blank, got the gear cutters..   made the arbor from the blank.  Needed  1/2-20 tap..my two taps are dull, ok I'll single point them on the lathe.   Don't have a bolt with that tread..ok I'll go to the hardware store in the morning...let's get the gear blanks ready!    I'm out of material!!!!....sigh    :zap: :hammerbash: :Doh:....I'll get on the conrods tomorrow, and send the crank pins out to Cletus for heat treat...... :facepalm2: :wine1:
I may salvage something from this weekend.....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 26, 2021, 03:39:08 AM
OK  conrods.    The conrods on the prototype had nuts on the opposite face... ( see pictures one)

I'm going to try and duplicate that ....

It turns normal conrod build process on it's head a little...but shouldn't be too bad..   and yes    I DO have the material for the rods.!!! :facepalm:

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on September 26, 2021, 04:55:06 PM
Looking good  :ThumbsUp:  :ThumbsUp:  :wine1:

I've made some conrods that way round. It's the easier way (the only way??) to assemble and engine with a tunnel crankcase.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 26, 2021, 08:46:14 PM
Looking good  :ThumbsUp:  :ThumbsUp:  :wine1:

I've made some conrods that way round. It's the easier way (the only way??) to assemble and engine with a tunnel crankcase.

If you put all the rods on first, you can do it conventional
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on September 26, 2021, 09:49:16 PM
 :popcorn: :popcorn: :popcorn:   
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on September 27, 2021, 02:08:42 AM
Not a real productive weekend boys and girls..     i was able to make the arbor...check... I think I'll be fine with the gear cutter....god I hope so...

But NO MATERIAL>      I could have sworn I had a good foot of 1.5" 1144 sp......but I didn't ......

SO

I started on the con rods   I did the programing and it became apparent that the inverse screw location was a PITA!     So I flipped it as I was sure I could put this all together in the end.      Then I spent some time programing the conrods...and probably in pairs...which is where I left off ....mean while I've had a few doctor trips for my Daughter,   and the honey do...so It's been less than Crueby levels of progress.....but I did watch Lemans last night as I tried to get myself to sleep....good movie.....Love the main character!..... 8)

Cletus You'll be gettin a package shortly
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Johnmcc69 on September 28, 2021, 12:39:06 AM
 :ThumbsUp:
 :popcorn:

 John
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 04, 2021, 03:20:23 AM
Connecting rod blanks going through Op 1.  Rod bolt holes. 
After that, then the cap is machined and parted off, and then bolted back on and finish machined.....1 in the machine and 11 more waiting their turn

Meanwhile, Cletus has started the heat treat process!    :whoohoo:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on October 04, 2021, 12:01:04 PM
It's probably just me .... but unless it's a test piece in the oven, I'm not getting it  :headscratch:

Looking forward to see how you hold those blanks while the CNC does it job  :cheers:

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 04, 2021, 03:24:29 PM
Yes Eric is testing a coupon part to verify the process for 57Rc.   

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Jasonb on October 04, 2021, 04:04:57 PM
Good way to contour the caps and part them off in one go, avoids the bolt heads getting in the way if you do the contour on the whole part.

Will you tap in the CNC or don't you have that facility as I noticed you did not seem to do it for the crank webs.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Don1966 on October 04, 2021, 05:45:33 PM
Still with you Dave but I didn’t know Eric had a hardness tester….. :Love:



 :cheers:
Don
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 04, 2021, 08:24:28 PM
Good way to contour the caps and part them off in one go, avoids the bolt heads getting in the way if you do the contour on the whole part.

Will you tap in the CNC or don't you have that facility as I noticed you did not seem to do it for the crank webs.

Thanks Jason     my thoughts exactly.  Uses less material as well.

Holes are deep so a pecking pass is in order as well as doing the cobores first.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on October 04, 2021, 10:03:26 PM
Quote
I think you can see the stainless steel wallet used to prevent oxidiation of the item being heat treated.

Oh yes - that trick I've heard about before  :ThumbsUp:  - but as I have never hardened anything (on purpose) .... it didn't show up in my ready memorybank  :-[
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 05, 2021, 02:23:31 AM
"Will you tap in the CNC or don't you have that facility as I noticed you did not seem to do it for the crank webs.?


No I dont have rigid tapping capabilities, but 7075 T6 is pretty easy to tap.

The only down side to doing the cap this way is the drilled holes are deep and blind.   Gotta go easy  and let the chips come out.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on October 05, 2021, 11:13:37 AM
Dave - I'm sure that your CNC can do 'single point threading' and I would be rather surpriced if it isn't good at it .... but of course it requires the right Tool in the holder + G-Code.

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 05, 2021, 11:17:07 AM
Hi Mike    I use the canned peck full retract as well.   10 dia deep is still deep....but I just let it do its thing

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 05, 2021, 01:02:40 PM
My machine will thread mill, but as thread mills are expensive and I have taps...I'm going to keep it simple.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Jasonb on October 05, 2021, 04:23:55 PM
I think Andrew who also has a Tormach uses a tapping head together with spiral flute or point taps and can run them at about 500rpm in aluminium at M2 or M3 sizes. Biggest advantage is that they will be nicely lined up under the spindle.

I usually just use F360s pecking option for deep holes
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 09, 2021, 03:57:10 PM
Whiskey has been hard at work doing some heat treating   crank pins in the furnace and quenching

Dave


PS   I think he has some splainin to do regarding that fly press!

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 09, 2021, 06:37:40 PM
Op 1 on the rods is done!!   Now I have 24 tapped holes and some rod bolts to make and we can profile and part off the caps and then finish the rod as an assembly
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on October 09, 2021, 07:06:58 PM
Whiskey has been hard at work doing some heat treating   crank pins in the furnace and quenching
(https://www.modelenginemaker.com/index.php?action=dlattach;topic=10504.0;attach=129230;image)
Dave
PS   I think he has some splainin to do regarding that fly press!

Do you know if Whiskey quenches the bits while they are still in the stainless steel wallet, or are they removed first?

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 09, 2021, 07:14:30 PM
Whiskey has been hard at work doing some heat treating   crank pins in the furnace and quenching
(https://www.modelenginemaker.com/index.php?action=dlattach;topic=10504.0;attach=129230;image)
Dave
PS   I think he has some splainin to do regarding that fly press!

Do you know if Whiskey quenches the bits while they are still in the stainless steel wallet, or are they removed first?

Mike

He kept the first on in the pouch.    60 to 65 Rc..before tempering......harder than woodpecker lips!    He's going to draw the temper now....A2 air hardening

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on October 09, 2021, 11:58:04 PM
Whiskey has been hard at work doing some heat treating   crank pins in the furnace and quenching
(https://www.modelenginemaker.com/index.php?action=dlattach;topic=10504.0;attach=129230;image)
Dave
PS   I think he has some splainin to do regarding that fly press!

Do you know if Whiskey quenches the bits while they are still in the stainless steel wallet, or are they removed first?

Mike

He kept the first on in the pouch.    60 to 65 Rc..before tempering......harder than woodpecker lips!    He's going to draw the temper now....A2 air hardening

Huh... that's interesting. I'd think it would be harder to cool the parts quickly if they're still wrapped in the stainless... Very interesting!
Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 01:14:47 AM
Ok   7 rods done tonight  I'll do the others tomorrow as I run 3rd op.   While I was in the shop I mad a Joe Pieczynski small tap wrench its nothing more than what you see.  1 inch OD by .350 wide with a 0.144 hole thru and a 10-32 sets crew.   It works amazingly well for stuff from 4-40 down.   Got to give the new vice a workout too!....sweeeeeet!
Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on October 10, 2021, 06:16:15 AM
Very nice, Dave!  That is a cute little tap handle.  I may have to make one of those.  I really like my little red tap handle, but I can see having a round knob like that could be really nice :)

And excellent use of the Piper Vise!  Extra credit for that! :ThumbsUp:

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on October 10, 2021, 09:47:16 AM
To make the tools to make the parts  :)  :)  :)  :praise2:  :wine1:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 02:45:15 PM
Very nice, Dave!  That is a cute little tap handle.  I may have to make one of those.  I really like my little red tap handle, but I can see having a round knob like that could be really nice :)

And excellent use of the Piper Vise!  Extra credit for that! :ThumbsUp:

Kim

Joe recommends wire brushing the knurls after as they can be a bit rough on the fingers....I would second that advise!   But I really like it..and I had the tool made and dusted in literally 10 minutes.....Going right into the tool box after.

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 02:51:00 PM
To make the tools to make the parts  :)  :)  :)  :praise2:  :wine1:

Thank you Roger......It is very satisfying ....to say nothing of making tools on a lathe I completely rebuilt from "boat anchor" status....nearly 10 years ago.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Don1966 on October 10, 2021, 04:49:50 PM
Putting that new vise to work I see buddy. ……… :Love:



 :cheers:
Don
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on October 10, 2021, 05:14:11 PM
Screw the tap holder! Where is the picture of the rods!! We want to see the good stuff! :Lol: :Lol:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 05:32:04 PM
Screw the tap holder! Where is the picture of the rods!! We want to see the good stuff! :Lol: :Lol:

 :lolb:    Bubba want nice Rods!!!!!!    :lolb:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 08:08:00 PM
OK Bubba!    3rd operation done on rods.   Profile the rod cap and part off, then finish cut the rod bolt face.  I need to work on part organization.   Especially when dealing with 12 each!   I had dozens or part sorter boxes while William and I were racing....do you think we'd have ONE I could use?    :ShakeHead:

I'll buy some more, but I cleared out the bottom 3 rows of drawers of this hardward sorter for the moment.   

In each is the embryonic rod, and the profiled, but not yet brought to thickness rod cap, with orientation marking  so the can go back together.    Now I looked at my screw assortment last week and said I have plenty of 4-40 grade 8 screws.........I was wrong.......they're M3's....... :facepalm: :hellno:

So Op 4 ,   bolting the parts back together and bringing to thickness will need to wait a couple of days.........
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on October 10, 2021, 08:36:05 PM
If you have a container store near by stop and get you some stackable divided trays. They are great for the long term projects and ones with a lot of tiny parts. Sound fimiliar?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 08:46:41 PM
YUP    the RC community has brought it to a level of art form....because of all the traveling many do...it all needs to get packed tight

....but they're expensive...I like yours better for engine building

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on October 10, 2021, 08:57:43 PM
I've got a bunch of those boxes, great for all the small fastener sizes. I've found the cheapest good ones are at the fishing tackle aisles in the sporting goods stores - lots of variety of size combinations. I write in the fastener size with a fine tip permanant marker. Not very permanant, a little alcohol (not the drinking kind, that would be a waste! ) on a tissue cleans it off when I want to change it.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on October 10, 2021, 09:10:15 PM
Never thought of the fishing stuff aisle. I will have to check it out.


Dave those look expensive with all the individual little boxes. The trays I showed are not as good for travel but my project aint going nowhere. Much cheaper, but still not cheap.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 09:13:42 PM
I'm down with that Steve....They're top quality and all, but man are they proud of them!....

When I bought my first 2 of those RSC boxes....the pair was $56.....

The price seems to have dropped a bit over the years

https://rsrc.biz/en/rsrc-products/1180-pama-box-56-compartments.html

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 09:15:46 PM
Some honey do's today, and then back in the shop....I'm going to work out the cutting of the main drive gear so I have it when Eric is done with the crank pins

Should be interesting

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 09:16:53 PM
Whiskey has been hard at work doing some heat treating   crank pins in the furnace and quenching
(https://www.modelenginemaker.com/index.php?action=dlattach;topic=10504.0;attach=129230;image)
Dave
PS   I think he has some splainin to do regarding that fly press!

Do you know if Whiskey quenches the bits while they are still in the stainless steel wallet, or are they removed first?

Mike


Correction!!      I spoke with Cletus, and he did take the pin out of the bag for quench.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on October 10, 2021, 11:30:35 PM
Dave,
Harbor Freight has several of those kinds of storage solutions for a pretty reasonable price.  The fishing tackle boxes Chriss is talking about are usually made by Plano.  HFs are not nearly as nice, but they're good enough (I've got a bunch of both) and they're less than half the price of the Plano.

They also have something kind of like your previous picture.  Again, I'm sure it's quite a step down in quality, but it's only $6, and I'm betting it would hold parts.
https://www.harborfreight.com/24-container-storage-box-90243.html (https://www.harborfreight.com/24-container-storage-box-90243.html)

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 10, 2021, 11:41:10 PM
Thanks Kim!!  I'll order some up!!!
Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on October 11, 2021, 12:13:14 AM
Bass Pro Shops/Cabellas (same company these days) have good ones too in store brand:
https://www.basspro.com/shop/en/utility-boxes#facet:&productBeginIndex:0&facetLimit:&orderBy:&pageView:grid&minPrice:&maxPrice:&pageSize:&
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: 90LX_Notch on October 11, 2021, 02:10:01 AM
I wouldn’t call that a Joe Pie tap holder.  I made one at least 5 years ago after seeing a post that Marv made.  I’d call it a Marv tap holder.


-Bob
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 17, 2021, 11:11:08 PM
OK   Some progress this week...no where near enough, but I've had to work the weekend, and late all last week, so it is what it is.

I have all the material I need for the Crankshaft and the connecting rods.    Cletus delivered my crank pins, right where I asked them to be at  52 Rc.  and as so tempted as I was , I've avoided pressing one in yet.   I need to lap and polish them first.

For the crank
I need an assembly fixture to align the second crank at least close to the first.   that may be made up with a 123 block...
I need to make a fixture to hold a crank section while I finish machine the B side crank.   
I need to machine the center drive gear.   I have the cutters and a cutter arbor.
I need to machine the crank end bell shaft sections....easy peasy...

Connecting rods
I need to bore them to size
I need to fixture them on the bores
I need to profile them to shape

Big end bearings.
I have the material....it should be straight forward.

I was able to get some organizers at Horror Fright...I bought them out!    Nice to have a place to put things and it's amazing how many parts I'm into already

I should have some time later in the week...and I'll take advantage of that.

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: tghs on October 18, 2021, 01:45:25 AM
I have found these boxes work well, the adjustable bins help a great deal..
https://www.homedepot.com/p/HDX-15-Compartment-Interlocking-Small-Parts-Organizer-in-Black-2-Pack-320034/204515485?source=shoppingads&locale=en-US&&mtc=Shopping-B-F_D25T-G-D25T-025_011_STORAGE_DEVI-Multi-NA-Feed-PLA-NA-NA-StorageDevices_SmartShopping&cm_mmc=Shopping-B-F_D25T-G-D25T-025_011_STORAGE_DEVI-Multi-NA-Feed-PLA-NA-NA-StorageDevices_SmartShopping-71700000081401733-58700006882766023-92700061894095921&gclid=CjwKCAjwk6-LBhBZEiwAOUUDp97xjDDnMOKzQnEu3rPXnuQxPC0x3f3UzPv889pnneRPZW0bns2CQRoCKlYQAvD_BwE&gclsrc=aw.ds
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 23, 2021, 06:23:27 PM
Some progress photos!    I could not help but put one crank section together, and wow I was worried about nothing!   The procedure is thus.  Make a guide block so you can start to press the pin home squarely.   It's just a block with a close fitting hole that matches the crank pin.   Press the pin home into the A side crank, which is a finished part.  .  Take off the block and put aside.  Line up the raw machined crank side B and tap onto the crank pin lightly (.0015 to .002 press fit on a 7mm pin).  Set the finished side down and check the two crank disks for alignment with a square.  Tap the raw one around until it lines up on both crank disks.   Then press the second disk home to the appropriate crankpin inside width 0.520"....and it's on     next step is to machine the second web bearing diameter in situ to fit the 25 mm bore ball bearing and to appropriate overall length.  I'll need to make a fixture to hold side A concentric while I turn side B.    Not that hard at all Mike.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on October 23, 2021, 06:27:48 PM
Nice!
 :popcorn: :popcorn: :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on October 23, 2021, 06:32:02 PM
Must feel good to get your process verified by the first good part!   :popcorn: :popcorn:

Dave, how are you guaranteeing the 0.520" spacing?  Do you have a gauge block or something that you're using to set between them as you do the press-fit?

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on October 23, 2021, 06:51:52 PM
Great to see the progress.  Sometimes the 'hard' stuff isn't as hard when you get into it.  Looks great Dave.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 23, 2021, 06:53:16 PM
Must feel good to get your process verified by the first good part!   :popcorn: :popcorn:

Dave, how are you guaranteeing the 0.520" spacing?  Do you have a gauge block or something that you're using to set between them as you do the press-fit?

Kim

I bumped it in with the mill vise, but I'm going to use an adjustable parallel that I can collapse and then reset.   I have .005" on both sides of each con rod bearing so I have some room for error, but I'm striving for on the nose.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 23, 2021, 07:06:17 PM
Great to see the progress.  Sometimes the 'hard' stuff isn't as hard when you get into it.  Looks great Dave.

YUP!!!   So now I'm wondering about the stuff I think is going to be easy!!!

Now coming this far, I'd say that .002" interference on a hardened pin in the 6-8 mm diameter range is no problem at all.   It hold very well!   With it pressed in 1/4 the way, it needed to be moved with a soft faced hammer, so pressed home it's not moving.   My engagement is 1 pin diameter deep. 

I used a 0.265" diameter crank pin as I can get graded reamers going up or down easily in the states.   Now over seas, 7 mm diameter may be a better choice, but check for reamers that are appropriately undersized ( 0.039 to 0.050 undersize) so that you get the press you need.    The pins were made from precision ground A2 tool steel, that aside from drilling through and parting to length, were finished diameter and +/- 8 microns..    It needed little other than hardening and polishing.   Lightly round and polish the ends with some 600 grit to ease the pin into the hole to start with.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: 90LX_Notch on October 23, 2021, 07:34:22 PM
Nice Dave!

-Bob
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on October 23, 2021, 08:07:09 PM
Great to see the first parts come together  :cheers:

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 24, 2021, 12:05:07 AM
I was able to get 3 more assemblies together and some photo's    I make myself a "Sledge" as at .06 insertion depth....you need it!

And a family shot.....lots of parts....

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on October 24, 2021, 05:36:09 AM
Great set of process pics, Dave.  Really helps me see how you're tackling this!

Nice box'o parts too!  :ThumbsUp:

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on October 24, 2021, 12:22:27 PM
Good stuff Dave!

Will there be a grub screw or some kind of pin to keep the disk from rotating on the pin?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 24, 2021, 01:17:29 PM
Good stuff Dave!

Will there be a grub screw or some kind of pin to keep the disk from rotating on the pin?

No   not required.    Once it's in the block it can't physically move.   

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on October 24, 2021, 01:21:16 PM
I was able to get 3 more assemblies together and some photo's    I make myself a "Sledge" as at .06 insertion depth....you need it!

And a family shot.....lots of parts....

The crankshaft looks to be coming together nicely.  :ThumbsUp: :ThumbsUp:

That was a neat trick to use the mill vice to press the pins home. A mill vice will keep everything square and parallel and you should be able to apply the force with much more control than with a fly press. I also like the depth stop ideas to set the length and gaps. What I could not see was how you aligned the two discs before you pressed the second disc home.

Cheers

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 24, 2021, 02:33:35 PM
I was able to get 3 more assemblies together and some photo's    I make myself a "Sledge" as at .06 insertion depth....you need it!

And a family shot.....lots of parts....

The crankshaft looks to be coming together nicely.  :ThumbsUp: :ThumbsUp:

That was a neat trick to use the mill vice to press the pins home. A mill vice will keep everything square and parallel and you should be able to apply the force with much more control than with a fly press. I also like the depth stop ideas to set the length and gaps. What I could not see was how you aligned the two discs before you pressed the second disc home.

Cheers

Mike

Hi Mike,

After you press the first side home, line up the second side by eye, and using the vise, press the pin about .06" deep using the vise.    Then I set the "A" side down on the flat tail of the vise, and brought a square up against it.    In this case, it was the sharp edge of a precision ground V block which is known square.   

If the two crank cheeks are aligned correctly, then both crank cheeks should touch the square at at all positions checked around the crank module assembly.    If it is not, I bring the assembly over  to my vise, and "bump" the "B" side web around rotationally around the partially installed crank pin until is passes this test.   It typically takes 3 or 4 or even more tries to get it acceptably aligned.

It doesn't need to be perfect, as the "B" side will be machined next using the finished "A" side as datum.   

Once acceptably aligned, I return the assembly to the vise, install the pre-set width stop, and press the "B" side home.   Once there ....it's not moving.

The "B" side has 0.04" on diameter, and .03" on length  to come off to get to finish dimension.   Any error left from the press fit assembly operation is removed by machining.

Dave


Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on October 24, 2021, 02:52:33 PM
Hi Dave,

Thanks. I can see how that works. Neat and simple, I had anticipated something more complex

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 24, 2021, 03:01:55 PM
Hi Dave,

Thanks. I can see how that works. Neat and simple, I had anticipated something more complex

Mike

Thanks Mike.....

Honestly....It's the way to go.   It gives you a chance to correct errors along the way and different steps of the process.   So far I am very happy with the Schilling approach, and can recommend it.   Schilling recommends .001" press fit....but I found with a hollow crank pin, you can go up to .002" which gives you some leeway on the pins and bored hole tolerances.   And I mean it....once that pin is in....It's not moving...I estimate it would take a 2 pound ball peen hammer to move a crank web once it's pressed home.....it's very secure....

Pins are .265 OD x .156 ID A2 hardened tool steel with 1144 SP crank webs with a .0015 - .002" press fit.

Crank pin is hardened to 50-55 Rc.

Build a few extras to make up a trial assembly to sort out doing this in YOUR shop..  You will learn alot.

Dave



Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on October 24, 2021, 03:14:35 PM

.........Build a few extras to make up a trial assembly to sort out doing this in YOUR shop..  You will learn alot.

Dave

Thanks Dave,

It is all too easy to overthink the problem. It's only when you have some hardware to play with, that you understand

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 24, 2021, 03:27:04 PM

.........Build a few extras to make up a trial assembly to sort out doing this in YOUR shop..  You will learn alot.

Dave

Thanks Dave,

It is all to easy to overthink the problem. It's only when you have some hardware to play with, that you understand

Mike

Aint that the truth!!!!

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 24, 2021, 10:49:43 PM
Making the lathe fixture to finish the crank cheek.....material was left on the bearing OD and face for this operation.   Needs some tapped holes.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 31, 2021, 09:42:39 PM
Much to do this weekend, including some quality time with my son.   Tonight I spent some time roughing out the crankshaft gear blank although it appears the belt on my lathe needs to be replaced...    :hammerbash:

The engine e on the Porsche 917 took its power from the center of the crankshaft.   My model will be the same.  and as this will be a 8 bearing ball bearing crankshaft, run out is critical, so I also spent some time checking the collets for my lathe and my dividing head for minimum runout.    I've gotten it down to .0005" on the dividing head and about .0003" on the lathe.....I'll be using a 1/2" collet   (3C in the lathe and #7 BS in the dividing head) so the blank has a 1/2" shank.

I'll use that for the "A" side of the gear (24 mm bearing diameter) and the gear teeth them selves,  then I'll part it and finish the opposite side in "The Fixture"!

Now "The Fixture" is a simple piece of stock with a 24mm socket that all the crank assemblies, the end crank shafts, and the center gear will be mounted to, to finish the "B" side bearing diameter concentric to the "A" side bearing diameter.    It's a simple part, and it's machined in situ.   Once its ready for use it CAN NOT come out of the lathe until all the parts are finished...so all the crank pieces need to be done first.

It appears I've worn out the serpentine belt on Samantha Bell    It has been nearly 10 years......

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on October 31, 2021, 10:23:03 PM
Funny - it looks like the crankshaft itself, is a lot stronger than the "Torsion Bar" they used for the Power Output Shaft .... but that might even be done on purpose  :thinking:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 31, 2021, 10:37:47 PM
I wouldn't be suprised admiral.     In the can am version of 1800 HP,  the output shaft was 25mm diameter and of titanium.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on October 31, 2021, 11:03:24 PM
Winding up the output shaft is much better than winding up the crank and messing up engine timing ect
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Don1966 on November 01, 2021, 04:29:03 AM
Looks great Dave!…… :Love:



 :cheers:
Don
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on November 01, 2021, 01:30:14 PM
Very nice Dave. :popcorn:

I noticed the crankshaft is symetric about the center with the exception of the two outside throws.  In sure there is a reason but it currently escapes me.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 01, 2021, 02:24:38 PM
Outside throws are symmetric   throws are all at 120 degrees

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on November 01, 2021, 02:34:55 PM
Outside throws are symmetric   throws are all at 120 degrees

Dave
In the CAD drawing picture, the throws from the middle to the right appear to spiral 120 degrees in one direction, but on the left they go one direction then back to match the center one? Why is that one on the far left the same as the center throws?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 01, 2021, 02:49:08 PM
The CAD image is wrong...
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on November 05, 2021, 07:56:42 PM
There's a lot of interesting stuff going on here  :praise2:  :praise2:  :wine1:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 05, 2021, 11:22:42 PM
Yes there is Roger!   too many hours at work ....but I hope to get some shop time in this weekend

I fixed the assembly model of the crank

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on November 05, 2021, 11:30:16 PM
Impressive design - amazing to make at model scale!

 :popcorn: :popcorn: :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 06, 2021, 11:49:53 PM
Impressive design - amazing to make at model scale!

 :popcorn: :popcorn: :popcorn:

Thanks Chris!    I have made a set of gear blanks that include the crank gear, the output shaft gear and the distributor/fan drive gear.   They are all 32 tooth 32DP gears, so just as well to cut them all in the same set up.
 
I made a TTS cutter holder for the gear cutter, and tomorrow I'll set up and cut them!   
today I spent some time doing fall clean up and organization.  I moved the old lathe bench out of the shop, and put my table saw in the basement for the winter.   Took the A/C out of the window and turned on the heat!   It was 24 F outside this morning!!!


Oh and I fixed the SB.   I tried tightening the belt, and that fixed it for now........I suspect I'll need to change that belt before too long

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 07, 2021, 07:07:09 PM
Im set up....has anybody climb milled with a gear cutter before?   

Don't mind saying this is spooking me ....I've cut a lot of gears conventionally....never climb....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on November 07, 2021, 07:24:10 PM
Allways climb mill gears
Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 07, 2021, 07:29:45 PM
Thanks Mike!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on November 07, 2021, 07:34:35 PM
One fulĺ depth pass then a spring pass.
Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 07, 2021, 07:36:09 PM
One fulĺ depth pass then a spring pass.
Mike


That's the plan
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 07, 2021, 07:37:23 PM
Gonna put a footstock on it though

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on November 07, 2021, 09:15:04 PM
Gonna put a footstock on it though

Tailstock???
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: kuhncw on November 07, 2021, 10:30:15 PM
Allways climb mill gears
Mike

Mike, what is the reason for climb milling gears vs conventional milling?

Chuck
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 08, 2021, 12:11:45 AM
Gonna put a footstock on it though

Tailstock???

Cylindrical Grinders AND Dividing heads it's called a footstock

On a lathe it's a tailstock

I didn't name them.......

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 08, 2021, 12:25:58 AM
OK    good evening  it'

I was able to cut the teeth....not without incident, but I guess I'm not surprised as it's the first time cutting gears on a CNC mill.

I've cut many gears on manual mills , like my #12 Van Norman mill....and it was ALWAYs  conventional cut always towards the dividing head.   That is not an option with my software on a CNC mill as far as I can tell.   But no matter it climb cut quite nicely.   CNC is always better as climb milling.....it's just not my experience ....so I got nervous....but there was no need.

300 rpm was just fine, and I think with the mist coolant that I could safely go to 400 without any problems
What I did wrong, was set the center of the cutter on center with the work piece quite precisely....which is what I would do with my Van Norman or my F1....there was the rub!    Zero on the program is the bottom edge of the cutter, not the center...so it cut low by half a cutter thickness....  Once I got that sorted out I started making decent teeth!   but of course the damage was done.

The mill doesn't have the snot to run at 3 inch/min at that speed....2 in/min is just fine.    I'm not surprised as the spindle will run happily at 10,000 rpm so as a belt drive machine, Im not at all surprised.    I can work with it, as the gears are small, and I don't suspect I'll need to cut anything of bigger DP than Mod 1 or 32 DP.

So I'll make up another blank and have at it....this week I think....we'll see what work brings to my desk...

I have a BS1 dividing head....I think a BS0 might be better given the table size....  I'll look into that

Thanks for following along......

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: john mills on November 08, 2021, 12:52:09 AM
climb milling is always better than conventional milling  but only on machines rigid enough and no backlash preloaded ball screws and the work must be held  to control the cut .  at apprentice school they had a good big heavy horizontal mill with back lash eliminator but
when they tried to show how it worked it picked up the vice and threw it over the end of the table it was a good big solid vice firmly held with 5/8" bolts so they put it all back making sure it was done up tight and tried again same thing so they didn't try again.whith good cnc machines with preloaded ball screws  and good spindles i always climbed mill unless the set up was likely to be a bit springy .
good you have the gear cutting working.
  john
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 08, 2021, 01:02:17 AM
YUP   35 years turning cranks and now slinging pixels!.......designed quite a few of them too....just never got a chance to run CNC myself till I got my mill....it's a bit of a learning curve...and you have to learn to trust the machine and change your work methods....

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 08, 2021, 01:19:53 AM
Case in point

https://www.modelenginemaker.com/index.php/topic,649.msg6073.html#msg6073

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: john mills on November 08, 2021, 08:09:04 AM
your little mill with high spindle speeds carbide end mills should love climb milling  when you start with larger end mills in cnc machines
plowing into tool steels is something to think about but it works and you quickly see it works i started more than 40 years ago but
i had to wonder on old machines that have long seen there best but never had any trouble i didn't climb mill holding tough steels in a indexing head and using larger cutters where the setup needs to be rigid .
John 
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on November 08, 2021, 06:04:18 PM
YUP   35 years turning cranks and now slinging pixels!.......designed quite a few of them too....just never got a chance to run CNC myself till I got my mill....it's a bit of a learning curve...and you have to learn to trust the machine and change your work methods....

When you convert to the CNC way: you must trust your machine and trust the drawings.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 09, 2021, 12:57:41 AM
YUP   35 years turning cranks and now slinging pixels!.......designed quite a few of them too....just never got a chance to run CNC myself till I got my mill....it's a bit of a learning curve...and you have to learn to trust the machine and change your work methods....

When you convert to the CNC way: you must trust your machine and trust the drawings.

Mike
t
Yes you do!   I set the center of the cutter at the center of the gear.....of course the software set zero at the bottom face of the cutter set to cut the bottom face of the gear tooth slot.....so half a gear cutter thickness low....once I convinced myself that I set it on center....like 4 times....it dawned on marble head that the software wasn't reading my mind...    I say I sack the software!!!!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on November 09, 2021, 01:12:58 PM

I set the center of the cutter at the center of the gear.....of course the software set zero at the bottom face of the cutter set to cut the bottom face of the gear tooth slot.....so half a gear cutter thickness low....once I convinced myself that I set it on center....like 4 times....it dawned on marble head that the software wasn't reading my mind...    I say I sack the software!!!!

Dave

There is still a lot of merit in using less sophisticated CAM software than Fusion 360 and the like.  :killcomputer: 

OK, you may have to do more of the work, but the lower level of automation leaves you, rather than the software, in command of the process.


   I say I sack the software!!!!

Dave

Yep, I go along with that as you must also trust your software or have software you can trust

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 15, 2021, 01:25:08 AM
Good progress today!   First of three gears went great.   I'll cut some more this week .   I need 3 of this tooth count.

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on November 15, 2021, 01:56:18 AM
Looking great!  What is the black coating in the gear teeth?


 :popcorn: :popcorn: :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 15, 2021, 02:13:26 AM
Just a shadow.no coating

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on November 15, 2021, 05:29:57 AM
Nice looking gear!  Is it going to stay this wide? Or get narrower before actual use?

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 15, 2021, 11:13:05 AM
Nice looking gear!  Is it going to stay this wide? Or get narrower before actual use?

Kim

Hi Kim.   Thanks for looking in!    No actually it will finish off looking like the picture below.   To physically cut the part, the blank needs to be 1" away from the face of the DH spindle...so at the moment it's a gear on a stick...
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on November 15, 2021, 12:37:16 PM
Good progress today!   First of three gears went great.   I'll cut some more this week .   I need 3 of this tooth count.

Dave

Another small step foreward

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 15, 2021, 12:51:07 PM
Good progress today!   First of three gears went great.   I'll cut some more this week .   I need 3 of this tooth count.

Dave

Another small step foreward

Mike

YUP   And with what's going on in my life.   well small steps is all I can do.  i'll endeavor to take them every week.

Dave

 
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on November 15, 2021, 09:53:08 PM
Great to see progress Dave and a nice result  :ThumbsUp:

I would have said that only one of them ends up as a part of the crankshaft  :headscratch:

Are the two others idlers or for the Oil Pumps ?

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 15, 2021, 10:09:26 PM
Per


Power comes from the center of the crank
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on November 15, 2021, 10:14:55 PM
So this time my memory wasn't half bad  ;D  thank you Dave.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 15, 2021, 10:19:01 PM
So this time my memory wasn't half bad  ;D  thank you Dave.


 :headscratch:

No the output shaft is below the crank shaft...so that's the primary, and the output way shafts

The other gear is for the fan and the distributors.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on November 15, 2021, 10:34:31 PM
Very interesting arrangement on the output shaft!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on November 16, 2021, 11:54:40 AM
OK, I wasn't clear.

I understand it as, two of the gears you made, are for the Crank and the Output shaft (the red line) - they certainly appear to be same size ...?

I admit that I guess that the third will be slimmed down and placed on the last shaft in the picture .... so, all three mess with each other .... I know it's a dangerous assumption ....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Hugh Currin on November 16, 2021, 02:44:25 PM
Dave:

Great progress. Thanks for dragging us along.

For the "gear on a stick", did you consider making a "pinion shaft"? What I mean is cutting the gear section long enough to get all three gears from. More overhang but only cutting one long gear. Just curious.

The center take off on the crank makes sense to me. The torque is half on each side rather than pulling power from one end. The crank will see more cyclic loading than the final output shaft after the gear. Might explain why the final output isn't larger than the crank? Makes sense for a racing motor, but would probably be more expensive for production vehicles.

Thanks again.

No actually it will finish off looking like the picture below.   To physically cut the part, the blank needs to be 1" away from the face of the DH spindle...so at the moment it's a gear on a stick...
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 17, 2021, 01:12:38 AM
Hi Hugh,

The problem I have is that with the dividing head on my table, I lose some travel...to complicate it, I need to have the HS side of the gear at least 1" away from the spindle of the dividing head.   I run out of room to put the footstock/tailstock on the table...so I can't make the gear blank too long....so you end up with a gear on a stick ......Im going to build a sub table that lets me hang the HS way to the left over the table drive, that will let me get a footstock/tailstock on

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Hugh Currin on November 17, 2021, 04:43:56 AM
Dave:

Well, that answers that question. Does sound like you considered it though.

Nice progress.

Thanks.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Mike R on November 18, 2021, 03:20:21 AM
Dave,
Looks like good progress.  Are you creating specific code for each gear in Fusion (sorry if I missed it, skimmed through and if I read it I didn't register it).  I wrote a simple bit of G-code to conventional mill gears - edit the code with the # of teeth, gear width,  cutter diameter, cut depth, etc. and it does the rest.  Seeing Mikes comment on climb milling I may have to revisit and redo the code to climb mill.  regardless let me know if you want me to share it.  I wrote a DP version and a Module version and they seem to have worked out so far for me.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 18, 2021, 11:27:12 AM
Thanks Mike!    Unfortunately I don't currently have an A axis on my mill other than my old school dividing head....
I have a simple program that cuts a tooth full depth with a gear cutter and follows up with a "Dead pass"...and that completes the cycle
Index the head and hit cycle start...simple as that

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 21, 2021, 03:19:31 PM
No machining this week....had a spot of bother design wise that I missed, but I've got the solution well in hand....and I'll expound when It's sorted out.

Luckily I found it before I got into it!..

It's a risk you take on a new design....... :old:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on November 23, 2021, 08:23:47 PM
It's a risk you take on a new design....... :old:
Been there got the teeshirt and the cap  :toilet_claw:  ::)
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on November 26, 2021, 05:41:28 PM
Can't recall one engine I designed where the design didn't change somewhat as the build progressed, either through errors in the design I uncovered along the way or just a better design discovered as I 'got there'.  To me, it's just part if the design/build process.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on November 26, 2021, 06:08:04 PM
Can't recall one engine I designed where the design didn't change somewhat as the build progressed, either through errors in the design I uncovered along the way or just a better design discovered as I 'got there'.  To me, it's just part if the design/build process.

Spot on Craig. I look upon the combined design/ build process is a creation process.

Dave will soon have it fixed and the engine design will be stronger than ever.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on November 26, 2021, 10:28:20 PM
Can't recall one engine I designed where the design didn't change somewhat as the build progressed, either through errors in the design I uncovered along the way or just a better design discovered as I 'got there'.  To me, it's just part if the design/build process.

Spot on Craig. I look upon the combined design/ build process is a creation process.

Dave will soon have it fixed and the engine design will be stronger than ever.

Mike

Yes it will!!!     I have to do "Work" work this week....including yesterday and today...but I'll roll back in shortly.   
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: JonC on December 02, 2021, 12:31:30 PM
Great work Dave.

Following along quietly in the background, learning all the way.

Jon
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 04, 2021, 04:47:50 PM
So I had a situation.     :toilet_claw:

I found that the 4mm bolts holding the crank together where going to break out into the root of the center gear on the  crank.    That WAS a 32 tooth 32 dp gear, to fix that, I changed the gear to a 35 tooth.   Doing  that increases the distance between the upper distributor/fan shaft and to the output shaft.   That changes the engine block ....and the gear centers to the cams.....lots of bad words were used......

I just didn't see it, as it was approximately flush....why didn't I see it?   well I modelled the holes in the crank at .386" from the center.....and had a senior moment when I modeled the gear and typed in .368.....a simple transposition.....but it was enough to not see it

OK...the good news.   I have not started machining the block!....so I took a divergence, and remodeled the block to correct this

Gear counts were  32/56  35/40    for a 2/1 reduction

NOW   

Gear count is 35/56  32/40   also for a 2/1 reduction

It required changing the centers of the gears in the gear towers, and a change in the block centerlines, but nothing else that I can see.   It also afforded me the ability to put in bigger bearings on the lay shafts.  So it worked out for the best going forward

Then I had to work for the last 14 days straight including the holiday......so nothing has happened so far machining wise.

I was able to get a start on the new block, and sort out the placement of the internals.    so we're almost back on track.

the "honey do" list is strong today, but I might be able to get back out there and start cutting 35 tooth gears tomorrow....stay tuned....

I'm also glad I started the engine from the center out, or I'd of scrapped the block.   So far I've only scrapped a gear.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on December 04, 2021, 05:58:58 PM
Sorry to hear about the problem, but it sounds like you've got it sorted, Dave.

Looking forward to seeing your progress after you get the family taken care of (most important, of course!)

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on December 04, 2021, 06:25:26 PM
At least it was found before the block was all made!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on December 04, 2021, 07:51:53 PM
Hello Dave,

Sounds like the 'fix' was not too drastic. Lucky you discovered the problem when you did, before you started on the crancase itself. Hopefully it will be plain sailing from here on.

Take it easier

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 04, 2021, 08:44:44 PM
Hello Dave,

Sounds like the 'fix' was not too drastic. Lucky you discovered the problem when you did, before you started on the crancase itself. Hopefully it will be plain sailing from here on.

Take it easier

Mike

Amen to that!!!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on December 04, 2021, 10:14:56 PM
Quote
well I modelled the holes in the crank at .386" from the center.....and had a senior moment when I modeled the gear and typed in .368.....a simple transposition.....but it was enough to not see it

I guess that most of us have seen the 'crooked sentences' where some of the letters has been rearranged ....
Almost everyone that sees them can still read them and I guess that something similar is going on here + you will recognize all the digits that was part of your original plan -> I'm not sure Senior is to blame, but that it could have happened to everybody ....

Still good that you caught it so early in the build  :ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 04, 2021, 10:47:39 PM
Yeah I'd say I was pretty damn lucky I started with the crank.......

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on December 05, 2021, 07:40:44 AM
That was a good save  :ThumbsUp:  :ThumbsUp:  :wine1:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 19, 2021, 04:58:46 PM
OK  between work and this, I'm just about all caught back up from the "issue"...
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on December 19, 2021, 05:00:46 PM
Wow, thats a lot of parts!
 :popcorn: :popcorn: :popcorn:
Chris
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on December 19, 2021, 05:08:16 PM
Wow!  That's an amazing amount of CAD work, Dave!  Very impressive engine.

Hope you get some time over the holidays to make more progress!

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on December 19, 2021, 05:23:46 PM
Hello Dave,

The CAD model looks great. I like the look of those external oil pumps. Hope you get some shed time soon.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 24, 2021, 01:03:33 AM
Oh we're getting closer

I'm off until the 4th.   Can't wait!!!

I've not had a vacation for over 2 years.....

Shop time!!!!
Block is coming along nicely

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on December 24, 2021, 01:12:49 AM
No vacation in two years :o wow!  Sounds like you’re long overdue.  Have fun in the shop but remember, the family would like to see you every Once in a while. :LittleDevil:

Hope your shop time is productive  :cheers:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 31, 2021, 03:08:00 AM
My vacation has been going well!    Stuff is getting done, tomorrow I focus a bit more on the engine.   I have the gear cutter I needed (32 DP #3 cutter) and I have a fixture ready to make to hold the crank webs for final turning.   I'm hoping for a good time in the shop tomorrow.   

I got a phone call from my boss today.....oh boy!.......it was good news though.....A little reward for my hard work .....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Don1966 on December 31, 2021, 03:36:05 AM
Great news bud glad to see you getting shop time in. But hey man how about pics…….. :stickpoke:


 :cheers:
Don
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 31, 2021, 03:51:17 AM
Great news bud glad to see you getting shop time in. But hey man how about pics…….. :stickpoke:


 :cheers:
Don
What's for breakfast!...
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on December 31, 2021, 03:56:22 AM
I'll need to make a bushing for the gear cutter...it's 1" bore, and my arbor is currently 7/8"

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on December 31, 2021, 06:16:08 AM
I'll need to make a bushing for the gear cutter...it's 1" bore, and my arbor is currently 7/8"

Dave

Doesn’t it always happen, I have a drawer full of them!  You’d think one might fit. :shrug:

Really enjoying this build Dave.  Always looking for the next installment.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 01, 2022, 11:53:16 PM
Productive day in the shop today!     I'll post some photo's and a vid a bit later, but I got the 3 main drive gears cut.   They'll need the bearing diameters finished, but i'll do that tomorrow when I start the final machining of the crankshaft.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 02, 2022, 12:39:49 AM
Just gears today.   Tomorrow, I start on the final machining of the crankshaft components

erulLZQaJzI
The lathe needs a very good cleaning though first.....I could say the same about the mill!!!...

Dave


Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on January 02, 2022, 05:55:17 AM
Great to see you had some shop time, Dave!

That's nice looking gear, for sure!  :ThumbsUp: :popcorn:
Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on January 02, 2022, 10:38:25 AM
Holliday and shoptime  - things are improving for you or ....
Anyway nice to see that you are moving forward on this build again.

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 02, 2022, 10:59:36 AM
Great to see you had some shop time, Dave!

That's nice looking gear, for sure!  :ThumbsUp: :popcorn:
Kim

3 gears!     :whoohoo:
I'm looking forward to finishing the crank!   I needed the center gear before I could do the final operations to the crank.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Don1966 on January 02, 2022, 10:03:11 PM
Nice gears Dave….. :ThumbsUp:


 :cheers:
Don
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 02, 2022, 11:35:52 PM
Great progress on the crankshaft segments.  The final operation for each segment is to turn and face the unfinished end while mounted by the finished end in a "insitu" fixture in the lathe.   I've gotten to #3 of 6 segments, and I'm calling it for tonight... One wrong move now and the parts are junk...so come back and finish it when I'm fresh.......Here's some photo;s including 2 segments bolted together!...

1   turning fixture. It stays in the lathe until all the sections are done

2   The semi finished segment mounted in the fixture

3    The bearing diameter turned and the bearing fitted

4    Two finished segments with a bearing mounted in place in the center
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on January 02, 2022, 11:59:16 PM
Slick setup! And knowing when to walk away and rest/reset is a key workshop skill.


 :ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 03, 2022, 12:05:51 AM
Slick setup! And knowing when to walk away and rest/reset is a key workshop skill.


 :ThumbsUp:

Keeping it all clean is really tough.....it doesn't take anything to make it all run out...

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on January 03, 2022, 11:22:02 AM
Splendid  :ThumbsUp:  :ThumbsUp:  :wine1: Good to finally get some workshop time  :)
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 03, 2022, 09:25:08 PM
Crank is done!!!    this will be the hardest part to make, so i feel pretty good about the rest of the model!    Hardened crank pins, 8 ball bearing main bearings, and the center power take off gear just like the prototype.   The crank, a CAD model of it, and a picture the real thing with the crank case split

Interestingly enough, the best way to get the small chips off the parts while I was machining was a clean toothbrush!!.. 

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on January 03, 2022, 09:31:49 PM
Looks good Dave.   :ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on January 03, 2022, 09:40:20 PM
Very impressive!!


In the picture of the real engine, the gear teeth extend above the crank sides. Did you change the gearing on your design, or is that gear not there yet?  :thinking:


 :popcorn: :popcorn: :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 03, 2022, 09:46:40 PM
Very impressive!!


In the picture of the real engine, the gear teeth extend above the crank sides. Did you change the gearing on your design, or is that gear not there yet?  :thinking:


 :popcorn: :popcorn: :popcorn:

The real engine is plain bearing, I'm using 25 x 32 x 4mm ball bearings.   Those are the parts sitting above the crank gear
The crank is composed of 6 crank sections and a center gear.   Here's a model of a crank section
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on January 03, 2022, 09:48:38 PM
Very impressive!!


In the picture of the real engine, the gear teeth extend above the crank sides. Did you change the gearing on your design, or is that gear not there yet?  :thinking:


 :popcorn: :popcorn: :popcorn:

The real engine is plain bearing, I'm using 25 x 32 x 4mm ball bearings.   Those are the parts sitting above the crank gear
Gotcha!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on January 03, 2022, 10:12:48 PM
Hello Dave,

The crankshaft came together quickly towards the end, and before the end of your holiday break. Well done, it looks fantastic.

Did you measure the run-out before each section was added? If not, you can always mount and clamp two adjacent bearings to Vee blocks and check the runout of the each section.  The whole cranksfaft looks long and flexible, so the eight equi-spaced bearings should have little difficulty in pulling out a few thou of run-out, That is, if there is any.

Fantastic work

Mike   :praise2: :praise2: :praise2:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 03, 2022, 10:24:43 PM
Hello Dave,

The crankshaft came together quickly towards the end, and before the end of your holiday break. Well done, it looks fantastic.

Did you measure the run-out before each section was added? If not, you can always mount and clamp two adjacent bearings to Vee blocks and check the runout of the each section.  The whole cranksfaft looks long and flexible, so the eight equi-spaced bearings should have little difficulty in pulling out a few thou of run-out, That is, if there is any.

Fantastic work

Mike   :praise2: :praise2: :praise2:

I checked the fixture before and after each section was turned and it was consistently in the .0002-.0004" radially and axial run out range.  That said, I don't think I could do any better if I tried.     I've not measured it yet, but I will, but I think it'll be fine.   The fixture worked very well, and asl long as you were gentle, it stayed put.   A somewhat common occurance was to slightly marr the face surface, so I would take a thou off, just to clean it up after each couple of sections.     To drive the thickness, I made up a gage block stack, and set the axial distance from the face of the fixture to the tool, and then set the bed dial indicator to zero, so I knew where to go as I turn/faced the crank cheek for the bearing.    Just keep and eye on the fixture, and keep checking it with a dial indicator to make sure it stays true.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on January 03, 2022, 10:54:17 PM

I checked the fixture before and after each section was turned and it was consistently in the .0002-.0004" radially and axial run out range.  That said, I don't think I could do any better if I tried.     I've not measured it yet, but I will, but I think it'll be fine.   The fixture worked very well, and asl long as you were gentle, it stayed put.   

.  .  .  .  .  .

  Just keep and eye on the fixture, and keep checking it with a dial indicator to make sure it stays true.

Dave

If you keep checking the fixture and it stays put and always indicates true; then there is not much else you can do. The crankshaft will be as true as you can make it.

Did I say it looks fantastic.

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 03, 2022, 11:08:04 PM

I checked the fixture before and after each section was turned and it was consistently in the .0002-.0004" radially and axial run out range.  That said, I don't think I could do any better if I tried.     I've not measured it yet, but I will, but I think it'll be fine.   The fixture worked very well, and asl long as you were gentle, it stayed put.   

.  .  .  .  .  .

  Just keep and eye on the fixture, and keep checking it with a dial indicator to make sure it stays true.

Dave

If you keep checking the fixture and it stays put and always indicates true; then there is not much else you can do. The crankshaft will be as true as you can make it.

Did I say it looks fantastic.

Mike

Thanks Mike!!!    I'm excited!     Rods and bearings next!

I'm going to pick up the gears for the distributors /fan this week, so I can finalize the rest of the gears.    Lots more gear cutting in my future!!!...

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on January 03, 2022, 11:15:23 PM
Woa - now this is a major point in this build that you just completed and it looks fantastic  :praise2:

Looking forward to the rest as you find time  :cheers:     :popcorn:

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 03, 2022, 11:19:17 PM
Woa - now this is a major point in this build that you just completed and it looks fantastic  :praise2:

Looking forward to the rest as you find time  :cheers:     :popcorn:

Per
Definitely the hardest part of this build I think    I think if I can build this, I can build the rest.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on January 04, 2022, 12:42:04 AM
Congratulations on getting the crankshaft done successfully, Dave! It looks great! :ThumbsUp: :cheers:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Hugh Currin on January 04, 2022, 03:24:43 PM
Dave:

Very nice results. It almost looks like 6 cranks in bearings connected together, as in each is solid by itself only needing to transmit torque on down the line. Very unique and allows roller bearings. I'm surprised the original used bushings.

How do you keep the toothbrush clean??

Again, great results. Thanks.

Crank is done!!!

Interestingly enough, the best way to get the small chips off the parts while I was machining was a clean toothbrush!!..
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 04, 2022, 04:42:25 PM


How do you keep the toothbrush clean??




Ya know Hugh,   I have no idea.   I have not noodled why the brush works and nothing else would, there doesn't appear to be anything on the brush....I suspect electrostatic effects....but all I know is it worked amazingly well!!!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 05, 2022, 08:55:08 PM
Bevel gears for the fan drive on order....they  dont give those away at Mcmaster carr!....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on January 06, 2022, 03:30:56 PM
Dave, why not cut your own bevel gears? Not that much harder than the straight ones you cut.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 06, 2022, 10:40:54 PM
Other things to machine....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 09, 2022, 03:06:22 AM
In the interest of getting accurate shaft centerlines, I'm working on the fan shaft gears and the output shaft gear trains, so I can measure that up and work it into the block dimensions.  I got the bevel gears so I'm working that out now.   Hopefully I'll have some pictures to show tomorrow....



Work is about to get nuts....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on January 10, 2022, 12:45:51 AM
I hear you steamer. I'm finally making good progress on the radials and I'm hearing 7 days 12 hours at the end of February. Just plug along when you get time and the crazy will end someday.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 10, 2022, 01:12:03 AM
I hear you steamer. I'm finally making good progress on the radials and I'm hearing 7 days 12 hours at the end of February. Just plug along when you get time and the crazy will end someday.

Thanks buddy....The struggle is real!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: ozzie46 on January 10, 2022, 12:39:38 PM
I hear you steamer. I'm finally making good progress on the radials and I'm hearing 7 days 12 hours at the end of February. Just plug along when you get time and the crazy will end someday.

UH Wait Radials What radials?

Ron
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 10, 2022, 10:12:21 PM
I hear you steamer. I'm finally making good progress on the radials and I'm hearing 7 days 12 hours at the end of February. Just plug along when you get time and the crazy will end someday.

UH Wait Radials What radials?

Ron

 8) I know something you dont........ :lolb:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: ozzie46 on January 10, 2022, 10:55:46 PM
Oh great!! Now the suspense will keep me awake for quite awhile! :hammerbash: :hammerbash: :hammerbash:
Ron
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on January 10, 2022, 11:05:03 PM
I meant readables, books. Damn spell check.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: ozzie46 on January 11, 2022, 11:39:32 AM
Yeah. Right, and moon is made of green cheese.  ::) ::) ::)

Ron
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on January 11, 2022, 10:32:05 PM
Oh man I love cheese.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 11, 2022, 10:34:29 PM
Oh man I love cheese.


 8)
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 16, 2022, 02:05:01 AM
Just about finished with the initial drive gears....output shaft and fan drive.    The fan drive is press fit   ( .002") so I don't think it's going anywhere!

compared to the original....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on January 16, 2022, 09:38:23 AM
Òh! So sweet
Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on January 16, 2022, 10:40:44 AM
That's some nice work right there too bad you have to hide it in the engine.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on January 16, 2022, 10:41:50 AM
Great - so now you also have the centre distances  :ThumbsUp:

What do you plan to do next - the block, or ?

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 16, 2022, 10:56:32 AM
Great - so now you also have the centre distances  :ThumbsUp:

What do you plan to do next - the block, or ?

Per
Probably finish the connecting rods.    I should have the new block all sorted out by then     I'm still prognosticating over lubrication solutions....its getting close.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 16, 2022, 12:51:02 PM
That's some nice work right there too bad you have to hide it in the engine.

Steve...it is so nice to use a lathe that you can explicitly trust...I ask for it...it gives it!!!    .Turning the bearing diameters to size within .0005" was really easy once set up correctly.   Rinse and repeat!

As a side note, I have the spindle bearing clearance adjusted to the SouthBend spec, for really tight work, it might want to be tightened up a bit...but it did well enough!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on January 16, 2022, 03:02:32 PM
That is work to make even Herr Mezger proud! Very impressive.   :ThumbsUp: :cheers:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 16, 2022, 05:08:12 PM
That is work to make even Herr Mezger proud! Very impressive.   :ThumbsUp: :cheers:

Thanks Ron....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 16, 2022, 06:20:08 PM
Final thrust bearing design for both the crank and the output shaft, though I plan on doing the fan layshaft in a similar manner, its not laid in yet

I came up with this while doing the new block.  Replace the crank bearings either side of the gear with flanged bearings of the same size, so drop in replacements.   so now the crank is captured at the center...which growth wise minimizes  the movement axially.   Additionally, I have needle roller bearings on the output shaft with bronze thrust washers either side.  The gear is pressed and woodruff keyed to the shaft which is a 8mm piece of Thompson shafting  ( case hardened and ground)   The flange of the crank bearing is let into the thrust washers such that the thrust washers can not rotate, and are radially supported on the ID by the stationary OD race of the needle bearings.   Easy to lubricate with some cross holes and as thrust loads are incidentals, it should be fine.   Drive to the oil pump will go to the left of the picture off the end of the output shaft....as is prototypical.   Some form of oldham coupling, but I'm entertaining moving the pump into the block but accessible from the left end.....stay tuned!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on January 17, 2022, 11:52:30 PM
That crankshaft is deeeeeeeeeelux Dave.   Just superb!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 18, 2022, 12:13:31 AM
That crankshaft is deeeeeeeeeelux Dave.   Just superb!

Thanks Craig,  its starting to fill in nice....

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Art K on January 18, 2022, 02:56:14 PM
Dave,
Things are looking very good!  Great that you can just swap out the center bearings and have thrust under control.
Art
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on January 22, 2022, 08:16:21 AM
Excellent  :praise2:  :praise2: That's a neat solution for the thrust bearings  :ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on January 31, 2022, 12:09:14 AM
OK so full design intent  installed.     Everything but the scavenge side on the right side block with strainers....But not tonight
The pump is iin  as is the drive for it, and the pressure feed passages to the spray bar above.  I also have the scavenge delivery passages in the left block

What remains is the fan drive items, which I'll get into, and the aforementioned scavenge ports and strainers  ect on the left block.

I'll build the output shaft and the oil/scavenge pump system next and debug on the bench.   Then the fan drive.   THEN  the blocks...that will give me a chance to develop everything that goes in the block before I cut metal on the block ...

Oil and scavenge pumps were sized by copying Ron Colonna's pump dimensions from his Offy, which is only slightly smaller than this engine, and had a pressure lubed/plain bearing main and rods...so this should be more than enough to feed this girl..

I have distributors designed and modeled, but before i finalize, I need to get my cross helical gears from across the pond....its on the list

Work has been crazy.....67 hours last week,,,,and they want more....I played hooky today.....

Dave

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on January 31, 2022, 11:33:05 AM
Hello Dave,

That's a neat little pump and installation with all the pressure and delivery passages machined into the blocks. I see you have gone away from the idea of an externally located pump. You said the external location was to give access to the pump during development. You are obviously more comfortable with this version of the design, because when the two sides of the crankcase are eventually bolted together, it's in there for keeps.

67 hours last week...... you can  :censored: that

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on January 31, 2022, 11:38:26 AM
Looks like a very neat and easy installation of the pumps  :ThumbsUp:

I must admit that I'm not sure I got all the detail right in my head. I presume that the two lower holes are the oil entry points for the two of tree pumps - but what is the the input to the one closest to the pumps input shaft ?

The recesses on the pumps outputs, are they for the o-rings  :thinking:

Great that you got a good income after some hard times, but I understand if you would have liked it, to be more even workload over time ....

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: JonC on January 31, 2022, 12:59:15 PM
Hi Dave,

Incredible build so far and love it every time there's a bit more progress to be admired. The thrust bearing idea is excellent, are you using 25x32x4 bearings? I'm using these on the DFV crank but cannot find a flanged version of it.

Thanks

Jon
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 01, 2022, 04:13:02 AM
Hello Dave,

That's a neat little pump and installation with all the pressure and delivery passages machined into the blocks. I see you have gone away from the idea of an externally located pump. You said the external location was to give access to the pump during development. You are obviously more comfortable with this version of the design, because when the two sides of the crankcase are eventually bolted together, it's in there for keeps.

67 hours last week...... you can  :censored: that

Mike

14 hour day today too.....but they gave me a nice raise.....

Mike, You sir are correct on all counts.....here's the scoop....no matter how I tried to do it, that external pump looked like Q(*E(*Q .    It is NOT how the 917 engine looks...  My previous comments about fiddly bits inside the engine is still accurate.    To get around that, instead of running the pump with a gear train at about 1/2 engine speed, I'll be running this one at engine speed.   Pump speed is well within limits for a gear pump ( pitch line velocity below 20 m/s.    In this application it's under 3 m/s at 8000 rpm)    But this pump needs to be reliable....so I'll be following a theme that has already saved my bacon on thius project....work from the inside out.     SO   to develop this pump and make it reliable, it will be the next thing on the list to build, followed by the power layshaft and the fan/distributor layshaft.    And I'm very happy I'm taking this path as it's like the REAL one......

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 01, 2022, 04:21:55 AM
Looks like a very neat and easy installation of the pumps  :ThumbsUp:

I must admit that I'm not sure I got all the detail right in my head. I presume that the two lower holes are the oil entry points for the two of tree pumps - but what is the the input to the one closest to the pumps input shaft ?

The recesses on the pumps outputs, are they for the o-rings  :thinking:

Great that you got a good income after some hard times, but I understand if you would have liked it, to be more even workload over time ....

Per
What you see there Per is 3 pumps stacked on top of each other.    From the left to right....the first is the pressure pump,   The second and third are scavenging pumps.  They each have 1.5 x the capacity of the pressure pump.     the round recesses on the side are for seals that seal the pump agianst each half of the engine block.   All passages are drilled passages leading to the top of the block and down a stand pipe with 7 nozzles.   1 for each crank bay and 1 for the gear bay in the middle.   The scavenge pumps will draw from the two bottom sump wells with strainers down low.   All that will be on the RIGHT side engine block half.   Not shown..    JUST like the real one.   there will be 1 hose into the right block feeding the pressure pump from the scavenge oil tank, and the two scavenge pumps down to a hose on the left side of the block up front.

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 01, 2022, 04:28:01 AM
Hi Dave,

Incredible build so far and love it every time there's a bit more progress to be admired. The thrust bearing idea is excellent, are you using 25x32x4 bearings? I'm using these on the DFV crank but cannot find a flanged version of it.

Thanks

Jon

Thanks Jon,   The McMaster Carr part number is in the top left of the corner of the picture below. 
https://www.mcmaster.com/4390N142/

Dave



Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: fumopuc on February 01, 2022, 07:11:11 AM
Hi Dave, I am following along quietly all time.
Impressive to watch the progress.
There is an always upcoming desire to ask you for the plans/drawings if it is coming closer to the final stage.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 01, 2022, 11:39:03 AM
Hi Dave, I am following along quietly all time.
Impressive to watch the progress.
There is an always upcoming desire to ask you for the plans/drawings if it is coming closer to the final stage.

That will be a ways off sir.   But I think it doable....not sure which decade... :lolb:at this rate

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 01, 2022, 11:46:21 AM
The other place to look for all kinds of small bearings is Fast Eddy's


https://www.fasteddybearings.com/

They provide specialty bearings to the RC industry.  Good stuff

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on February 01, 2022, 01:47:30 PM
67 hours is insane.  Many years ago, a group of us ‘hot shots’ started our own company.  We put in hours like that for around two years… but then we were working for ourselves so that is different.  We learned a valuable lesson on marketing; much better to have a crappy product and great marketing.  Unfortunately we were the opposite. After two years we realized we were getting nowhere and probably would continue to go no where.  It was time to move on.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 07, 2022, 12:33:31 AM
Made some progress today!!

Here are all the major parts for the pressure and 2 scavenge pumps for the engine.   First operation on all is complete.   I designed the pump so that all critical dimensions could go in with 1 set up and 1 tool...minimizing the errors as much as I can.   Now  they get chopped off the bar, and mounted, finished face down, on a fixture so the back side of each part is finish machined.    This will maximize the chance that the parts are parallel.   Next each part will get its oil ports put in, and then cleaned up and deburred.

Productive afternoon!

Maybe with CNC   I can keep up with Chris! :insane: :Doh:

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on February 07, 2022, 02:32:47 AM
Nice! The planning on those parts looks well worth it.   :popcorn: :popcorn: :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: JonC on February 07, 2022, 09:27:33 AM

[/quote]

Thanks Jon,   The McMaster Carr part number is in the top left of the corner of the picture below. 
https://www.mcmaster.com/4390N142/

Dave
[/quote]

Thanks Dave, very helpful. Back to the drawing board now to fit it in.

Jon
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 07, 2022, 04:07:54 PM
With the Everything shortage  I've had a hard time finding any of these at a reasonable cost.  I hope it gets better with time.

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 27, 2022, 03:31:42 PM
OK  1 step forward, and 3 bask..... :lolb:

If you look at the machined parts above closely, you will see that the gears CAN"T mesh.... :toilet_claw:      :Doh:

OK....drop back and fix it.    I redrew and simplified the pump, .....correctly this time.

I also decided that it nees a lot less volume.   so I gear reduced it...as is prototypical

My gear cutters are here, and I have another piece of bronze!    Off to the mill!!!


Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 28, 2022, 01:28:23 AM
OK   that got it this time!!!   Next will be the pump gears, but if I'm cutting gears, I'm thinking of cutting all of them....as the set up is a bit of a pain in the ass

After second and final ops on these part of course....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on February 28, 2022, 01:57:20 AM
OK  1 step forward, and 3 bask..... :lolb:

If you look at the machined parts above closely, you will see that the gears CAN"T mesh.... :toilet_claw:      :Doh:

OK....drop back and fix it.    I redrew and simplified the pump, .....correctly this time.

I also decided that it nees a lot less volume.   so I gear reduced it...as is prototypical

My gear cutters are here, and I have another piece of bronze!    Off to the mill!!!
I'm confused about the picture in that post, the straight gear on the top shaft, next to the bevel gears, looks to be off to the side of the gear below it? Shouldn't it be meshing with the gear below, like it was in earlier pictures??
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 28, 2022, 02:09:08 AM
OK  1 step forward, and 3 bask..... :lolb:

If you look at the machined parts above closely, you will see that the gears CAN"T mesh.... :toilet_claw:      :Doh:

OK....drop back and fix it.    I redrew and simplified the pump, .....correctly this time.

I also decided that it nees a lot less volume.   so I gear reduced it...as is prototypical

My gear cutters are here, and I have another piece of bronze!    Off to the mill!!!
I'm confused about the picture in that post, the straight gear on the top shaft, next to the bevel gears, looks to be off to the side of the gear below it? Shouldn't it be meshing with the gear below, like it was in earlier pictures??

broken mate.......Fusion is a pain in the ass....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Jasonb on February 28, 2022, 07:23:36 AM
Chris I think it's this pic that shows the pump gears won't mesh as either the ctrs are wrong or the pockets not a big enough diameter.

Would have thought that would show up on the simulation in F360 which basically shows what the machine is going to cut and you could have seen there was not enough gap between the pockets for the gears to mesh.

(https://www.modelenginemaker.com/index.php?action=dlattach;topic=10504.0;attach=132934;image)
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on February 28, 2022, 11:10:03 AM
Chris I think it's this pic that shows the pump gears won't mesh as either the ctrs are wrong or the pockets not a big enough diameter.

Would have thought that would show up on the simulation in F360 which basically shows what the machine is going to cut and you could have seen there was not enough gap between the pockets for the gears to mesh.

(https://www.modelenginemaker.com/index.php?action=dlattach;topic=10504.0;attach=132934;image)

Ah yes....but we all have our days....don't we?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on February 28, 2022, 01:04:23 PM
Chris I think it's this pic that shows the pump gears won't mesh as either the ctrs are wrong or the pockets not a big enough diameter.

Would have thought that would show up on the simulation in F360 which basically shows what the machine is going to cut and you could have seen there was not enough gap between the pockets for the gears to mesh.

(https://www.modelenginemaker.com/index.php?action=dlattach;topic=10504.0;attach=132934;image)
That's not the picture I was talking about, but the one before it showing the cad view with all the shafts and gears.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Jasonb on February 28, 2022, 01:13:24 PM
Yes the large gear next to the bevel is out of place om the main assembly CAD possibly missing a constraint.

But Dave said the pump gears would not mesh, so its inside the pump where the problem is, still not sure if it was gear ctr spacing or hole size but as it looks like all 4 pump parts have been made again probably the former.

I usually find the CAM gets it right and it's me that messes something up like entering the tool height as 200mm instead of 20mm  :'(
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: propforward on February 28, 2022, 05:53:10 PM
I believe Chris means the picture attached here. The gear A (crudely arrowed) should be moved over - which is what Dave was saying - a broken mate. I get that in solidworks plenty, just the same as Fusion 360 I'm sure. The number of times I've put an assembly away, only for it to fly all over the place when I open it the next day..............  :facepalm2:

Two separate things - the cad mate and the actual meshing, I guess.


What an epic thread. I must have not looked in before because it's an I.C. engine - so again  :facepalm:

Really top work Dave, bravo sir. I shall be following along - I have enjoyed catching up with my lunchtime sammo.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on February 28, 2022, 05:56:52 PM
Thats the one Stuart! Sounds like Dave has that one worked out with the broken constraint - fusion does do some odd things with joints sometimes...
And agreed, this design is amazing.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on March 01, 2022, 01:12:37 AM
I believe Chris means the picture attached here. The gear A (crudely arrowed) should be moved over - which is what Dave was saying - a broken mate. I get that in solidworks plenty, just the same as Fusion 360 I'm sure. The number of times I've put an assembly away, only for it to fly all over the place when I open it the next day.............. 

Happens with Alibre too, if you don’t get everything constrained properly.

Dave: many ways to get it wrong, only one way to get it ‘right’.  You’re making progress, regardless of the setbacks.  Looks GREAT.

Back when I was a student in engineering, a student asked the professor once, “Professor, why don’t you give partial credit for test answers that are nearly correct?”.

I loved he’s answer, “When you get it ‘almost right’ the rocket still blows up”. 

Classic!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on March 01, 2022, 04:52:37 PM
I believe Chris means the picture attached here. The gear A (crudely arrowed) should be moved over - which is what Dave was saying - a broken mate. I get that in solidworks plenty, just the same as Fusion 360 I'm sure. The number of times I've put an assembly away, only for it to fly all over the place when I open it the next day.............. 

Happens with Alibre too, if you don’t get everything constrained properly.

Dave: many ways to get it wrong, only one way to get it ‘right’.  You’re making progress, regardless of the setbacks.  Looks GREAT.

Back when I was a student in engineering, a student asked the professor once, “Professor, why don’t you give partial credit for test answers that are nearly correct?”.

I loved he’s answer, “When you get it ‘almost right’ the rocket still blows up”. 

Classic!
I hear ya.    7000 pound load test piece for diamond turning lathe.   The hydrostatic spindles were mine.   
Chucks are 24"

It held the load so my math was right
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on March 01, 2022, 04:55:39 PM
I believe Chris means the picture attached here. The gear A (crudely arrowed) should be moved over - which is what Dave was saying - a broken mate. I get that in solidworks plenty, just the same as Fusion 360 I'm sure. The number of times I've put an assembly away, only for it to fly all over the place when I open it the next day.............. 

Happens with Alibre too, if you don’t get everything constrained properly.

Dave: many ways to get it wrong, only one way to get it ‘right’.  You’re making progress, regardless of the setbacks.  Looks GREAT.

Back when I was a student in engineering, a student asked the professor once, “Professor, why don’t you give partial credit for test answers that are nearly correct?”.

I loved he’s answer, “When you get it ‘almost right’ the rocket still blows up”. 

Classic!
I hear ya.    7000 pound load test piece for diamond turning lathe.   The hydrostatic spindles were mine.   
Chucks are 24"

It held the load so my math was right
Wow. You must have had BIG shop elves!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on March 05, 2022, 04:20:59 PM
OK   Oil pump body parts and covid test today......and a presentation for Monday...........

I did get my gear cutters that I need....

Dave


Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Roger B on March 05, 2022, 05:34:39 PM
With big stuff you usually just get one go so better get it right ::) An impressive lathe.

I can screw things up with pencil and paper or 2D CAD  :(  :facepalm:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on March 05, 2022, 06:00:11 PM
With big stuff you usually just get one go so better get it right ::) An impressive lathe.

I can screw things up with pencil and paper or 2D CAD  :(  :facepalm:

Yeah there was a half a million sunk into the one of a kind spindles alone .....no pressure.....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on March 06, 2022, 11:58:43 PM
First ops complete on the pump parts, and the fixture is made.    Not much to talk about this weekend, but hopefully more this week.    I have the fixture which should allow the second ops on the pump body.   The we cut some gears....

Worked this weekend.......sigh....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on March 28, 2022, 12:40:27 AM
finishing off the vises for the group this weekend, and i'm painting them...perfect time to get some work done on the 917 engine    Oil and scavenge gear pump bodies up to 2nd op   next is to drill the passages....
water bottle cap for reference...

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on March 28, 2022, 01:02:22 AM
More great details.    :popcorn: :popcorn:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on March 28, 2022, 02:33:51 PM
Nice to see you back to making parts.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on March 28, 2022, 04:06:57 PM
Working too many damn hours...
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on March 28, 2022, 10:26:12 PM
Yeah me too. I'm on ten hour days, 7 days a week and we are bout to go to 12 hours.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on March 28, 2022, 10:53:38 PM
Yeah me too. I'm on ten hour days, 7 days a week and we are bout to go to 12 hours.

I remember those days… Being retired it’s a memory, I didn’t say a fond memory either.   :Doh:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Art K on March 29, 2022, 01:59:58 AM
Dave,
Great work on the 917! I had a problem with the assembly on the Offy. I was constraining two flat surfaces and two opposite corner holes on a cover plate. It would only constrain one and would rotate around it. After seeking help on Alibre forum it was found that the holes were .0005 off and didn't match up. I fixed that and all was good. I had been working five 10 hour days since January 2020. I get to quarantine the rest of the week as I tested positive.
Art
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on March 29, 2022, 10:20:02 AM
Art, Craig, Steve and Chris
Be safe out there boys!    and thank you very much for looking in.     Work has been crazy since our new release, and I'm already neck deep in a new project, so at least they want me to stick around.

Art.   It's really hard with these small parts to be assured of geometry.   The best palliative ive found thus far is to do all the machining in one set up.   Even that doesn't always work.    The end cap on the pump doesn't seem very flat, and I suspect it will need to be remade for instance.    Getting 4 parts to string together on a 1/8" shaft is asking for trouble.....
I hope you get through your quarantine uneventfully and get back neck deep in that little Offy.....that's a sweet build!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on April 04, 2022, 11:35:56 AM
Well  It appears I'll be able to save that part, and I've started on setting up to cut the gears for the project.    That includes the pump gears, the pump drive gears and all the cam shaft drive gears.....I think I'm just going to get all that out of the way.  I also need to update my lathe mounted keyway cutter as I've got some keyways to make as well....much to do

I just finished my small part of the vise project with Nigel over at Go Create Hobby Machine Shop on YouTube.      Now that's done, I should have a bit more time.    I want to get the gears done before the good weather really gets here....."Rushforth" has been languishing far too long, and she needs to have her repower completed, and be used!!!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on April 04, 2022, 03:05:10 PM
Quote
"Rushforth" has been languishing far too long, and she needs to have her repower completed, and be used!!!
Glad you're making a bit of headway, sounds like you're a busy boy. So what's this "Rushforth"?
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on April 04, 2022, 04:42:09 PM
Hello Dave

Pleased you were able to take a few moments to look at your hobby interests. It must be hard to remember you are trying to drain the swamp when you are up to your *** in someone else's alligators.

It's good that you have been able to progress the 917's pumps a little and it would be even better if you could get the Yamaha engine into 'Rushforth' with spring and a long summer ahead. Just think, a nice cup of tea and cucumber sandwiches on the river bank or is it a burger and a Budweiser or two?

Any sign of the printed parts?

Cheers

Mike or should that by Myk.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on April 04, 2022, 05:12:33 PM
Not trying to derail but with the current trend it seems a simple transition into electric for the mistress. Maybe a battery pack that can be removed and charged at home. A motor and controller.  Your  not trying to set a speed record so battery life might be better than expected. 
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on April 04, 2022, 06:39:58 PM
Hello Dave

Pleased you were able to take a few moments to look at your hobby interests. It must be hard to remember you are trying to drain the swamp when you are up to your *** in someone else's alligators.

It's good that you have been able to progress the 917's pumps a little and it would be even better if you could get the Yamaha engine into 'Rushforth' with spring and a long summer ahead. Just think, a nice cup of tea and cucumber sandwiches on the river bank or is it a burger and a Budweiser or two?

Any sign of the printed parts?

Cheers

Mike or should that by Myk.

I printed them Miks....gotta get them in a box and off to you

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on April 04, 2022, 06:45:14 PM
 :ThumbsUp: :ThumbsUp:

no rush, they will keep

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on April 04, 2022, 07:15:30 PM
Quote
"Rushforth" has been languishing far too long, and she needs to have her repower completed, and be used!!!
Glad you're making a bit of headway, sounds like you're a busy boy. So what's this "Rushforth"?


Do a forum search under Rushforth and you'll find it
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on April 04, 2022, 08:44:08 PM
Search function on here seems a bit odd sometimes. I did a search for Rushforth and "Rushforth" before asking, and with no result. Then tried again a few minutes ago, again without results, other than today's mentions. Then one more time and found it along with several other mentions which had not shown up previously at all. I have no idea what was different, almost certain not spelling because the "suggestions" that pop up weren't misspelled. :headscratch:
Anyway, Thanks!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on April 04, 2022, 08:47:32 PM
Search function on here seems a bit odd sometimes. I did a search for Rushforth and "Rushforth" before asking, and with no result. Then tried again a few minutes ago, again without results, other than today's mentions. Then one more time and found it along with several other mentions which had not shown up previously at all. I have no idea what was different, almost certain not spelling because the "suggestions" that pop up weren't misspelled. :headscratch:
Anyway, Thanks!
If you were in the thread when you did the search, it just searched the thread, best to be at the forum top when searching. Hope that helps.

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: RReid on April 04, 2022, 08:48:44 PM
That probably explains it, Thanks Chris.
And that's a nice boat, Dave.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on April 05, 2022, 10:27:19 AM
Thanks Ron.    I am currently putting a Yanmar 9Hp single diesel in.     Somehow Mama doesn't feel enamored with sitting in the middle of a pile of firewood.....so I'll be taking a page from the motor lauch Scolopendra
https://www.bing.com/videos/search?q=boat+scolopendra&view=detail&mid=F53E033EE79E5957F6A7F53E033EE79E5957F6A7&FORM=VIRE

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on April 05, 2022, 12:31:45 PM
Hello Dave,

Nice looking hull lines on Scalopendra but not as nice as the long tail 917 bodywork

Just saying

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on April 05, 2022, 02:59:20 PM
Hello Dave,

Nice looking hull lines on Scalopendra but not as nice as the long tail 917 bodywork

Just saying

Mike

Mama and I need a break Mike...  we need to do something together that doesn't involve taking care of a cancer patient.   Been  long 6 years......just sayin
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on April 05, 2022, 11:10:11 PM
Hello Dave,

Nice looking hull lines on Scalopendra but not as nice as the long tail 917 bodywork

Just saying

Mike

Mama and I need a break Mike...  we need to do something together that doesn't involve taking care of a cancer patient.   Been  long 6 years......just sayin

Don't worry boysand girls  I'm not stopping the build or going anywhere.   Just taking advantage of the summer months
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Don1966 on April 05, 2022, 11:43:50 PM
Enjoy to vacation buddy a well deserved one….


Don
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Art K on April 06, 2022, 03:01:54 AM
Dave,
You and the wife take care of yourselves we can wait!
Art
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on April 23, 2022, 09:38:37 PM
Not a huge thing, but I picked up some tooling today for this project.   A 0.8 to 1.25 bore gage.....got a very good price on it too.
This will be for the cylinder bore effort and maybe even the crank bearing bores!....just   1.259

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on April 23, 2022, 11:00:46 PM
Sounds like a great 'find'. Just what you need for accurate bore measurements.

Cheers

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: stevehuckss396 on April 24, 2022, 12:19:18 AM
You will not regret buying it. I started getting them on ebay about 5 years ago. Way easier to measure a bore.


Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Kim on April 24, 2022, 05:23:34 AM
A nice little piece of kit, Dave!

Kim
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: propforward on April 24, 2022, 11:55:32 AM
Nice piece of kit - that will be tremendously useful.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 01, 2022, 11:47:41 PM
Got my bore gage today.    It's sweet!   Needed a touch of cleaning, but it works very well.   I'm going to go find a 1" ring gage master as a check point...

Also picked up a 1-2 mic with tenths vernier and a friction thimble   It checks out accurate....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on May 02, 2022, 12:24:06 AM
   I'm going to go find a 1" ring gage master as a check point...

Dave

If you can find a second 1" ring gauge at a reasonable price, let me know.

Cheers

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on May 02, 2022, 12:49:22 AM
New tools!   :whoohoo:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 02, 2022, 08:28:35 PM
   I'm going to go find a 1" ring gage master as a check point...

Dave

If you can find a second 1" ring gauge at a reasonable price, let me know.

Cheers

Mike

I've seen at least 3 on ebay today in the $20 range used.   I found a 21.4315mm gage, the bore on the 917 engine is 21.488....so close enough to what I'm trying to measure.   ( the bore could be 21.431 just as easily as 21.488    )

I think I paid $43.59 with free shipping and it's still in its sealed wax coating!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on May 02, 2022, 08:40:49 PM

I've seen at least 3 on ebay today in the $20 range used.   I found a 21.4315mm gage, the bore on the 917 engine is 21.488....so close enough to what I'm trying to measure.   ( the bore could be 21.431 just as easily as 21.488    )

I think I paid $43.59 with free shipping and it's still in its sealed wax coating!

Dave

Thanks Dave

Some on ebay UK starting around £40, but all too big a diameter for my gauge. I will keep looking

Mike

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Craig DeShong on May 04, 2022, 04:04:55 PM
New tools!   :whoohoo:

You can never have enough toys.

Great find Dave.
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 09, 2022, 02:31:31 AM
Got some nice pictures of stuff I've not seen a good one for.    Very helpful with respect to the cam covers, the front engine mount/bell housing, and the exhaust pipes
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 09, 2022, 02:33:06 AM
And another
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on May 09, 2022, 02:42:21 AM
That last picture looks like the engine out of a sci-fiction spaceship!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 09, 2022, 03:28:15 AM
Working on Cleaning up the front engine mount.    That last picture really clarifies it.

Getting closer..... 

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on May 09, 2022, 09:14:55 AM
Morning Dave,
Why is it always like that? If you have collected a thousand photos, there are always details that are not visible. That's some good information you found. I like how you were able to use it to refine the front of the 3D model.

Cheers

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 10, 2022, 12:15:12 AM
Oh I'm having some fun....no worries....with all the crap going on in my life....I'll take the little victories.     Much refinement of some of the auxiliaries has been accomplished..   and The front engine mount is coming together in a much more pleasing and accurate way. 

I wish Fusion360 CAD didn't suck so bad...but    first world problem right?

Dave
 
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 16, 2022, 12:04:18 PM
Got a good start on all the internal gears yesterday.  Nothing particularly interesting, as I spent the day making "wafers", but LOTS of wafers

I'll post some photo's later today ....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: propforward on May 16, 2022, 09:18:49 PM
Any time in the shop is a good time.  :ThumbsUp:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 16, 2022, 11:35:27 PM
Any time in the shop is a good time.  :ThumbsUp:

Give me a bit.     need to make a few more waffers!

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 18, 2022, 01:17:44 AM
A little inspiration......Steve doing Steve things

Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on May 18, 2022, 01:34:27 AM
He invented the GoPro??!
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on May 18, 2022, 02:31:10 AM
He invented the GoPro??!
A little inspiration......Steve doing Steve things

Nah   I'd call it a counterweight! 8) :stir:
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on May 18, 2022, 10:47:00 PM
A little inspiration......Steve doing Steve things

He certainly knew how to drive fast and he certainly knew how to make movies. Ground breaking stuff. in it's day

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on June 18, 2022, 05:02:28 PM
Now this was motivational!    I get to print what ever I want at work....could have done this in H13 tool steel.....but it's just for checking fits and my sanity....which always needs checking....

Dave
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Vixen on June 18, 2022, 06:30:44 PM
Hi Dave,

That looks mighty impressive. If you could print it in aluminium; it would save you a lot of time and work filling those buckets with them tiny little chips.

Cheers

Mike
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: Admiral_dk on June 18, 2022, 09:17:18 PM
Good to see the crank in situ (so to speak)  :ThumbsUp:

Some things would be so much easier if we 'could just print them in the correct material'  ;D

Per
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: steamer on June 19, 2022, 02:53:49 PM
Hi Dave,

That looks mighty impressive. If you could print it in aluminium; it would save you a lot of time and work filling those buckets with them tiny little chips.

Cheers

Mike

One material that we CANT print in    Aluminum...to say nothing of Magnesium....
Title: Re: 1/4 scale Porsche 917 180 degree V12 Build
Post by: crueby on June 19, 2022, 11:12:19 PM
Hi Dave,

That looks mighty impressive. If you could print it in aluminium; it would save you a lot of time and work filling those buckets with them tiny little chips.

Cheers

Mike

One material that we CANT print in    Aluminum...to say nothing of Magnesium....
If you can print in chocolate chip cookie dough, I got some business for you!