Author Topic: Enlarged Rocking Engine Build (Read 22105 times)

Ross · « **on:** August 24, 2012, 11:52:24 PM »

Hi everyone,

I started a new project on my lathe today. I'm building a enlarged version of the rocking engine, designed by member NickG on here. His original build :

http://madmodder.net/index.php/topic,1718.0.html

I will be making a few artistic changes to the original plans it won't be a fast build though! Sadly I don't have much time to get to The shed at the moment do bear with me!

I didnt get much done today, I had to make a Gear knob for my dads new car it took longer than expected due to my tail stock failing. I need to strip it tomorrow as the part that extends when you turn the wheel has come loose and is slipping. The madmodder link for the knob is below for those that are interested!

http://madmodder.net/index.php/topic,7540.0.html

Anyway, I faced all of my stock and turned the cylinder to length.

I also started on the cylinder cover, I turned it to the correct diameter. It needs to be marked out for the 6 equispaced holes next.

Tommorow I think drill and bore the cylinder and Lap it to size, but I shouldn't get ahead of my self!

Fasten your seatbelts, it's going to be a long ride!

Ross

swilliams · « **Reply #1 on:** August 25, 2012, 01:03:49 AM »

I'm on board for the ride Ross

Steve

zeeprogrammer · « **Reply #2 on:** August 25, 2012, 01:07:44 AM »

Quote from: swilliams on August 25, 2012, 01:03:49 AM

I'm on board for the ride Ross

Same here. I have no idea what a 'Rocking Engine' is...will enjoy watching this.

Dean W · « **Reply #3 on:** August 25, 2012, 06:57:47 AM »

Great to see you on a new engine, Ross. Build number two, here we go!

NickG · « **Reply #4 on:** August 25, 2012, 08:37:51 AM »

I'll definitely be watching here too! We won't spoil it for you then Zee - see if you can spot how it works as the project unfolds!

Nick

zeeprogrammer · « **Reply #5 on:** August 25, 2012, 01:11:01 PM »

Apologies Ross. Somehow I didn't see the links.

Nick...nice project!

Looking at the link hasn't spoiled it for me though.

Besides, I enjoy the journey as much or more than the destination.

Ross · « **Reply #6 on:** August 25, 2012, 05:06:33 PM »

Hi everyone,

Thanks for the comments!

Today I marked out the holes on the cylinder cover and drilled them.

It was very hard to do on my pilar drill and it took some lining up. I think I moved in a bit to far in while marking the PCD I will have to make the bore of the cylinder smaller by 2mm.

Next, I cut the stock and faced to the required thickness and drilled and tapped M5:

I finish turned the cylinder cover, and adjusted it slightly to Make it easier to drill the holes in the cylinder. The only thing I didn't do was put a recess for a seal as I'm not sure of the size of the one I'll use.

Next I turned the outer diameter of the cylinder, turned the majority first.

And then turned it in the chuck and finished all the way.

Next I drilled the bore to 13mm

And then bolted The cylinder plate and cylinder together ready for drilling and tapping.

Ross · « **Reply #7 on:** August 27, 2012, 06:22:05 PM »

Hi guys,

I drilled and tapped the holes in the cylinder, I messed up the centre punches on the first try hence the extra set.

I drilled the bore to the final diameter and lapped.

That's all I got done today due to my lathe having a blip! I made a little start on the piston I'll finish that this weekend hopefuly.

Dan Rowe · « **Reply #8 on:** August 27, 2012, 06:57:07 PM »

Quote from: Ross on August 27, 2012, 06:22:05 PM

I messed up the centre punches

Nice save.

I usually find out I goofed after I have drilled the holes.

Dan

Jo · « **Reply #9 on:** August 27, 2012, 07:11:16 PM »

Did you center punch through the cover holes? You could have used the cover as a drilling guide, the trick being to only drill a dimple and then use that as the guide for your tapping drill later.

I see you used a bolt to keep the cover in place whilst marking. I normally super glue the cover in place, drill a dimple using the clearance drill before replacing it with the tapping drill and then tapping for the first mounting stud, then add a bolt down that hole to stop anything moving before drilling and tapping the remaining mounting holes.

Jo.

Ross · « **Reply #10 on:** August 27, 2012, 07:22:55 PM »

Quote from: Jo on August 27, 2012, 07:11:16 PM

Did you center punch through the cover holes? You could have used the cover as a drilling guide, the trick being to only drill a dimple and then use that as the guide for your tapping drill later.

I see you used a bolt to keep the cover in place whilst marking. I normally super glue the cover in place, drill a dimple using the clearance drill before replacing it with the tapping drill and then tapping for the first mounting stud, then add a bolt down that hole to stop anything moving before drilling and tapping the remaining mounting holes.

Jo.

Yeah I centre punched and drilled through the cover but it moved so I had to try again!

NickG · « **Reply #11 on:** August 28, 2012, 01:45:41 PM »

Nice work Ross, the bore looks good, If you get a decent fit on the piston it should work a treat - mine was pretty sloppy. The trick is not to have any tightness - bit of clearance is better than it being a bit tight.

Nick

Ross · « **Reply #12 on:** August 31, 2012, 06:04:54 PM »

Hi Guys

Not munch done today, just got myself into a bit of a pickle on the piston.

While roughing out I thought to myself , why the hell did I face it to length? It would have been 10x easier to make then.

Im finding it hard clamp it to turn it to size, so I think I may scrap this and order a new bit of stock and redo it.

The diameters on the far left and right are .0010" off finish size, but I'm left with noting to clamp onto for the middle!

Live and learn!

Ross · « **Reply #13 on:** August 31, 2012, 11:39:32 PM »

I remembered I had another piece of brass long enough so I've just made another!

I made the piston a little bigger on this one so it gives me lots of room to play with for the radius on it.

swilliams · « **Reply #14 on:** September 01, 2012, 01:01:01 AM »

Looks nice Ross. What's the large diameter on it? Just trying to get an idea of the scale of the thing

Steve

Ross · « **Reply #15 on:** September 01, 2012, 01:12:44 AM »

Quote from: swilliams on September 01, 2012, 01:01:01 AM

Looks nice Ross. What's the large diameter on it? Just trying to get an idea of the scale of the thing

Steve

Thnks Steve

The o/d of the cylinder is 1 inch.

And the ID is .511 inches.

I'll try and remember to take a photo of the parts next to a coin or something, but there's not many of them about!

Ross · « **Reply #16 on:** September 02, 2012, 12:18:50 AM »

Hi everyone.

Today I put the radius onto the piston and made it fit the bore.

It was VERY easy to go undersize, the piston fits and turns in the bore nicely its not as snug as it probably could be but I think it should be good enough I can always adjust when it is all together.

zeeprogrammer · « **Reply #17 on:** September 02, 2012, 12:38:24 AM »

Looks really good Ross.

swilliams · « **Reply #18 on:** September 02, 2012, 12:48:33 AM »

Yes - coming along nicely Ross

Quote from: Ross on September 01, 2012, 01:12:44 AM

I'll try and remember to take a photo of the parts next to a coin or something, but there's not many of them about!

hopefully that improves in the not too distant future!

Steve

NickG · « **Reply #19 on:** September 02, 2012, 08:22:21 AM »

Or use an M&M - it's an international standard of scale!

Ross · « **Reply #20 on:** September 23, 2012, 04:23:38 PM »

Hi everyone,

Today I made two crank wheels. They just need the off set hole drilled through the for the crank pin.

I also shortened the bolts for the cylinder plate.

NickG · « **Reply #21 on:** September 23, 2012, 08:05:41 PM »

Nice 1 Ross, getting there.

Ross · « **Reply #22 on:** October 20, 2012, 08:18:49 PM »

Hi everyone,

Finally got back onto this today.

First I made a mandrel for clamping the crank wheels while drilling the offset holes.

I drilled the first hole with no problems. But on the second I over tightened the nut and stripped the thread, I had to put the 3 jaw back on and skim the face.

Clocked and drilled.

Then I drilled the holes for the grubsrews to fix onto the crank. And. Threaded M3.

NickG · « **Reply #23 on:** October 20, 2012, 09:07:28 PM »

Good work there Ross, glad to see you back on it

arnoldb · « **Reply #24 on:** October 22, 2012, 07:02:52 PM »

Good to see you back on the build Ross

If I may offer a couple of suggestions...
When possible, have the flange section of the workpiece press against the headstock end of the mandrel - that adds additional friction, and will also leave a hole with less burrs to remove after drilling. It also means you don't have to clamp down that tightly on the nut and strip out the threads, and with a piece of ordinary photocopy paper squashed in between at the chuck end, you'll get an even better friction fit with even less torque needed on the nut. It will also eliminate flex on the screwed section, and you will end up doing a more accurate job. And lastly, rather than threading the entire section on the mandrell, turn most of it to a good fit for the hole in the workpiece, and thread it to leave only a couple of thread turns inside the workpiece to allow you to tighten it down. Threaded sections are usually smaller in diameter than the actual hole, and having an entire threaded section adds a lot of unnecessary slop. Just a couple of very cheap cents from my part of the world

Kind regards, Arnold

Ross · « **Reply #25 on:** November 01, 2012, 08:24:12 PM »

Quote from: arnoldb on October 22, 2012, 07:02:52 PM

Good to see you back on the build Ross

If I may offer a couple of suggestions...
When possible, have the flange section of the workpiece press against the headstock end of the mandrel - that adds additional friction, and will also leave a hole with less burrs to remove after drilling. It also means you don't have to clamp down that tightly on the nut and strip out the threads, and with a piece of ordinary photocopy paper squashed in between at the chuck end, you'll get an even better friction fit with even less torque needed on the nut. It will also eliminate flex on the screwed section, and you will end up doing a more accurate job. And lastly, rather than threading the entire section on the mandrell, turn most of it to a good fit for the hole in the workpiece, and thread it to leave only a couple of thread turns inside the workpiece to allow you to tighten it down. Threaded sections are usually smaller in diameter than the actual hole, and having an entire threaded section adds a lot of unnecessary slop. Just a couple of very cheap cents from my part of the world

Kind regards, Arnold

All good points Arnold, and I'll use them next time around!

Ross · « **Reply #26 on:** November 01, 2012, 08:24:22 PM »

Hi everyone,

I ordered some aluminium for the engine frame a while ago, and it arrived today

I had a go at filing the edges of the engine frame square. And being probably the worst filer in the world even using a square and taking off the high spots, I was tearing my hair out! I don't think I can get any straighter than what I've ended up with!

The only problem being is that the rectangles are now 2x1.5 inches they need to be 2x1.25 I don't particularly fancy trying to file the longer edge square but I'm worried that the extra .250" height will dwarf everything else! Ideas?

Ross

Bezalel · « **Reply #27 on:** November 01, 2012, 10:03:45 PM »

Hay Ross

There is probably more experienced guys who could improve on my suggestion but you could stack the two plates together side by side in the 4 jaw, two jaws on each side off the stack, then face off ( use HSS as its an interupted cut) reduce to about 1.3" then flip them over ensuring they are flat against the chuck face then take off another 50 thou - hay hay! flat, parallel, square and correct size.

Bez

dalee · « **Reply #28 on:** November 02, 2012, 02:31:47 AM »

Hi,

I can also vouch for that method. I've done things like that a few times and it's fast and accurate.

dalee

steamer · « **Reply #29 on:** November 02, 2012, 07:48:06 AM »

Wot Bez and Dalee said!

Let the lathe do the filing!....

Dave

NickG · « **Reply #30 on:** November 02, 2012, 11:42:38 AM »

Never thought of that! I have forgotten how useful the 4 jaw can be since I got milling machine - and my 4 jaw is too big!

Ross · « **Reply #31 on:** November 04, 2012, 05:06:34 PM »

Hi everyone,

I got quite a bit done today, I followed the advice given and took the aluminium plate down to size and it s square and fat!

Then I marked out the holes on the plate.

And then drilled.

And then I marked out and drilled the holes in the bottom ad tapped M4

And then I rubbed the faces and sides down with sandpaper to remove the marks etc..

And loctitited the bearings in the holes flat.

And while that was drying I turned and finished the crank shaft diameter.

All in a days work!

Ross

Stilldrillin · « **Reply #32 on:** November 04, 2012, 05:50:53 PM »

Nicely done Ross!

That toolpost looks right at home there...........

David D

Bezalel · « **Reply #33 on:** November 04, 2012, 09:41:38 PM »

Quote from: Ross on November 04, 2012, 05:06:34 PM

Hi everyone,

snip > the aluminium plate down to size and it s square and fat! < Snip

Ross

oops!

you're supposed to feed the tool into it, not cottage cheese

But nicely done !

Bez

Ross · « **Reply #34 on:** November 04, 2012, 10:48:55 PM »

Quote from: Bezalel on November 04, 2012, 09:41:38 PM

Quote from: Ross on November 04, 2012, 05:06:34 PM
Hi everyone,

snip > the aluminium plate down to size and it s square and fat! < Snip

Ross

oops!

you're supposed to feed the tool into it, not cottage cheese

But nicely done !

Bez

I am a incredibly in accuate typer! And sometimes auto correct dosent pick up the pieces.

arnoldb · « **Reply #35 on:** November 05, 2012, 04:50:15 PM »

Quote

All in a days work!

A good day's work at that Ross - good going

Kind regards, Arnold

NickG · « **Reply #36 on:** November 05, 2012, 07:49:13 PM »

Yeah nicely done Ross - still kicking myself at not thinking to do it in the 4-jaw!

V 45 · « **Reply #37 on:** November 05, 2012, 10:43:35 PM »

Looks like it's going well for for you Ross. I really like the 4 jaw concept !!
Well done...
Dave

Ross · « **Reply #38 on:** November 23, 2012, 06:46:56 PM »

Hi everyone,

I've taken another few weeks off on this but I've been busy doing a couple of bits and pieces to my lathe, I've fitted a new guard and a lamp which I made, the light makes a world of difference.

To test it out I had to turn some sleeves for the I/D crank wheels due to me stupidly ordering 5mm bore bearings and drilling the crank wheels to 6mm

I turned he O/D to suit the bore of the wheels and then drilled the bore 5mm and parted off two parts. there isn't much material in it and I thought it was going to all end in tears, but I'm pleased with the result. Just a couple of holes to drill for the grub screws to slot through.

Stilldrillin · « **Reply #39 on:** November 25, 2012, 08:46:40 PM »

Hi Ross.
One good thing about owning a lathe....... You can put right the muck ups, you've made with your lathe......

I like your chuck guard. It stops a spotty stripe appearing, downwards from your left shoulder.

I made mine from a piece of alloy chequer plate. Formed over a 6" dia log.

Must get meself one of those lamps, to shine into bores........

David D

Ross · « **Reply #40 on:** December 01, 2012, 03:04:15 PM »

Hi everyone,

Today I started roughing out the support posts that will go between the engine frame and the base.

I have to make 5 of these so I changed the design to keep it simple and so there less margin for error.

Here is a rough drawing, I left the diameters off as I didn't have the measurements on hand. I'm trying to use imperial measurements more and more, but all the threads are still in metric!

Firstly I parted each post off and roughed out the thread length at the top. This varied slightly per part so I could keep the length of the body the same.

I left the main body of the posts .300" long for ease of clamping.

I drilled the 4.2 mm holes in the bottom of each post for the M5 Thread.

And then I started to turn the O/d of the thread length I marked out previously to 4mm and threaded.
From here, it all goes downhill.

I decided to face the first off to length - .500" and it was all going well as it should. I turned the top half O/D of the part down to 6.25mm.

I went in for the finishing cut of this O/D and was just winding out at the back face when I accidentally knocked the feed on. The part partly sheared out of the jaws and the cutting tip of the tool snapped off. Sadly this mangled the part and the tool beyond repair.

I continued on with the next part and did the above, I was using a new tool and I was having major problems with the clearances as it was rubbing while I was facing it to length. It works fine when cutting the O/D's though. The tool I'd broke worked I'd never had a problem with the grinding clearances but I really can't get the hang of grinding these bigger tools.

I've left it for now as I didn't want to go scrapping all the rest off because of badly ground tools. Maybe a interchangeable tip tool would be a good Christmas present?! But I'll see what you guys think.

Ross

Ross · « **Reply #41 on:** December 01, 2012, 03:06:55 PM »

Quote from: Stilldrillin on November 25, 2012, 08:46:40 PM

Hi Ross.

Must get meself one of those lamps, to shine into bores........

David D

The lamps are very cheap, I've noticed that B&Q do a flexible clip lamp for ?8 That might be worth a look!

Stilldrillin · « **Reply #42 on:** December 01, 2012, 05:48:53 PM »

Quote from: Ross on December 01, 2012, 03:06:55 PM

Quote from: Stilldrillin on November 25, 2012, 08:46:40 PM
Hi Ross.

Must get meself one of those lamps, to shine into bores........

David D

The lamps are very cheap, I've noticed that B&Q do a flexible clip lamp for ?8 That might be worth a look!

Wilkinson's..... Looks just like yours, round base ?4.99.

But you don't get a bulb!

David D

NickG · « **Reply #43 on:** December 02, 2012, 09:25:13 AM »

Ross,

Shame about the little mishap. Don't worry, similar things happen to us all - well me anyway!

Are those tungsten carbide tipped tools you are using? I get better results using high speed steel tools. For aluminium, as it is quite soft you need a large top rake angle - up to 40 degrees but you'll probably find anything from 20 works ok.

You then need a small angle coming away from the workpiece from every other direction. Make these fairly small to keep the rigidity. Nice sharp point with a tiny rad on the end, I usually don't try to grind that on, just make sure there are no burrs with an oil stone. If it feels like it's going blunt, a few rubs with an oil stone will do.

This is a pic I showed for a tool that turns a radius in a flywheel (steel so about 20 degree top rake), the idea is the same but you won't need the curved side to clear the recess as you're not making one!:

NickG · « **Reply #44 on:** December 02, 2012, 09:31:59 AM »

Another observation if I may - there are obviously lots of different ways of doing things, but the way I'd do this would be to leave the material on the parent stock for as long as possible.

So rather than parting off your 4 lengths, I'd face the end of the bar, turn the intermediate diameter to the right distance from the end of bar, turn the thread diameter to the right distance from the end of the bar, put the thread on, part off to correct length. Do this for all 4, then put them back in the chuck the other way around to drill and tap one by one.

steamer · « **Reply #45 on:** December 02, 2012, 11:37:11 AM »

Quote from: NickG on December 02, 2012, 09:31:59 AM

Another observation if I may - there are obviously lots of different ways of doing things, but the way I'd do this would be to leave the material on the parent stock for as long as possible.

So rather than parting off your 4 lengths, I'd face the end of the bar, turn the intermediate diameter to the right distance from the end of bar, turn the thread diameter to the right distance from the end of the bar, put the thread on, part off to correct length. Do this for all 4, then put them back in the chuck the other way around to drill and tap one by one.

+1 for this and using HSS tools. The 7X lathes are light lathes compared to industrial stuff. Top rake will reduce the cutting forces dramatically. Your lathe...and you...will be happier.

Lots of top rake for Aluminum.....like 20 degree's if you can
About 12-15 degrees for steel
NONE for brass or Bronze....and you can run some negative rake with bronze....

Keep the tool sharp...and spend some time with a small oil stone and polish the cutting edge.....you will be surprised how well it cuts.

Dave

Ross · « **Reply #46 on:** February 02, 2013, 02:08:34 PM »

Hi everyone,

After an extended Christmas break due to passing my driving test I'm back to hopefully finish this one off before I forget how to use a lathe! I ordere some more metal and sorted my tool troubles out with the help of stilldrillin.

I nipped down to the shed after work and got 2 of the 4 engine posts finished and the other two just have to be faced to length.

Ready to be parted off:

2 finished.

2 still to face to length!

b.lindsey · « **Reply #47 on:** February 02, 2013, 02:36:39 PM »

Hi Ross, nice to see you back at it again.

Bill

zeeprogrammer · « **Reply #48 on:** February 02, 2013, 03:00:19 PM »

Congratulations on the driving test.
Glad to see you're back at the lathe.

NickG · « **Reply #49 on:** February 02, 2013, 03:51:25 PM »

Nice 1 Ross, not far off now

Ross · « **Reply #50 on:** February 02, 2013, 04:47:19 PM »

Thanks guys,

I Got a lot done today.

I cut out a sqaure of aluminium, 1.25" x 1.25"

Squared the sides up using the old reverse milling technique.

Marked out the hole for the bore of the cylinder. 0.625 in each way.

Clocked it in

I drilled the hole to 5mm and bolted the cylinder cover plate to the square so I could use it as a guide for drilling the holes.

I then drilled the holes using my pillar drill.

Then I clamped the cylinder cover to one end of the the cylinder and the square to the front so I could drill and tap the holes on the cylinder.

Ready to drill:

Job done:

After, I marked out and drilled and tapped the holes in the sides of the square so it bolts onto the two other engine frames I made earlier.

And then it was back onto the lathe to drill the bore to match up with the bore of the cylinder.

Job done!

Just need to order some more bolts so I can assemble it all!

NickG · « **Reply #51 on:** February 02, 2013, 06:04:42 PM »

Great stuff, looks better than mine did.

Ross · « **Reply #52 on:** June 28, 2013, 04:53:37 PM »

Hi Guys,

Little bit quiet on this one to say the least. I've been doing bits and pieces along the way and I've nearly finished this engine (finally)

This is the mockup in its final stages:

As you can see I'm nearly there Just the crankpin and some flywheels to make.

I made a couple of flywheels but I wasn't happy as I felt they were too small.

And I'm currently in the process of making an air adapter to screw in the back.

I hope everyone is well.

Ross · « **Reply #53 on:** June 28, 2013, 04:54:21 PM »

Just the finishing touches now, machined the air adapter and crankpin!

More metal for the flywheels is on its way!

Ross

Ross · « **Reply #54 on:** June 28, 2013, 04:55:11 PM »

The metal arrived for the flywheels, so I set about making a couple!

Roughed out.

Then onto the mandrel to skim the o/d

I went to drill the holes for the grubs crews, and I managed to snap the crap vice I was using on the pillar drill!

Here is the final mock up! the crankshafts need to be faced slightly shorter. Not sure weather to leave the flywheels plain, I quite like them as they are now.

Ive already test ran the engine! too much air pressure is getting through as I cant control it very well with the attachment I'm I need to find something where I can have full control over the air going into the engine.

b.lindsey · « **Reply #55 on:** June 28, 2013, 05:01:28 PM »

I like it Ross...hope once you get the air supply issue worked out you can post a short video of it running. Nice job!!

Bill

NickG · « **Reply #56 on:** July 01, 2013, 09:13:00 AM »

Yeah, video would be great!

steamer · « **Reply #57 on:** July 01, 2013, 12:07:48 PM »

Wot they said!.....vids please!

arnoldb · « **Reply #58 on:** July 01, 2013, 05:45:41 PM »

Looks good Ross

I must honestly say that's the first time I saw a bench vise mounted to a drill press

Might be a tad heavy though

Kind regards, Arnold

ths · « **Reply #59 on:** July 02, 2013, 11:54:08 PM »

The engine's looking great, Ross. Thumbs up on the vice, and as Arnold alluded, it must have been fun to align.

Cheers, Hugh.

News:

Author Topic: Enlarged Rocking Engine Build (Read 22105 times)