Another Elmer's #5 Geared Engine

[Krypto]

At first I wasn't going to bother posting a build log of my Elmer's #5 Geared Engine as there already exists a few really nice builds on this site.  I changed my mind, however, as it might provide a few moments of amusement for some of the newer forum readers.



Here are links to two articles about this engine posted by other authors that I found useful:

https://www.modelenginemaker.com/index.php/topic,4087.0.html

by arnoldb as a general build article and

https://www.modelenginemaker.com/index.php/topic,840.0.html

by Inky Engines as I like the look of his version.

Few things, I didn't cut the gears for this engine. While the small external gear is easy, the internal gear is quite challenging to make in the home shop.  I took advantage of a discount code and just bought the gears specified in Elmer's build article, but they weren't cheap and I think they are even more expensive now. Since for me this project is a return to engine making after a several year pause, I didn't want to make it overly difficult and it's been taking long enough anyway.

I've already gotten quite far into the build already and waited to start posting as work and Life tend to really slow down my efforts which will seem glacially slow to many of the members here. However, lately I've been making good progress so by the time I'm caught-up there shouldn't be a long pause to completion.

Next post will feature chips!

[MJM460]

Hi Krypto,

That one is an interesting variation on the conventional crank and conrod style.  Another build log is always welcome.  I for one will be following along.

I am sympathetic to your feeling that some of us take a long time for a build with all life’s usual impediments to speedy progress.  Your plan to build and post later is a good one.  I find I need to write up as I build in a text document, otherwise I forget little details by the time I come to get to posting.  Also a better chance of getting enough photos.  Posting later gives good continuity for the reader.  My current project s almost ready to start posting as I am definitely on the home run, but carer duties have slowed progress to a crawl lately.  But I will get there.

Looking forward to the next episode.

MJM460

[crueby]

Looking forward to your build!




And that kind of geared arrangement is not  just eye candy for modern models, its the k8nd of thing some manufacturers had to do to get around the early steam engine patents, which specified a simple crank arm.

[Krypto]

Yeah, I usually take pictures while I'm working on projects because sometimes you really need them, especially if it's something that needs reassembly.

And that kind of geared arrangement is not  just eye candy for modern models, its the kind of thing some manufacturers had to do to get around the early steam engine patents, which specified a simple crank arm.

Actually I thought it was Elmer just making something that looked different although I'm aware that some of the earlier engine designs had to jump through patent hoops as you mentioned. If anyone has an old picture or diagram of a possible inspiration of this geared engine it would be nice to see it here.

On to the work...



Like most projects, this one starts on the surface plate with the old Starrett vernier height gauge. While these are just reference lines as the DRO on the mill will be used for actually spotting the holes, I tend to practice what I call "defensive machining" as my erratic shop time and small brain make it really easy for me to make bone-headed mistakes. Belts and suspenders for me. In that thinking, to the left of the base is also a 3D printed one for reference as this is the first model that I completely modeled in CAD. With the parts modeled, it was easy to make shop plans that are easier for me to read than Elmer's and of course 3D print a part.  Some people here would just use the CNC mill for the machining as well but I'm not there yet.



Looks like I'm using an end mill for counter-boring the base for the socket head screws (what was that about writing notes?). The 3D printed part makes it easy to verify I'm actually counter-boring the correct side, not like that has ever happened before.  Nope, never did that. 



Using a roughing (or corn cob) end mill for maximum mess to clear the hole for the flywheel in one pass.



And then cleaning-up with a traditional end mill.  Spoiler alert, I'll be coming back to this again as it was a little tight, but that's OK as I would rather be looking at the material then looking for it.



Using a flycutter to clean-up the top of the base.  I'm using one of those small, round carbide cutters (RCMT0602) which work great for this type of work. Later on, I found a RCGT0602 version is also available which is sharper for non-furious metals like aluminum. Kurtis with CEE on Youtube uses this type of round carbide insert often for his much larger work but I've also found the round shape to be very useful in the hobby shop.

[crueby]

While not an internal gear, this page shows one way that the steam engine crank patent claim was circumvented. Interesting stuff!
https://en.wikipedia.org/wiki/Sun_and_planet_gear


This page has more:
https://www.egr.msu.edu/~lira/supp/steam/double.htm


Here is a very early one with internal ring gear that may have inspired Elmer:
https://en.wikipedia.org/wiki/Murray%27s_Hypocycloidal_Engine

[EricB]

Thanks for sharing! That's one from the Elmer's collection I've been wanting to build.

 

Eric

[Krypto]

I would say you research is right on the money with Murray's Hypocycloidal Engine. I imagine that Elmer seen or read about this engine at the Henry Ford museum and used that for inspiration.  Searching with those words leads to quite a few hits.

https://www.thehenryford.org/collections-and-research/digital-collections/artifact/185106

It's different enough from Elmer's version that it's still interesting as an additional subject to model.  I like the look of the piece at the Henry Ford museum more than the one at Birmingham.

Watt used the sun and planet gear arrangement to work around the crank patent, while Murray used the hypocycloidal gears to work around Watt's patents.  The patent office was quite the minefield back in those days.

[crueby]

I would say you research is right on the money with Murray's Hypocycloidal Engine. I would imagine the Elmer seen or read about this engine at the Henry Ford museum and used that for inspiration.  Searching with those words leads to quite a few hits.

https://www.thehenryford.org/collections-and-research/digital-collections/artifact/185106

It's different enough from Elmer's version that it's still interesting as an additional subject to model.  I like the look of the piece at the Henry Ford museum more than the one at Birmingham.

Watt used the sun and planet gear arrangement to work around the crank patent, while Murray used the hypocycloidal gears to work around Watt's patents.  The patent office was quite the minefield back in those days.

I never even saw the truck... 


Patents are still a minefield!

[Brian U]

Will be watching your build for sure. What is your plan for the gears ?

[Krypto]

As mentioned in the first post, I already bought both gears awhile ago.

Onwards...



Here I'm using the lil Dake to press oilite bearings into the bearing holders. The important holes were spotted using the DRO on the mill, while the cosmetic outer features were milled to a line and then finished with a file or belt sander.



Back at the lathe, here the flywheel is being centered in the 4 jaw chuck and it's a PM Research casting, specifically the FWC-S7 #7 Flywheel Casting.

The red paint is something new to me as it is powder coated.  A coworker does advertising laser work on the side and previously he powder coated his cups himself but nowadays buys them ready-to-laser.  He casually mentioned that he was selling his powder coat gear and gave me a sweet deal on his entire kit.  I'm still learning but I was able to get this flywheel coated and successfully cooked-off in the shop's EasyBake toaster oven. The great advantage of powder coat paint is it's durability. No problems machining this flywheel with no scratches or chips in the coating.



Here I'm drilling for the set screw without removing the flywheel from the chuck. The drilling device is basically a small chuck attached to a 1/2" shaft which is turning inside a long bronze sleeve. You move the shaft forwards and backwards while using a cordless drill to make the hole. The device is fastened to a QCTP holder so it's easily removed for access to change drills or taps.



After the drilling and tapping for the set screw the axle hole is cleaned-up and finalized with a reamer.



The lil Dake was used to press an arbor into the flywheel and then it is turned to size between centers. It's only a 1/4" arbor so very light cuts were used. When machining a flywheel, I try to use maximum effort to insure concentricity as the first and only thing most people will notice with a model engine is if the spinning flywheel is all pissed and wobbly.



It's coming together.

[Krypto]

Back on the build, here I'm starting on the cylinder.  Due to it's relative complexity, it's the most interesting part on the model. I started with a nice hunk of brass and faced it off on all sides. 



Here I'm center-pointing the cylinder location which, by the way, is not in the center of the piece so the DRO on the mill was used to find and spot the offset location.



Back at the lathe, the drilled point is centered in the 4 jaw chuck using the dead center technique.



And then the hole is opened with a drill.



The cylinder is almost 3 inches long but only has a 1/2" hole which is kind of long for the size.  I could have reamed it, but I was able to make this small carbide insert boring bar just do the job.  The finish inside the hole was excellent.



Facing off the front of the cylinder.  It's always a good idea to face off the inboard face of a cylinder in the same setup as the hole was made because you'll never get the two features more perpendicular.



The cylinder was turned down to the plans and here you can plainly see the hole offset.  I also marked this side red to make sure it's used for the inboard head. The cylinder was then flipped around in the chuck and the other side was turned down.

[Saxalby]

I am a great fan of Elmers engines but can't seem to find any link to the plans for this engine. Can anyone help.

Reagrds Barry

[PaulR]

Facing off the front of the cylinder.  It's always a good idea to face off the inboard face of a cylinder in the same setup as the hole was made because you'll never get the two features more perpendicular.

Great photos and descriptions and I'll try to remember this top tip!

[Krypto]

I am a great fan of Elmers engines but can't seem to find any link to the plans for this engine. Can anyone help.

Try here:

https://www.myheap.com/metalworking/resources-downloads.html

[Saxalby]

Many thanks for the link

Regards Barry

[Krypto]

Continuing with the cylinder, we are back at the mill cutting the exhaust ports with a 3/32" end mill. I'm holding that end mill in a stubby ER11 extension which is very handy as it gives you enough visual clearance so you can see what you are doing compared to holding the tiny end mill directly in the spindle.  I also have a longer ER11 extension for drilling holes in hard-to-reach places.



Drilling the exhaust passage from the cylinder face to the exhaust port which is always a tense moment.  The drilling angle suggested by Elmer worked fine and the small brass sheet is inserted into the exhaust port while drilling so you can easily feel when the drill breaks into the port.



Drilling the bolt hole circle for a cylinder cover using the DRO.



This is what the PCD function looks like on this DRO which I think is a bit more intuitive than the older displays that only feature a numerical output.



Awhile ago I milled the bottom of this Spindexer so it would sit accurately in the vise.  Here I'm using it to mill the cosmetic rounded part between the cylinder faces. It's not really made for this type of work, so take lights cuts and mill slowly as you don't want to spoil the work this far into the job.

[Admiral_dk]

Great setups - inspiring 

The Parts you are making looks good too 

Per       

[Krypto]

Thanks!  It's getting there...

[Krypto]

For the steam chest, a brass bar was held in the 4 jaw chuck at the lathe.  Made the round bit with a file on the outboard side and it came out good enough on the first try.



The proto steam chest was then flipped over, turned to length and the other end machined.  Drilled the 1/16" hole almost to the end of round bit on the other side which wasn't exactly fun.  Might have been better to mill out the inner part and then drill these holes at the mill.



The steam chest getting opened-up at the mill.



While the 4 jaw chuck was installed, the eccentric was setup and then machined.  I always enjoy making these as it seems somewhat magical while you are turning the offset.

[Krypto]

Working on the valve rod.  One thing I wanted to show is that it's usually difficult to turn such a long, thin rod without some form of support.  In fact, the first time I turned the rod down using multiple passes it snapped off from the parent stock.  This time I used a technique I seen described elsewhere which was to take it all in one shot.  So at first I just turned down the corners of the square bar to get a good measure and then the rest was removed in one pass.  It worked great with the valve rod measuring right on dimensions throughout it's length.



Using the Neil Butterfield inspired sliding tap/die holder for threading at 2-56.



The valve rod nut needs to fit nice and tight.



Working on the gear arm at the rotary table.  Tried out a new rotary fixture plate during this project and found it worth the bother of making it.



Some more clean-up of the gear arm at the lathe.  This will be soldered onto the orbiting gear.

[Krypto]

The orbiting gear needed a tiny bit of machining, so for some reason I decided to make a custom aluminum fixture to hold the gear. While I was machining the gear hub down, that expensive gear popped out of the fixture and one of the teeth got nicked a bit with the lathe cutter. 

Much profanity was issued! 

After I calmed down, the fixture was trashed and I just held the gear in a ER32 collet after straightening it with a ball bearing pusher and that worked great.  Sometimes I make unnecessary grief for myself!  I cleaned-up the gear with a file and hid the dinged tooth behind the gear arm so it's not really noticeable.  Whenever I setup the gears in the bearing holder, however, I noticed a slight tight spot while turning the crankshaft.



One would think the factory gears would be perfect, so probably the tight spot was my fault from the problem described above.  In any event, some lapping compound on the gears and less than a minute's work with a drill turning the crankshaft totally solved the problem.



I used the Timesaver lapping compound which is nice because it's guaranteed not to embed into softer materials. It comes as a powder that is then mixed with oil for use.  The test kit shown is an assortment of lapping compounds for both hard and soft metals and should last the average modeler a long, long time.  I tried to make the moving parts, like the eccentric / eccentric strap fit, a tad on the tight side and then used the lapping compound while working the parts for a perfect fit.  I think this is a more civilized approach than some of the madmen on Youtube who "break-in" their engines by turning them strapped to a lathe for hours on end.  Madness! 



Finishing off the valve.  Originally the valve was a bit too high to fit properly (assumed a dimension), but it was an easy fix as the bottom just needed a bit milled off.  The valve nut was installed so the nut wouldn't get squashed while being held in the vise.  By the way, that's a smaller vise held with the regular milling vise as the valve nut is under a 1/4" square.  You know when the ER11 collet looks big that the parts are getting small.



Getting parts attached to the cylinder. I'm using the Loctite thread sealer to "glue" the valve plate and steam chest to the cylinder in the proper location that way I can loosen the bolts to remove the valve cover and not have those parts loose their location.  Eventually I will switch to a clear acrylic cover to see the valve moving as shown in Inky's engine.  If you look closely at the valve plate you can see some polishing from the valve.  Looks like it's running right on the money!

[crueby]

Glad you were able to recover from the 'incident'!  Engine is looking great.   
I love that timesavers compound, the test kit just has small tins of each grit/type, but for our uses the tins are enough for many many models, I've been using it for years and the tins are still at least 90% full.
 

[Krypto]

Thanks!  I think it was worth it to splurge for the extra brass.

Yes, I used one tiny pinch of powder from one tin and that did everything.  A little bit goes a long way.

[Krypto]

Punching out the cylinder gaskets in one hit with a dual-head Mayhew hollow punch.  Bought this set used because it's made in France and somewhat salty here in the states.  Excellent kit if you see one.



More work on the gaskets.  I had bought one of those leather punch tools to try for the small holes but totally forgot about it.



Decided I wanted to round-off the end of the piston rod but didn't want to take it apart as the rod packing was set and everything was working correctly so I made a filing button.  Bit of work, but they are an almost idiot proof way of rounding parts like this.



Reaching the end of the build so I'm replacing the Phillip screws I was using during the build with studs which are just nuts loc-tited to a piece of threaded rod.  All the nuts I used on this model were 2-56 narrow-profile bought from McMaster-Carr.  I'll also be adding wood lagging to the cylinder.

I will be wrapping-up the engine build in the next post!

[Krypto]

The completed Elmer's #5 Geared engine.  Here you can see the doll house planking used as cylinder cladding for a cosmetic touch as shown in Inky's build.  I just used CA to attach the planking as I'm not planning on running this engine on steam.



The acrylic valve cover is yet another idea from Inky's build.  It's interesting to watch the valve working while the engine is running which nicely complements the trick gear arrangement on the other side.

<a href="https://www.youtube.com/watch?v=I2T6dQtQzho" target="_blank">http://www.youtube.com/watch?v=I2T6dQtQzho</a>

A short video composed of three different views of the engine running on air.

Overall it was a very enjoyable build without any major difficulties.  Elmer's drawings were spot-on and the engine ran well even at the first assembly.  Probably the most important new technique (for me) used during the construction of this engine was modeling the project in CAD and then using that model to produce shop plans or 3D printed components for reference. That definitely reduced the bone-headed mistakes.

[crueby]

A real beauty!  The motion of the crank/gear is just mesmerizing too.

[Krypto]

Thanks! It is interesting to watch while running.

[ShopShoe]

Congratulations on a beautiful engine.

I like the bling. I especially like the lagging: It definitely adds to the beauty of the whole engine.

As has been said, the motion while running is mesmerizing.

Thank You for posting.

ShopShoe

[RReid]

That's a really nice looking little engine. Well done!

I like the acrylic cover for the valve chest. I too did that when I built the #43 Mill engine; always like to see the "works"!.

[Krypto]

Thanks guys!  This forum was an incredible asset while making this engine.