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.