A Celebratory Engine -Elmer's #8

[arnoldb]

Thanks Bill. Its become second-nature for me to have a couple of different grade sheets of emery lying about on a flat surface; as I finish machining each piece, I nearly subconsciously deburr it with a fine file and give it a rub-down on the emery. It helps that I'm getting better machined finishes; less elbow grease :big:

Mel, thanks. I don't know and can't measure the RPM. At a guess that was about 2000 to 3000 RPM at 40 psi - It still wants to go but I'm scared it will break apart as the crank pin is just 1.5mm (just under 1/16") thick and this particular engine design is very out of balance.

Baie Dankie Wagner ;D - Believe me, your 2 hours are more golden than mine; enjoy the missus and the kids - the hobby is a side-line. And once the young ones are bigger, you'll get to spend quality time with them in the shop; better start searching for safety glasses for kids - might be hard to come by in RSA ;D

Regards, Arnold

 

[arnoldb]

A bit of an update...

I mentioned in my original post that this engine could do with a heavier flywheel, so I made one from a bit of 50x10mm HRS flat bar. It runs much better with this - I can even (with a big huff & puff) get it to run for about 10 turns on lung power. Some more running in on the compressor might just turn it into a breath-powered engine, but I don't think it will ever run very well on breath power, as there are quite a lot of "friction surfaces" involved.

Last weekend I didn't do anything in the shop, as I had a bit of flu, but during the week and today I made the new flywheel and a wooden base for it.
I have a router, but could not figure out a way to use it to contour the relatively small wood block... So I ended up with the rough block on the mill, and surfaced it with the flycutter (super-sharp honed cutting edge) and made the decorative sides with a routing bit chucked in the collet chuck - running the mill at maximum speed. Worked a treat ;D. I did not take any photos while doing this; I'll take some when I do a wooden base for a future project.

The new flywheel was also easy - I wanted it a bit more decorative, so drilled six holes in it, and while it was set up on the RT, just milled in the recesses on both sides:

The flywheel is small, so drilling it on the hub for a grub screw was not an option - I did the "grub screw and pin" to retain it; that required drilling a 2mm hole accurately through one of the spokes, and then part-way drilling 2.5mm to tap M3. To make sure I was going smack bang through the middle of a spoke, I used a 6mm drill and a bit of 6mm rod to make sure the spoke was aligned vertically:

So now the engine really is complete - except for a name plate ::

On to making that boring head...

Regards, Arnold

 

[SAM in LA]

Arnold,

Good looking engine and base. What kind of wood and finish did you use?

I don't think any of my engines would run on breath power unless you had lungs that were the size of trash cans. ;D

Regards,

SAM

 

[hobby]

Arnold,

That is a real, really nice engine,
You show very nice craftmanship in the machining of all your parts,
and the smoothness of how it runs, is exceptional..
and the display base shows good quality woodworking also..

 

[johnthomp]

wow onw weekend what a challenge ive roughed a couple of elmers engines together in a weekend but my favourite has to be elmers tiny i simplified the stand and cylinder to just square blocks due to not haveing a milling machine and altered the crankshaft valves to have an inlet valve and an outlet valve in the sme style so i didnt have to bore out the crankshaft i took it right up to 80psi on the compressor and it went like a bat out of hell sounded like a chainsaw at full throttle wich is roughly 9000rpm and with the way i did the valves it was not biast to wich way it ran just swap the air line to the exhaust port
but i still cant make an engine look as good as that yet well done fella thats an achievement and a half
congratulations
reguards john

 

[arnoldb]

Thanks Sam

The wood is "Rhodesian Teak" - an indigenous species in the far north-east corner of Namibia in the part bordering the old Rhodesia (now Zimbabwe).

As to the finish, well, it's just sanded smooth, and old-fashioned "hard" floor/furniture wax applied liberally (I use a wax called "Cobra Polish"). Then heated a bit for the wax to penetrate the wood, more wax added as it's soaked up, and later buffed down with a soft cloth to get some sheen. With age and more waxing, the sheen becomes more pronounced. I have a lot of teak furniture that has only ever seen this wax treatment - no oil or varnish; my dining room suite is as old as I am and have a mirror shine from the years of receiving this treatment - photo of the engine on said table, and the wax I use:

And the disclaimer - I use the wax pictured as it works for me as a satisfied customer and have done so for at least three generations of my family - not because of any affiliation to the manufacturers.

And, Yes, a bit of elbow grease is required

Hobby, thank you very much for the compliments

Thanks John ;D. Just stick at it; it becomes second nature to give a quick rub of parts over a bit of oiled emery paper to finish it off - especially to get a brushed finish like on this engine I built. Polishing it is another matter though; that takes time. :big: Tiny can sound like that if you tighten the spring up to take high pressure ;D - I have my little Tiny set with a feather-light spring pressure; 5 psi would blow the block off the port face. But set like this it's a treat to run on breath pressure alone ;D

Kind regards, Arnold

 

[johnthomp]

another engine ive built and ran to destruction was elmers standby that went really fast till the piston siezed solid in the cylinder and ripped the connecting fod off the crank mangleing the driveshaft in the bearing but was a belting little engine
and a little challenge i did was trying to built elmers slider engine but couldnt get the valves to seal properly so gave up on that but the open column with reverse went a treat i built that one for an elderly gent who built wooden rc boats and wanted to make a steam one he loved it
reguards john

 

[Hat56]

Speaking of Elmers engines I saw a two cylinder wobbler geared to a single shaft presented by Tubalcain on youtube and he suggested it was a number 115? made by Elmer. I would like to get the plans for this if anyone can help.

I have searched the John Tom to no avail.

Cheers Hat