Steam engine (Tiny horizontal double acting, maybe with reverse)

[gbritnell]

I made the top and bottom lever collars. I cut a .012 slot in them and they were drilled .020. The gears are pressed onto the .032 stainless shafts so when I tried to assemble them I realized that I couldn't slide the top one past the horizontal one. What to do? I wasn't happy with the thickness of the upper flange because it didn't give the shaft enough support so to kill 2 birds with one stone I opened up the hole from .032 to .055 and made a longer brass bushing. This allowed the shaft with the gear to clear the horizontal one and once in place I slid the bushing down into the upper flange.

[gbritnell]

The next project was to make the ball levers. I tried a couple of different approaches because with the small size and multiple machining steps I kept breaking them. I ended up doing them this way.
I first turned a piece of .187 brass round to .100 (ball size) I then reduced the diameter to .043 leaving .100 for the ball on the end. With files and emery I formed the ball on the end of the shaft. I then buffed it while it had support.
From there it went to the mill and the dividing head. I trued the stock up with an indicator and found center. I then cut 2 flats with a .062 end mill leaving the web .015 thick. The 2 lever holes were drilled with a .015 drill. They end up at .020 but when I had drilled them larger in previous tries the stock would break when I put it back into the lathe to reduce the shaft size.
Once back in the lathe the shaft was cut to .03 diameter and the rear flat was filed by hand down to .012 thick.  The piece was then nipped off and the final filing was completed.

[gbritnell]

The final 3 pictures show the ball arms assembled onto the vertical shaft. I made 2 pins at .020 diameter with a slight area at .021 so that when I put them through the holes they would bind in place.
I had to slip the flywheel back on for the last picture just to show the proportions of the governor. At first I thought it was going to look too large but with the flywheel for a comparison it doesn't look too bad. Next up will be the connecting links, the throttle valve and the levers and link to operate it.
gbritnell

[Jo]

  Wonderful   

I have decide that it is time I gave up making governors.

Jo

[Bezalel]

George


I really enjoy your work, thanks, Please keep 'em coming,


I just wonder how many super macro photos you have to take of your bench top to ensure you get a couple of pictures with an engine in frame. 

Your're an inspiration to so many of us   

Bez

[fcheslop]

Truly inspiring work 
I'm selling up and joining Don on the Electrical work
Thanks for posting
kind regards

[Don1966]

Awesome George, I am running out of words here. You are the best, I just love it. Keep those photos coming.

Don

[b.lindsey]

Well I'm out of superlatives for sure!!  I too would be interested in seeing the set-up for cutting the gears though and the cutter as well!!  Thanks George for keeping us all mesmerized!!

Bill

[ScroungerLee]

Very nice George.  I love tiny things like that, but as you say it takes creativity to avoid breaking too many teensy parts.  I appreciate your sharing your methods.

Lee

[gbritnell]

Thank everyone for the comments,
Bill, attached are some pictures of the gear cutter and the cutting. I made a spur gear so it would be a little easier to see  Whenever I cut a gear I leave a pointed nub on the blank. If the blank has a hole in it I preset with a piece of shaft with the nub. I have tried setting with a surface gauge but at these small sizes I just can't get in to see what I'm doing. With the nub I can line up the centerline of the cutter to the nub with a magnifying glass. The cutter is drill rod. As I had mentioned I layed out the profile of the tooth and turned the cutter blank to the top width of the tooth. I then cut the side angle to give me the approximate width at the bottom of the tooth  The cutting was like any other gear, touch the cutter to the stock and dial in the whole depth of the tooth. I put marker ink on the end to help show the teeth. I also took another shot with the stock laying on my scale to show the size.
gbritnell

[zeeprogrammer]

Thanks for posting those pics and the explanation. Very helpful. Very daunting 

[ScroungerLee]

Ahh now I see how you did the cutter, I was being a little dense in the head

Thanks,
Lee

[gbritnell]

This is today's update on the state of the governor. The vinyl tubing I was going to use didn't work out. It went together fine and held fast when I stretched it over the pulleys but as soon as it got the slightest touch of oil it slipped. Now what do I do? I started going through boxes, shelves and drawers trying to find something that would work. Nothing! I have 5 of those home building center 5 gallon buckets that I keep for material, mild steel, stainless steel, sheet steel, plastics and gasket material. As I was searching I found an old wallet that I had thrown in with the gasket papers for some future leather need. Well belting is made from leather maybe I'll give it a try. My pulley grooves are .032 wide and this leather is around .040ish. I cut of a strip and clamped it to my cutting pad. I then clamped a metal strip as a cutting guide and tried for .035-.040. It came out pretty darn close. Using the vinyl belt as a guide I cut and super glued the leather together. I let it dry and then kind of puckered up when I had to stretch it over the pulley flanges but it held. A little compressed air to spin the engine over and the balls flew out just like they were supposed to. I ran it for about 2 minutes and the belt kept working. I don't know how long it will be good for but for now I have no other ideas.
I also got the throttle valve and a piece of the linkage finished.
Anyway, enough of the idle chatter. Here's some pictures for today.
gbritnell

[zeeprogrammer]

Nice George! That last shot with the penny is a real attention grabber. Amazing.

I like the leather idea. I think I have to go the same way for Spinster.

[b.lindsey]

Thanks for the gear cutting pics George and the latest update is just mind boggling too!!!

Bill