Engine from Jan. 1953 Popular Science.

[davewaldo]

This is a lovely build. Very inspiring for a new guy Thanks for posting so many photos!

Dave.

 

[GaryK]

Here are the piston and their rods. I made them a while ago so I'm just throwing them in here. I will be making some Teflon rings for them.

Now for the eccentrics. I start off turning some grooves in some 3/4" for the rib I made in the straps. Then I cut them off a little long.

Then since two of them were only 3/16" thick, I used a stop in my collet. I turned the surface of the stop square. Then I turned the part to thickness. two pieces to 3/16" and two to 3/8".

Here is a test fit.

Then a test fit for all of them. The reason I split them into pieces is that I have no idea how different the placement will be for forward and reverse. I will first get it running in just one direction and mark the location. Then the other direction. Once I know the location for both then I will pin and screw both pieces together.

The I drilled the 5/16" hole in all the pieces.

Then for the 3/8" thick parts I made a fixture to turn the hub for the screw to lock it to the shaft. This is another departure from the plans.

Here is the first one turned.

The next two pictures show the completed parts with 2 being mocked up.

Only a couple of parts left!

I think I have only have the flywheel, glands, Input air piping, piston rings and the valve spools.

Next I think I'll make the valve spools.

Gary

PS and the reversing gear linkage parts.

 

[GaryK]

Two parts this time. First is the gland.

These were so small I knew I wouldn't be able to get much thread so close to the shoulder so I took a different approach. Since they weren't actually doing any actual hard work I figured I would make them two piece.

I started with a piece of bar stock and cut the hex on my mill.

Then I drilled and reamed a hole. Next I threaded a length of material, turned down a length of it to press fit the nut I made.

Then I just pressed them together. (Yea, I know I should have blown the chips away before taking the picture)

Turned out pretty good.

The next part was the valve spools. Not much unique here here so I won't show the machining process.

Since I was adding a reversing gear to this engine I wasn't sure exactly how long the parts would end up so I made the in two pieces also. The slotted part was made long and then cut down to the correct size after testing the assembly in the engine.

The part isn't complete. I still have to machine flats on the slotted ends.

Here you can see the entire assemble. I think it turned out pretty good.

Next will be the rest of the reverse gear linkages.

Gary

 

[GaryK]

Now on to the reversing linkage.

For some reason round bar stock seems a lot cheaper that rectangular so I start with that to make some square stock.

Then while it's square I drill the holes

Then using a point I center the hole on the rotary table. I press it into the hole and then tighten the clamps. Not 100% perfect but way more accurate than I need for this part.

Then I cut the ends of the parts.

Here are one set of parts with the ends all rounded.

Then while I still have two straight edges I remove the material in the middle.

The the other part.

That's it for now. Next time I'lll complete these parts.

Gary

 

[GaryK]

Here's the completion of the reversing gear linkage

Using pins whose diameter I calculated to give me the proper taper, I cut the parts to width.

The other links are just straight cuts.

Then I cut down the ends to the proper height.

Then the same for the other link. Notice the drill bit used as a spacer. This will assure that the cut will be perfectly centered. Overkill but I did it anyway.

And here are the parts for a complete set of linkages.

Lastly a mockup of how they will fit into the engine.

The flywheel, input air piping, and piston rings are all that's left. Getting close!

Gary

 

[drysdam]

I'm afraid I didn't get the bit about the drill bit used as a spacer. I couldn't tell what it was spacing or what it was supposed be centering.

 

[tarawa]

Fantastic workmanship. I don't think my eyes are good enough for this precision work!

 

[GaryK]

I'm afraid I didn't get the bit about the drill bit used as a spacer. I couldn't tell what it was spacing or what it was supposed be centering.

The purpose of the spacer is this. Suppose my part is 1" thick. I want to remove 1/8" from each side.

I cut the first 1/8" from one side. Now I could either re-adjust the depth of cut another 1/8" deeper and cut the opposite side.

Or I could add a 1/8" spacer and set the part on it. This will make up for the material I cut off during the first cut. Then I won't have to re-adjust the depth of the cut. It will also assure the cut is equal on both sides.

Either way will work, but I think the spacer was faster.

Gary

 

[aarggh]

I'm glad you explained the spacer bit there Gary, as I was trying to work that out myself. Great idea. and very, very nice work mate!

cheers, Ian

 

[ChooChooMike]

Love all the pictures, especially all the little fixtures for the doodad parts !! Very clever setups !! KISS principle here for sure

Mike

 

[drysdam]

Or I could add a 1/8" spacer and set the part on it. This will make up for the material I cut off during the first cut. Then I won't have to re-adjust the depth of the cut. It will also assure the cut is equal on both sides.

Aha, great idea! And I wouldn't ever have even understood this solution if I hadn't the problem myself. The more I learn, the more I realize that I'm just expanding my frontier of ignorance and need to iterate over the entire thing again to push it out farther.

 

[charlesfitton]

I'm enjoying this whole article - It just make me feel bad that I'm not in the basement wrecking things myself...

 

[drysdam]

Heh, I just now came up from the basement. Working on a magic trick by request of my son. I'm close to finishing, but if I keep working I'll have to start over. I'm sure you know what that's like.

 

[GaryK]

I don't know why, but I wasn't looking forward to making this part, but It turned out pretty easy.

This picture is a little out of sequence since I didn't show if being made on the lathe. (actually I forgot to take a picture). Anyway just turned the part and removed the bar and mounted it in the mill to drill the cross hole. Still being attached to the bar just made it easier.

Then I put it back in the lathe and cut it off.

Then here they are, the lathe work completed. I actually made three of them but screw up and drilled the second part all the way through instead of almost the way.

Then I drilled the air passage hole through to the cross hole.

Then to make sure the cross hole was aligned with the mounting holes I inserted the brass tubing and clamped it parallel to the jaws.

I used a couple of parallels as spacers so I wouldn't drill in to the vise. Then drilled the mounting holes.

Next I mounted everything to the cylinder block so everything would be in the correct position.

Then I used plain old plumbers solder to permanently attach them.

After it cooled down it was back to the mill to drill the air passage through the tubing.

All done. Just need to clean it up some more.

Getting real close here.

The flywheel is next.

Gary

 

[GaryK]

Not much to making a flywheel.

First I cut a pocket in one side. (I forgot the picture. I was actually holding the part on the OD in the chuck.)

This allows me to hold it on the ID to turn the diameter and face the other side.

Then cut the pocket (for lack of a better term) in the other side.

Then drill the center hole.

Then on to the mill for the set screw hole. I had to use my extra long center drill for this.

And then the completed flywheel.

Last thing to make are the Teflon piston rings.

Gary

 

[GaryK]

Now for the last part. The piston rings.

Teflon is a good material for this job. They can stand the temperatures if I were to use steam and not just air to run this engine. Easy to machine and available.

All I has was some sheet stock so I started with that.

I had to use a Forstner bit to rough out a hole to start with. I clamped it between two pieces of wood to hold it in place.

I ended up with my two blanks.

There's just enough material there to allow me to clamp it in the vise to bore the center hole to size.

Then I made a jig to turn the outside on the lathe.

Then to finish them off I used a razor blade to make a diagonal cut to allow me to fit them on to the pistons.

Well all the parts are done for now. I do have to figure out a lever to switch the reversing gear but I will save that for the end.

Now I will be putting a lot of time in at the bench cleaning everything up and fine fitting all the parts into a working machine.

I may post some of it if it is interesting enough.

Gary

 

[aarggh]

If you had one of the retaining edges not so proud of the groove, could you heat the nylon and slip it over then? The nylon ring on my nailgun recently failed, and looking at the replacement, it was smaller than the OD of the piston, so after hunting on Google found it was recommended to stick it for a couple minutes in boiling water, and then it should slip over and after a while settle back to it's nominal size. I haven't gotten around to it yet though so don't know foolproof that is. but it is what the manufacturer recommends anyway.

cheers, Ian

 

[GaryK]

If you had one of the retaining edges not so proud of the groove, could you heat the nylon and slip it over then? The nylon ring on my nailgun recently failed, and looking at the replacement, it was smaller than the OD of the piston, so after hunting on Google found it was recommended to stick it for a couple minutes in boiling water, and then it should slip over and after a while settle back to it's nominal size. I haven't gotten around to it yet though so don't know foolproof that is. but it is what the manufacturer recommends anyway.

cheers, Ian

That might work with nylon, but Teflon is a lot more temperature tolerant. The temperature of steam won't affect it so boiling it won't. Cast iron rings have a gap so I really don't think it will have much difference.

Gary

 

[Rutje]

Nice work Gary,

Half year ago i build the same machine. I keep it as close as possible as the drawing because it is my first steammachine.

[ame]http://www.youtube.com/watch?v=OAMRjQgSL4o&feature=player_embedded[/ame]

Timo

 

[jwcnc1911]

Looking fantastic! I love what you did to get an extra thread on that nut in post 43. I've done this several times when the total depth of thread will literally only allow for a thread or two. Your killing me how close you work to your vise jaws by the way! Make you some soft jaws man!