My take on PM Research #1 engine

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Finally the moment of truth has arrived. Will the engine run or it will be a dud?

And it runs. But not without considerable effort from my side.

Here is the link


I tried to run it but noticed air leaking out of exhaust port continuously.
The slide valve was lapped into the steam chest. Using 180, 220, 400, 800 grit and finally using a metal polish.
Even after this the engine refused to run.
Valve timings were checked and changed repeatedly but there was no success. All the leaks were chased and rectified.
I was using a tyre inflater as a compressor to run the engine. The pressure was going above 5 bars but the engine refused to start.
Then I noticed that the piston end clearance is only about 0.2 mm at both ends. There was no space for air to come inside the cylinder.
So I had to modify the end covers to allow the air to enter the cylinder. For this I filled out some portion of the boss near the steam passages.
And after some more valve timings adjustment Success.
IMG_20210826_193342.jpg



Regards
Nikhil
 
Nikhil,
Very nice job, and I can tell there are lots and lots of hours in that beautiful project. You talk so casually about that block of teak and replacing it with plywood (am I correct on that?). Here in the US, teak from India is ranked up with American Walnut, and replacing it with plywood would almost be a sin. I am only joking, but only a little bit. And maybe some paint colors that say "look at me!" Again, only kind of joking.

Working with castings is both a blessing and a curse and I can see that you spent a lot of time getting the set-ups right for the first cuts. Given that you had only one chance to get it right, I would call your job ..... perfect! Impressive.
Thanks for sharing your project with us.
Lloyd
 
Nikhil,
Very nice job, and I can tell there are lots and lots of hours in that beautiful project. You talk so casually about that block of teak and replacing it with plywood (am I correct on that?). Here in the US, teak from India is ranked up with American Walnut, and replacing it with plywood would almost be a sin. I am only joking, but only a little bit. And maybe some paint colors that say "look at me!" Again, only kind of joking.

Working with castings is both a blessing and a curse and I can see that you spent a lot of time getting the set-ups right for the first cuts. Given that you had only one chance to get it right, I would call your job ..... perfect! Impressive.
Thanks for sharing your project with us.
Lloyd
Hi Lloyd,

Thanks for the encouraging words. I am a novice and still learning.

As for the teak it is Burma teak. It is imported from Burma or Myanmar. I wish to get it carved out into one of our Gods or Goddess. So I will be replacing it with a plywood box.

Regards
Nikhil
 
Hi Lloyd,

Thanks for the encouraging words. I am a novice and still learning.

As for the teak it is Burma teak. It is imported from Burma or Myanmar. I wish to get it carved out into one of our Gods or Goddess. So I will be replacing it with a plywood box.

Regards
Nikhil
That will be a very fitting use for the teak!
 
Newbie question, asked out of general curiousity:

I've seen the Blondiehacks hacks video of building this engine, and now the build logs here. In all of them, to machine the base surfaces where the main bearings attach, the bed has been secured in the mill at an angle, usually requiring a complicated fixture.

If one were using a mill with a head that could tilt side-by-side, like a Bridgeport, would it make more sense to secure the base flat on the table and tilt the head? I'm assuming the angle-fixturing techniques are being used because these mills don't have the ability to tilt the spindle, or is there a reason to not tilt it that I'm unaware of?
 
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Quinn did a great job on her PM research steam engine, but check out Joe Pie's video series building the same engine. His fixturing of the base is very elegant, straight forward and not at all complicated.

Joe also has the luxury of larger equipment, so many of his methods aren't directly transferable to smaller bench top machines, but they still inspire us. He also somehow manages to single-point 2-56 threads! I have also not seen him resort to tilting the head on his Mill. Quinn's builds help me both understand some of the limitations of my equipment, while seeing some work-arounds. Both Joe's & Quinn's videos usually get filed in my "Work Holding" folder on YouTube.

Given the significantly better rigidity of a fixed column on the LMS Mini Mills, and seeing what Quinn & Joe achieve with their setups, I think that you can get more rigidity & stability by tilting the part rather than the head.
 
Yes, Quinn does a good job of doing setups on the small lathe and small mill..
 
Newbie question, asked out of general curiousity:

I've seen the Blondiehacks hacks video of building this engine, and now the build logs here. In all of them, to machine the base surfaces where the main bearings attach, the bed has been secured in the mill at an angle, usually requiring a complicated fixture.

If one were using a mill with a head that could tilt side-by-side, like a Bridgeport, would it make more sense to secure the base flat on the table and tilt the head? I'm assuming the angle-fixturing techniques are being used because these mills don't have the ability to tilt the spindle, or is there a reason to not tilt it that I'm unaware of?

Jgalak, Where the bearing cap sits, there is a small recess of about .03" that helps locate the bearing cap, (and Quinn forgot to machine that recess if I remember correctly?) If you use the "tilt the head method", you asked, the recess would be difficult to execute,
 
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