Author Topic: PMR 7 Twin Cylinder Steam Engine  (Read 20824 times)

Offline zeeprogrammer

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Re: PMR 7 Twin Cylinder Steam Engine
« Reply #315 on: May 04, 2018, 10:26:59 PM »
Thanks Peter. For the novice I would suggest something simpler. Certainly a single cylinder. A casting might be okay but it too would need to be pretty simple.

Thanks bent. I did try removing the gland nut but saw little difference. I'm pretty sure it's the head cover. I remember having had trouble with a center drill on one of the covers and when I look at that one... :thinking:. When I get the gumption up, I'm going to try remaking it. Although it's a cast part, only about 1/16" of the rim shows so I think some bar stock will do.

No doubt a lot of adjustment is needed as well. I get a lot of air out of one cylinder's exhaust but not so much out of the other. After twiddling with the eccentric, I got better exhaust. But I don't think the valves are in the right place.

On the plus side, what I thought was wobble in the flywheel turns out to be the crankshaft shifting a tad left and right. I should be able to adjust that with the cranks. The flywheel itself looks pretty true.
Carl (aka Zee) Will sometimes respond to 'hey' but never 'hey you'.
"To work. To work."
Zee-Another Thread Trasher.

Online b.lindsey

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Re: PMR 7 Twin Cylinder Steam Engine
« Reply #316 on: May 05, 2018, 12:30:15 AM »
Keep after it Zee till you are satisfied with it. There is as much to be learned from that as there is in machining the parts and ultimately more satisfaction as well.

Bill

Offline gary.a.ayres

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Re: PMR 7 Twin Cylinder Steam Engine
« Reply #317 on: August 21, 2018, 12:01:32 AM »
Hi Carl -

Have really enjoyed this build log, in terms of both the build itself and the discussion around it.

Particularly interesting to me as a complete novice. Despite not yet having built any engines at all, I impulse bought a PMR #6 kit a while back, but I am no way going anywhere near it until I have have made a few fabricated engines, starting with a simple single acting oscillator.

Congratulations to you on a successful build, even if the success was not absolute (it never is...).

 :cheers:

gary


Offline zeeprogrammer

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Re: PMR 7 Twin Cylinder Steam Engine
« Reply #318 on: August 21, 2018, 12:17:12 AM »
Congratulations to you on a successful build, even if the success was not absolute (it never is...).

Thanks Gary. As a stationary...it looks pretty good. But it's not a runner. However, I'm fairly pleased with the learnings I got out of it. I'm particularly pleased with the flywheel.

"it never is..." such a truism. I do things that my friends/relatives think are awesome...but being close to the work...I see the boo-boos.

When it comes to what we do...we are our worse critics. Not a bad thing.
Carl (aka Zee) Will sometimes respond to 'hey' but never 'hey you'.
"To work. To work."
Zee-Another Thread Trasher.

Offline gary.a.ayres

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Re: PMR 7 Twin Cylinder Steam Engine
« Reply #319 on: August 21, 2018, 09:02:59 AM »
Quote
When it comes to what we do...we are our worse critics. Not a bad thing.

Agree, as long as we don't make ourselves miserable by failing to notice the good bits - a trap which you clearly have not fallen into.

Quote
..it looks pretty good. But it's not a runner.

At my level of knowledge I must defer to you on that. It does run though  :)

Cheers,

gary