Corliss Steam Engine (Coles Power Models)

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Yes exactly. I speak about exhaust valves and only the closing. For the opening, it's clear.
It's a big mystery for me. Perhaps the dashpots help? But in that case by depression or vacuum?
KVOM is correct. The dashpots are for quick shut off of the steam input valves. They have nothing to do with the exhaust. The exhaust is simple--it is simply rocked back and forth buy the eccentric train of rods, levers, wrist and more rods. It has nothing like the steam input which has a bunch of timing modifying mechanisms.

I'm wondering if you can send a photo with your concerns marked out, that might give us the understanding of what you are having trouble with. I can understand having trouble with the steam INPUT as that has all those modifying elements.
Here are the pictures of the assembling of the Corliss gears.
I have to say, it is totally beautiful and I am very jealous. Have you figured out how the exhaust works? Your wrist/exhaust mechanism shows it all. I like how you put brass bushings in the steam mechanism. did you build the knock-off mechanism oversize for that?
Very nice, keep posting updates on your engine. I would love to see pictures when you have it finished.
Hi Zapjack,

This is a picture of Agnes, looking at the valve gear !

Unfortunately due to Covid restrictions she is not in steam or viewable at the moment. Usually Agnes is running when the Markham museum is open.


I hope this picture is of help.
How big is Agnes? Any more photos?

Hi Richard, Guys,


Sorry I had assumed that people knew that Agnes is a full size dual cylinder Corliss steam engine !

This picture is looking towards the front of Agnes. The maroon painted front and the flywheel with the 20, I think, rope grooves is the big black thing in the middle of the picture. Just to give you some indication of size, the railings around the exhibits is 4 foot high.


This is a much closer view. The steam feed comes in just to my left near the top of the picture.


This is a picture of the barring engine. Used to turn Agnes over when starting her from cold or doing maintenance work on her.


This picture is of a model of Agnes positioned directly opposite with a modified valve actuation mechanism. Again like Agnes a dual cylinder machine with the steam coming into the high pressure cylinder.


Last but not least a picture of her front showing her pedigree.

Hope you like the pictures. I do have more, but these are the interesting ones.
Here's the governor body. The cubic parts is completely from bar stock and the 3 tread are machined
View attachment 125017View attachment 125018View attachment 125019
Any more on this build? Are you close to it running? I thimpfk the governor is the most difficult section of everything.

I noticed that you mentioned the "Greene" earlier, is that the "Improved Greene Steam Engine"? I am looking for plans on that, and castings if anybody makes them. Do you know of any plans?
Hey Zap. We haven't heard from you. Is your cat alright? Have you made progress on the governor to your Coles/Ray? I am having a bit of trouble on how the "safety latch" works. I don't see anything that it actually does. Does it actually protect something? Also, I cannot understand how the actual little latch is suppose to be placed inside the housing. Do you have a photo of that?
Hello everybody,
I will retire at the end of April '23.
But, I'm going to move to the south of France in Nice Côte d'Azur. But it's 715 miles from home. (1150Km)
And every month, I move a full LT of goods, furnitures, workshop, etc...
It's very hard to move and at the same time do my job of technical manager in one of the biggest Belgian Trucks Cy.
At the end, it's a lot of job. So, be patient, I will be back soon.
Attached file, my future workshop in progress