Corliss Steam Engine (Coles Power Models)

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I continue with the small parts of the regulator.
It's difficult to talk about "machining sequence" because there is a lot of handling, changing tools and/or machines. On the other hand, there are certainly several ways to arrive safely....
The two 3/4" balls are bearing balls previously de-tempered. After drilling and tapping I had to re-polish them because the heating blackened them + a fine crust on the surface.
The weight, on the other hand, was taken from bar-stock and machined with the Schaublin spherical turning device. Luckily, I "only" have an error of 0.05mm on the diameter.
LeZap
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I continue with the small parts of the regulator.
It's difficult to talk about "machining sequence" because there is a lot of handling, changing tools and/or machines. On the other hand, there are certainly several ways to arrive safely....
The two 3/4" balls are bearing balls previously de-tempered. After drilling and tapping I had to re-polish them because the heating blackened them + a fine crust on the surface.
The weight, on the other hand, was taken from bar-stock and machined with the Schaublin spherical turning device. Luckily, I "only" have an error of 0.05mm on the diameter.
LeZap View attachment 151835
without a doubt, the governor, as we would call the 'regulator', is the most complex and difficult section of the Corliss.
 
The job of the week is the damping cylinder of the governor.
Small note regarding the thread, which should have been 7/16" in 36TPI which I converted to M11x70.
also look at the thread output obtained with the help of a micrometric stop (a comparator in fact)
I still have to break in the parts, but it will be during assembly
LeZap
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The job of the week is the damping cylinder of the governor.
Small note regarding the thread, which should have been 7/16" in 36TPI which I converted to M11x70.
also look at the thread output obtained with the help of a micrometric stop (a comparator in fact)
I still have to break in the parts, but it will be during assembly
LeZapView attachment 152125View attachment 152126
I was showing mine to a friend. It was aa bit rough in operation. I had used brass as the piston. He said to change it to bronze. I might do that. How smooth is yours? I notice you have a bolt head on yours. I put a thread in mine and screwed the piston shaft in.
 
Yes, I prefer bronze.
Just a question, witch quality of oil need this damping cylinder?
LeZap
 
Yes, I prefer bronze.
Just a question, witch quality of oil need this damping cylinder?
LeZap
I don't know what quality of oil to use. What makes me wonder about it's construction is that it's purpose, apparently, is to dampen the action of the twirling balls, not too quick to speed up and not too quick to slow down. But the piston has four small cutouts in the four corners which would allow the piston to work with little to no friction, so it must need rather thick oil.
 
Here are the parts of the safety latch. Honestly, I have no idea what this latch is for.
Both are cut from solid, the latch is 10mm high and all filed by hand, it is 😭🤬😓👎 to be machined!
L.Z.
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Here are the parts of the safety latch. Honestly, I have no idea what this latch is for.
Both are cut from solid, the latch is 10mm high and all filed by hand, it is 😭🤬😓👎 to be machined!
L.Z.View attachment 152156View attachment 152157
I have asked the ssame question and tried my darndest to figure out how it works and what exactly is it's purpose.
 
I think some or perhaps many steam engine governors were designed to fail in a position that closed the steam valve, ie: if the belt that drives the governor broke, you would not want the engine to run away in speed.

I know what the latches do on a Corliss, but I have not heard the term "safety latch".

Edit:
Our member Joe Prindle mentions on another site that the safety latch was as I suspected, to prevent overspeeding the engine if the governor belt broke.
Joe said that the flywheels on the old Corliss engines could be 12 feet or more in diameter, which made it prone to exploding if it were rotated at an excessive rpm (an excessive rpm could be something over 100 rpm would be my guess).

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I think some or perhaps many steam engine governors were designed to fail in a position that closed the steam valve, ie: if the belt that drives the governor broke, you would not want the engine to run away in speed.

I know what the latches do on a Corliss, but I have not heard the term "safety latch".

Edit:
Our member Joe Prindle mentions on another site that the safety latch was as I suspected, to prevent overspeeding the engine if the governor belt broke.
Joe said that the flywheels on the old Corliss engines could be 12 feet or more in diameter, which made it prone to exploding if it were rotated at an excessive rpm (an excessive rpm could be something over 100 rpm would be my guess).

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Well, that probably gives it's purpose, but still I will have to study it some more to figure out how it works. I can't even figure out how that little curved finger fits in it's housing.
 
On the milling machine, what I will call "stupid-assembly" (not to be done!!!)
All safety and stops have been dismantled. Fixing at a minimum and even the crank has been disengaged. I turned the frame by hand. Fortunately, precision is not important. It's just cosmetic. The Zap
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I think it is there for when you set the trips on the intake valves during timing
OK, but what trips this safety trip? I see nothing that can trip it. Is there something the original, AW Ray, missed? I thimpfks maybe he died before he managed to complete it. After all, it was 1946 and we know virtually nothing about him (and Eloda too.)
 
A post online by Jim Mackessey, who restored a Rice & Sargent Corliss, 2005:


Many patents were taken out on devices to prevent overspeeding if the governor belt broke. Without them, the probability of an accident was pretty high. We have a Rice & Sargent Corliss engine at our museum, and one of the patented features is an inertia device on the crosshead consisting of a pendulum held forward by a strong spring. It is cast hollow so it can be filled with shot to make it heavier. If the engine goes too fast, the weight of the pendulum overcomes the spring when the engine reverses stroke and strikes a bar that
knocks the governor off a cam and shuts the valves down. Other makers used other devices, some of which were pretty clever. Our engine has a 7-1/2 ton flywheel, 11 feet in diameter. This ran at 150 RPM, and that's scary enough. I wouldn't want to be anywheres near it if it ran away!-JM



Here is Jim's Corliss during trials.
This engine was buried in a factory that was being demolished, and very narrowly avoided getting sent to the scrap yard.


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The instructions on my Corliss …no it a coles ..said to block the govenor up 3/8 inch and set the trips on the valve to drop just past dead centre…yours is built in to the governor I think
 
Now I'm starting the steam inlet valve, the plans for which are ataached.
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It is a secondary part which is not involved in the good functioning of the engine. However, and given my somewhat perfectionist side, I will do everything I can to create the piece as faithfully as possible. I will post the progress step by step.
I start with a solid 30mm stainless steel bar. I took it in a chuck with 4 independent jaws, first to have perfect centering, then because the jaws are longer than on a standard 3 jaw. I first made two cuts corresponding to the lower part of the roundings. The spherical part was used very well in 4 steps and as many changes in tool position. But the connections are very well.
LeZap
 
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