Sizing Piston Rings

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318J
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Re: Sizing Piston Rings

Post by 318J »

Bob D. wrote: Fri Jul 29, 2022 8:25 pm With the cylinders freshly bored I question why there is several thou variations in the bore…. Have they been honed?
You must have misread what I said, it's not several thousands, about a thou to a thou and a half at best. Everything is nice, round, and true. Maybe I'm overthinking the effect that minute of a change will have.
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Bob D.
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Re: Sizing Piston Rings

Post by Bob D. »

Bill Shields wrote: Fri Jul 29, 2022 9:09 pm They are good, but as you say, cost of setup exceeds cost of individual rings.

A dozen rings probably will not cost more than 4.

In reality, step cut are nice, but not needed for our application.
Your most correct Bill. That link was for my stoker rings. You don't need step rings for our tea kettles. They make other styles too. The setup fee was more than the cost of the four 5-1/16” rings.q
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hoppercar
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Re: Sizing Piston Rings

Post by hoppercar »

Has anyone ever found a good way to expand cast iron rings, and get them on the piston without breaking them ?......the solution to that problem still eludes me ?
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Bill Shields
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Re: Sizing Piston Rings

Post by Bill Shields »

I use stack up pistons to avoid that problem.
Too many things going on to bother listing them.
hoppercar
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Re: Sizing Piston Rings

Post by hoppercar »

Yeah, that's what I did too with my last locomotive, I stacked up both the pistons, and the piston valves....seems to be the best solution ?....I just can't spread open iron rings with out deforming them, or breaking them......then it ziinggss across the shop, into some deep dark, unexplored cavern that's guarded by Medusa, never to be seen again...
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NP317
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Re: Sizing Piston Rings

Post by NP317 »

Same here:
Built up pistons and valves, with "captured" rings upon assembly.
RussN
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