Making cast iron piston rings

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As Norman says most small engines do not have rings or have labyrinth seals but with double acting steam engines the piston is very thin when compared to an IC engine and some form of ring or seal is necessary.
I am building Gauge 1 (1/32nd scale) British pattern locomotives with 1/2" bore steam cylinders.
I have used traditional graphited yarn and modern O'rings but am not completely happy with either.
The former is fiddly to apply and the latter suffers from stick-slip , ie. when stationary the O'rings grip the cylider walls rather tightly , often requiring a push to overcome this.
I have been experimenting with cast iron rings and have had some success even though the rings are so delicate that breakage is common.
I am sure Norman and the older members will have come across Cords piston rings .
These were/are? made of spring steel and were very thin, three rings would fit into a piston groove , the gaps being staggered at 120 deg to each other.
This configuration allowed a good seal to be restored to a bore that had worn oval.
So has anyone tried to make rings of this type ? I will try the idea out when I can find the time.
Dan.
 
Thank you Dan( Abby)) I as a stopgap solution to a worn ( out) 997cc Morris 1963 Mini Cooper, I did fit Cords Rings. I was watching the over 50 year original and British version of the Italian Job where the best advertising of Mini can still be found. Oddly, my son who is still into such things reminded me that Mini Coopers are changing hands at £20,000 whereas I paid a mere( now) £565 for mine.
As you say, Dan, Cords rings were fitted but am I correct in saying that the the worn ring channels in the pistons were re-cut and 'expanded?

I regret that it is such a long time ago that my memory may be confusing a further 'modification' involved over boring +60 thous scrap engine block- which cost me £10.
I can recall peening the conrods and worrying about the double springs on the re-worked 12G295 cylinder head( ex a later Mini Cooper of v998cc as opposed to my 997 version- with the long throw crankshaft.

You see I moved to dealing with my wife's Mk111 Triumph Spitfire which had SU carbs that were always going out of tune.
Really digressing, I recalled trying to buy a Seat600 which was a 'sort car version' with no roof or doors and black wickerwork seats. It was in Menorca where I had a house( for £7500) and I was goingb to take it home as a 'Noddy Car' project for my son and then my daughter. It would have gone home with a donor scrapper but sadly, it is all buried in a local football field on the island.
The Best laid schemmes of mice and men gan aft tae glae.

All that is left now is -- a model Min Cooper and a promise of van eye injection in the New Year.

I hope that the New Year brings something better for all of us
 
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