ballen
Diamond
- Joined
- Sep 25, 2011
- Location
- Garbsen, Germany
This photo shows the piston that drives the long axis of my J&S 540 surface grinder. I pulled it out because it felt sticky.
If you look carefully at the photo, you can see why the piston felt "draggy". The piston is ground and hardened with two grooves. The grooves carry split rings, also hardened and ground. The rings are meant to "float": rotate and slide freely in the grooves. The left-hand ring is OK. The problem is that the right-hand ring is stuck in its groove. Easily fixed with some judicious stoning and fitting.
A few minutes with Google shows that these rings are called "wear rings" and are often made from PTFE or other slippery plastic.
What's the function of these rings? Does it make sense to keep the existing ones (after they are both free to float)? Or can/should I replace them with modern plastic ones?
If you look carefully at the photo, you can see why the piston felt "draggy". The piston is ground and hardened with two grooves. The grooves carry split rings, also hardened and ground. The rings are meant to "float": rotate and slide freely in the grooves. The left-hand ring is OK. The problem is that the right-hand ring is stuck in its groove. Easily fixed with some judicious stoning and fitting.
A few minutes with Google shows that these rings are called "wear rings" and are often made from PTFE or other slippery plastic.
What's the function of these rings? Does it make sense to keep the existing ones (after they are both free to float)? Or can/should I replace them with modern plastic ones?