where to find air cylinder cushions

[territorialmillworks]

Want to put either an elastomeric or spring on the air cylinder to keep it from hitting at TDC. Having problem sourcing these because 1) don't know the right terminology, 2) don't know the right spring/durometer rate 3)never bought anything like this. Have 75# ram with 2" X 10" cylinder with 1" shaft. And yes, I will eventually get the pneumatics worked out but don't want to damage things in the meantime.....THK

[monstermetal]

Want to put either an elastomeric or spring on the air cylinder to keep it from hitting at TDC. Having problem sourcing these because 1) don't know the right terminology, 2) don't know the right spring/durometer rate 3)never bought anything like this. Have 75# ram with 2" X 10" cylinder with 1" shaft. And yes, I will eventually get the pneumatics worked out but don't want to damage things in the meantime.....THK

This is kind of a junk yard answer but what as been bouncing around in my head is using a pair of urethane body bushings

They are pretty cheap and would be easy to replace Bushing link

You can have custom urethane bumpers cast but I think for the dollars these would work swell...

[BIGGUNDOCTOR]

If you put the cushion inside the cylinder make sure you leave some space for the urethane to expand sideways. I have used tubular urethane on stamping die sets. It comes in various Durometers (hardness).

The cushioned air cylinders I have worked with used air to do the cushioning. Usually had a needle valve to adjust the dampening effect. Google Bimba air cylinders, and look to see if they have a cutaway of one of the cushioned cylinders.

[John Larson]

The 2" cylinder with a 1" rod is not likely to provide you with enough area on the rod side of the piston to give good behavior, unless you run differential pressures, however I mention this only because you might consider acquiring a bigger cylinder with an air cushion built in by the manufacturer. In the meantime, you might try an inexpensive approach that should work, namely, a rubber cushion from a leaf-spring truck that keeps the suspension from bottoming out. If the hammer head hits it at least 1/2" before the cylinder tops out, and it is anchored to the hammer frame, you should have no damage. Good luck.

[empireweld]

Try acrotech www.acrotechinc.com/

[territorialmillworks]

Found a short piece of round polyurethane 90A on ebay that I can turn on the lathe. THX for the ideas..........

[BIGGUNDOCTOR]

Use a HSS tool bit with a good amount of rake that is ground as smooth as you can get it. What worked for me was pushing the urethane over a tight fitting mandrel, then cutting it.