Restrainting pin question

[Tom Line]

Originally Posted by Jeffy

Our team this year wants to use a pneumatic clyinder as a restraining pin for our spring loaded kicker. My question is whether or not we can directly use the piston rod as the pin. I know it follows the rules, but would using the piston as the pin damage it?

Absolutely it will damage the shaft. Though most people don't realize it, metal isn't "hard". It's actually quite soft. Any time you see metal on metal interaction, for instance in the form of a pin, or a long shaft, etc, it's probably been hardened.

Machine a sacrificial pin that threads onto your shaft, and make sure that pin is supported against side loads by traveling through a hole in a plate. That way when you destroy that pin (and you will!), you can replace it and keep on rockin'.