Bungy and Surgical tubing

[Ether]

Originally Posted by Mike Betts

Even with pre-charged cylinders at some percentage extension to maximize speed and direct exhaust at .3 cv, I'm having a difficult time getting a dangerous material fatigue scenario for an expected lifetime of a couple of hundred two minute matches.

Hi Mike,

If the piston is allowed to smack into the cylinder end-cap, the dynamic impact forces are far higher than one might imagine based on static pressure calculations. This is especially true if the piston shaft has a large mass attached. This is why a jackhammer is able to bust up concrete.

I'd like to see external stops. Then the inspector doesn't have to make a subjective judgment.


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