Dog Gear?

[jgannon]

Originally Posted by de_

Isn't there 2 inherent weaknesses in a AM shifter used as a release mechanism given the forces the kicker could be putting on the dog. There is a small 3/32 pin through the dog to connect it to the internal pull shaft. If you use the air cylinder connector, it has a tiny bearing with an smaller roll pin running against it. Last I heard both pins have occasionally broken using 26lbs of pull force with a 3/4 air cylinder. Now I hear people have to use 1.5" air cylinders to trigger a release. Surely those pins are going to break.

In 2007, we naively ran the 3/4" bore cylinders in our AM shifters at 60psi. The spring pins sheared before ship date. I'd estimate that we didn't shift them nearly as many times as a typical kicking system would be expected to fire, so I'm surprised to hear that people are doing this successfully. Has the design changed?