"Tom Gardner" wrote:

In this pic, you can see a cam that operates a lever that is part of a wire
cutter. This is an old pic and we now use a roller instead of a cam but the
chain drive is the same. I want to replace this whole drive mechanism with an
air cylinder to move that lever. I roughly figure a 2" bore x 1" stroke will
have enough guts.

http://metalworking.com/Dropbox/_200...ob290-head.JPG

I cant get that picture to load but google programmable limit switches. They use an
rotary encoder connected to a control box which provides the switching.

Wes