Originally Posted by rcarte11
By linking the two 3 ways (This is were machining my own would be nice!) the trigger pull would close off the LP to the first three way and open the second allowing the air to drive the ram. Once the built in QEV of the ram cap exhausts the air the spring should return the ram. Thus the LP air from the LP reg should still be blocked until the trigger is released. I hope to be able to adjust the air chamber to get the proper volume to drive the ram and act like a dwell.
What do you all think?
That sounds plausible, although not particularly air efficient, since you're looking at several inches of hosing to rig all the switches up. Also, I'm not entirely sure how you plan on having the air chamber seal itself from venting back into the 2nd 3-way or having its backpressure log the switch. It would probably make more sense once I saw your diagram.
One idea I had was to tap the exhaust port on the ram for a hose that would lead back to the 1st or 2nd 3-way and act as a cutoff- so that as soon as the ram reaches the end of its stroke the gas being sent to the primary 3-way would be cut off by the "sensor" hose. So the "off" the 3-way would need to be upstream of the "on" 3-way and both would need to be spring-returned and tied to the trigger.
But, now that I think about it, this would probably require even more hoses.