artguy,
Hello... OK I'll try to give a quick "Splain it to me lucy"..
The "Air valve " that you need to run this type of cylinder (Dual stroke) is a Valve that has three positions...
1. Off Center position ...Need this so you valve off the air supply from cylinder... various reasons
2. "Up" to make the cylinder retract ...either "A or B " outputs
3. "Down" to advance the piston to press mode.
PS: Use the valve....it's a "no brainer" and does not cost much
Regards Fred
Here is a link to a good place to look for a valve and assorted parts
Parts