[ThirteenOfTwo]

"This won't fire. You've got two air pipes going to a single-acting piston. All the air goes out the one that's not connected."

"Well, let's put a closed safety valve on one and try it."

Later...

"This still doesn't work. Your system will never retract; I'm not firing the pneumatics right now but the pistons are stuck in the out position. The force of the internal springs can't overcome the force of the air."

"Can't you retract a single-acting pneumatic piston by dumping all of the air that's forcing the piston into the out position?"

"...so remind me where we're dumping the air now. Is it into the piston, or is it into the closed safety valve?"



"Hey, look! Instead of completely redesigning and starting from scratch, you took my very simple advice and applied it to make the system incrementally better, and now it works! Who would have thought?"