petn7 wrote:I don't use anything and the bag deflates just fine with help from the vacuum.
Same here. I use a schraeder valve controlled by servo, no rubber bands to assist. I do use a rubber band around the leading edge of the bladder to keep it into place (snug against the wtc).
The vacuum within the cylinder created at bag inflation does a nice job of sucking the bladder air back into the wtc. If this process is happening too slow for you, I can think of 2 possibilities:
1). too much restriction on bladder air return line
2). too much volume of air left in wtc after bladder is inflated. Maybe you have too little or no vacuum in wtc after bladder inflation. Bladder too small?.....wtc atmosphere compartment(s) volume too large?