[wrndln]

I to, had a hole develop in the media pickup tube after a lot of blasting in my TP Tool's blast cabinet. The glass beads must really wear on the plastic tubing, especially where there is a bend in the tube. I never though glass beads would cause a hole like other shape edged media would, but they did. Being cheap, I just taped the hole up with electrical tape and so far it is holding. I will soon need to replace the tube with a new one. If your gun looses effectiveness (assuming the pickup tubing isn't clogged), the first thing I would do is inspect the media pickup tubing for a hole.
Rusty Nelson