Mark, Ya Know, that's interesting.
I get a little nib about 1/2 the time. I've always thought it was
something I was doing wrong, but I'm not sure what. I try to leave the
clear plastic on even after mounting the tube, but it usually falls off
before. The hardest part for me is getting the patch centered. I've
developed a method to do that, but it takes too long. And yes I use
talcum powder, despite highly regarded advice to the contrary.