Ok, so I've tried a few things and so far, this is the only thing that has worked. I no longer get those sweat blisters or deep cut lines or bumps. So far anyway. I went to CVS and got several different things to try and here's the current winner:
http://m.cvs.com/mt/www.cvs.com/shop/hom...uid-210000
Make sure it's this kind and not any other medical tape because I've tried other kinds and no, they do not work. Only this kind works. It sticks to itself, not your skin, it's very stretchy and breathable. It's about the same color as an ace bandage and mine is 2" wide. I don't know if the 1" wide would work.
Anyway, do not put it on the entire part of the rim that presses against your chest, or you won't get a seal with the suction. (At least I didn't). What I did was press the end against the outside of the rim starting at the bottom of the dome. As you work your way up and around, the tape should be 1/2 way pressed against the outside of the rim and 1/2 way sticking up in the air. Once you get half way around the dome (so, at the top of the dome), lay down and press down the 1/2 that was sticking in the air. So, basically fold it over the edge of the rim and press down. It will stick to the silicone. Finish running the tape around the other half of the dome, then again, fold over the part in the air and press down. Once you have both ends together, overlap one on top of the other at least an inch or more, then cut the rest of the tape roll off. So, you're covering the edge of the rim only and part of the tape will be on the outer edges of the rim that goes against your skin and part of the tape will be on the outside edge. I hope that makes sense
Even though you're only covering the outside edge of the rim, you're covering the most uncomfortable part and the part that digs into you. I'm guessing it also somewhat absorbs moisture because I haven't had those sweat blisters or any bumps at all while doing this, or any deep lines or irritation. And also only covering half of the rims so that you still get a good sticky seal.
When I'm done pumping, I removed the tape, dip it in alcohol, wipe my rims & domes with alcohol and lay the tape flat to dry. It's sticky the following night so I can reuse it. I've only done this a few nights, but so far so good and I haven't had to use new tape yet.
Make sure you're flipping your rims outward when putting them on
I also don't use the brava filters. I fold up toilet paper and put it in my domes, but I'm going to try the coffee filter tip!