Gentlemen, please explain what I'm doing wrong. I have been patching tubes for thirty years and am lucky to have maybe a 50% batting average with respect to a patched tube not slow leaking afterwards.
Checklist: I'm not stupid. I have a good patching kit (I typically use the Rema kit and patches.) I use fresh vulcanizing fluid. I follow directions, including roughing up the area, applying a thin layer of fluid, waiting five minutes, and then carefully pressing the patch down from the center out. But even when I do all these things, I often get slow leaks. And during the subsequent second attempt, I often note that the patch simply isn't sticking that well to the tube - it is pretty easy to pull it up from a corner. Shouldn't a properly-applied vulcanizing patch weld the patch to the rubber of the tube?
My theory is that there is often something on the tube which is preventing the fluid from working properly and from getting good adhesion. Would some alcohol wipes help? Would wiping down the tube with something a little more aggressive (e.g., lacquer thinner, MEK, acetone)?
I'm tired of messing with this to the point that I often just put in a new tube and throw the old away, even for the first puncture. But that seems like a waste.