Originally Posted by
cyccommute
I said that it take longer than 30 seconds. You implied as much. Letting the solvent evaporate overnight doesn't hurt anything. It's excessive, sure, but it doesn't hurt anything.
As for applying pressure with a book or a c-clamp or your car or whatever, that is totally unnecessary. If the glue is dry, pressing the patch in place with your hand is more then enough pressure.
Okay, you're right. Applying pressure, such as using a C-clamp does, however eliminate the void spaces between tire and patch, which will improve the seal and bond-strength. If you repair on the road, inflating the tube against the tire casing generates similar high pressure. It's physics. It may be unnecessary. It can't hurt for at-home repairs. I used to patch on road, no problems, but replacing with a fresh tube is faster, then repairing at home at my convenience has been fine.
On the "glue", I don't think it is actually dissolving the butyl, as occurs with styrene model airplanes and toluene-solvent cement, which is a "chemical weld". For example, if this were the case, when you apply the compound to the tube, the ridge should soften. I've never seen this happen.