Hi. Mouse chewed a hole in my Achilles Expedition raft. It's been in storage for 5 years so got it out to prep for the Grand next spring and dammit. Just one hole, about .05 cm diameter. The problem is, the patch keeps getting a bubble and eventually the bubble works its way to the edge and it's leaking again. I thought it was the old thick shore cement so yesterday peeled it all off, lightly sanded again, and placed a new patch with a new batch of cement. Happened again. Is it too hot? Maybe sun expansion put too much pressure on the patch before it was cured? Been hitting >80 F up here in the mountains. Any ideas?