Use lots of thin layers and wait a day between layers. Here's what I think is happening. The mixture dries by the acetone evaporating. If you use a thick mixture the acetone on the surface evaporates first preventing the acetone underneath from evaporating. With no way to evaporate the acetone now eats away at the boat. Some people think that the mixture has already dried when the acetone on the surface has hardened and apply another layer. Wrong! Wait one full day between layers.Be careful with the abs pipe and acetone mixture. It may be OK for filling a gouge or two, but I have seen boats delaminate and turn to mush on the bottom after it was applied in large areas.
Jim
