Join Date: May 2012
Location: North Vancouver, BC
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Re: Blister repair prep
The blister is a result of water in an isolated pocket. once you have ground back the problem area, you shouldn't have to worry about moisture elsewhere. A wipe with acetone should be fine.
The only way to permanently fix the blisters is to grind them out to expose the void, then fill them. I used a rasp bit on a drill to grind the blister back until I have exposed good fiberglass. (you will find the blister is likely a spot where 2 layers of glass didn't bond together.) Then you use a clear coat of unwaxed resin to cover the exposed surface. After that fill the "divot" with resin thickened with micro balloons. Sand that smooth, and then apply another clear coat of resin to seal up the repair.
I had a boat with quite a few blisters, some quite large, and I used the above technique. It didn't really take that long. Just a few days on the hard, but after that, I never had the problem again!
1979 Santana 30 Tall Rig
Last edited by SchockT; 09-23-2012 at 02:57 PM.