Bottom Blisters, Stripping and Painting

[treeder65]

[FONT=Verdana, Arial, Helvetica]I recently began stripping off the old bottom paint on my 1986 fixed keel Catalina 25. I used Peel Away I at first; it seemed a little bit too aggressive, as I noticed small, 1/8" - 1/4" sized blisters along the water line. I might be mistake though. The blisters might have been there all along, but were hidden by the "boatload" of coats the PO had put over the moon surface like chipping coats. Would an aggressive stripper cause this or is it more likely that they were there all along. Some are still just gelcoat bulging, but most are already "popped."It is definitely gelcoat and not paint. None the size of dimes or quarters that most people post about. I have switched to the marine Peel Away; it's probably the same thing watered down just so you don't have to babysit it.

The questions I have are:
1)Could it have been the stripper, or would that remove the gelcoat in a similar manner as the paint (just melting it away into a slush)?
2)Should I apply a barrier coating before painting?
3)I ordered some West 105 with some 407 low density filler for the blisters (as per the West site recommendations). Is this the best way to fill small blisters?
4)I store the boat out of the water on it's trailer and launch every couple of weeks during the summer. Is VC-17 the best paint for trailer sailing? I only go into salt water a few times per year for about a week at a time in the water.

Thanks in advance for any advice.[/FONT]

 

[Ed Schenck]

The stripper should not affect the gelcoat. Anyone who uses a chemical stripper to get down to gelcoat would have cause to sue. If there are blisters the boat must have spent part of its life in the water. But you are dry sailing so future blisters should not be a problem. Thus no need to barrier coat. Sand the newly exposed gelcoat lightly with 80-grit, clean with whatever the VC17 can recommends, and paint.

As for the blisters just do as you have read with the West System literature.

Over the years that I have been hanging around here there is consensus about barrier-coating. Older boats already have all the blisters they are ever going to get. So why barrier-coat? I ignored that advice and put on five coats of Interlux 2000E in 1999 when the boat was already twenty years old. Just in case you think you might leave it in the water some day.

 

[RichB]

I agree with Ed and echo the thought to use the barrier anyway. My 23 spent time in the water before I got her. Along with lots of barnacles I had small bumps in the gelcoat clustered just below the W/L and smaller than a dime. I ended up sanding the bumps smooth and did not sand through the gelcoat. So my "baby blisters" sounded-out ok and I used 2-part, high build epoxy by Sea Hawk in Clearwater, Fl. instead of the 2000E.

 

[higgs]

I concur with the above. VC 17 is very easy to maintain and it does not build up, thus sanding before reapplication is not necessary, unless you want that racer perfect bottom. I have used the stuff for 20 years and love the ease of maintenance. It is a good cold water paint, but since your pulling out every few weeks, I don't think it will much matter.