wrote in message
ups.com...

Reggie Smithers wrote:
chuck,
Do you not recommend popping the blisters, allowing the blisters to dry
out
and applying an epoxy coat? That doesn't sound exotic, and I thought it
would be prudent for any boat that is kept in the water.


Such a "surface" treatment is about all the trouble the situation
really warrants.
And anybody who convinces a boater to stick a boat into a "drying tent"
and spend $1000's in lay days (or lay weeks) to cure blisters should be
ashamed.

One of our local yards does a very good job of blister repair. Their
process involves a peel job and then the application of a few layers of
vinylester laminate under a new barrier coat. They put a lifetime
warranty on the process, and in ten years they have had only one or two
boats back for a re-do. They are the local exception.

Most blister repairs fail. Some sooner than others. The good news is,
for the vast majority of blisters there is absolutely no reason beyond
cosmetics to deal with them at all. 99% of the time they are out of
sight below the waterline.

I had a batch of chine blisters that I dealt with two or three bottom
paint jobs ago. Just sanded them flat, let them dry for a few hours,
faired them out, and slapped on the bottom paint. Cost was less than
$100. I fully expect to see those same blisters back again some day
(but maybe not)........and if I do I'll spend another $100 to deal with
them. That's much better than spending $10,000 or $20,000 or maybe more
to deal with them and *still* having them reappear in the future.

Delamination, of course, is another and very serious problem.
Blistering does not "progress" to delam, although in very rare cases
blistering may be an indication of an underlying delam problem. Got
delam? You're going to have to deal with it whether you see blisters or
not. Got blisters without delam? No big deal. Taking a drastic course
to remove them would be like spending $20,000 to have a surgeon remove
a benign mole from your butt cheek- it isn't hurting a darn thing and
almost nobody will ever see it.


The microwave concept is really a pretty neat idea at first look. An
improvement might be to just treat the blisters and surrounding area. No
need for a screen room. Just a directional microwave. They do it for
termites, just monitor the temperature, to avoid superheated areas, that
would explode. use the mw to heat the water up to a simmer. Might even be
a good way to check for osmosis. Moisture meter is not going to really
check for water behind an area of good gel coat. It can not sense the
water, and if it is a density checker, extra resin or glass is going to
change the readings. mw the hull and check for hotter spots. Like Chucks
blisters. Use the mw to accelerate the drying. Would be cheaper than
vacuum drying. A lot less time. Or use it in combination with mw and
vacuum drying.