dereknkathy

there are too many to treat individually. sand off the entire layer that is popping and repaint. you will be halfway done by labor day. or just bottom paint it and hide the blisters in long island sound. nobody will see them but the fish...

suss1173

Those blisters come off with very little effort. A low pressure power washer hitting them and they fall right off.

I don't think painting /or barrier coating over them will work as either would likely just flake off. I'm guessing I need to DA it with 80 or blast it and once they are all off my hope is the barrier will be think enough to fill the tiny voids where the gel came off and then be able to paint over the barrier and be done with it.

Hopefully glasdave or madbouy will veryfy or give a yay or nay.

badmonkey

Question, No one answered the question of "does the paint/gelcoat blistering have any structural effects to the boat...can blistering in the gelcoat create structural issues? Thanks for the insight from the pros (Glassdave)

glassdave

iTrader: (1)

no it does not have any real affect on the structural integrity of the boat. I suppose a poorly built poly boat after years in the elements would be compromised but surface blisters are not going to weaken anything. In theory the blister could act as a point of intrusion for water pressure but again it would have to be so bad you'd know not to go out in it.

CDShack

As a rule, no. Unless the blister is the result of fiberglass delamination underneath, it is mostly cosmetic. The opposite is generally not true either, that gelcoat blisters cause delamination underneath. Gelcoat blisters are often seen on boats that spend some time in the water, where the effects of the water and it's pressure causes air or defects trapped by the gelcoat to expand and blister. They are a pain, but cosmetic, and generally have to sand through the bulk of the gelcoat to rid yourself of them permanently, or they may reappear. I've never done one that I didn't turn the boat over (so my arms don't get tired!)

CDShack

Great minds thinking alike!

glassdave

iTrader: (1)

ohhhhhh man i HATE sanding upside down but it is one hell of a shoulder work out

suss1173

Yes sanding upside down is no fun! I just finished addressing this yesterday. It took me about 3 full (long) days of work. I started by wiping the hull down with Interlux 202. Then I DA'ed below the waterline with 80 grit. Once I got past the blisters, which were only in the gel, not in the fiberglass, I wiped the hull down with the 202 again and rolled on 3 coats of Interlux 2000E barrier coat. After the 3rd coat of 200E I rolled on 2 coats of Micorn 66.

It was a lot of work, but I am very happy with the results. Hopefully they don’t reappear over time.

CDShack

To me it's a whole lot easier (and a better job) to just pull the motor, drain the fluids and flip that dude over, although, I did blueprint the last 8' of my Scarab sticking off the end of the trailer with the engines out, but I was alot younger then!

The Polyflaker

Blisters are without a doubt VERY BAD for your boat no matter what u have been told. I've been in the structural marine industry for over 30 years as I was a mold sprayer, gel/glass repair, laminator and I pride myself as the best polyflake repair guy in the world !! I now only do consulting work for companies that are having way too much warranty structural problems to which literally will drain a company dry in no time. So I go in an I figure out why is it that they are having so many stress crack problems and such. Blisters are extremely detrimental to the whole bottom of your boat and if not fixed will ruin your boat. They come from leaving a boat that's not been "bottom painted" in the water usually as little as overnight. Gel coat can not be left in the water for no more than 12 hours at a time if so you are risking the chance of developing blisters. How do I know this?? because I have a close friend that is one of the leading edge chemists for poly/vinyl esters as well as epoxies and so on so forth. When I first started this trade way back in my Havasu days I was taught all the wrong ways to be working with gelcoat so I finally after so long searched for someone that actually knew what they were talking about so I made some phone calls to the manufacturer of the gelcoat and that is where I met John and from that point on I was well educated about gelcoat as well as meeting a life long friend.. Water is gelcoats worst enemy so you ask why is it some boats blister and some don't and you hear people listing off boat companies to which there is truth behind and that's because the same gel coater sprays all the molds they build usually so with that said too thin of gelcoat is what speeds up the blister problem but the actual problem is LEAVING YOUR GELCOAT IN THE WATER OVERNIGHT without some type of bottom paint to protect it. Just because boats are built with it doesn't mean that it automatically makes it waterproof !! Lol Yes I'm sure there is going to be a bunch of you here saying that your boat doesn't have blisters and that u leave it in the water overnight and the answer to that is that the gel coater who sprayed your boat sprayed in way too much gel coat thinking he was doing u a big favor so your boat wont blister with the trade off of having a brittle crack prone bottom. I have seen boats in my shop that came in blistered with the laminate so destroyed from water intake that they were never again used. All of those blisters are caused by the saturation of water that has made it past the gel coat thru the porosity that cured gelcoat unfortunately has and once the water makes it to the laminate it now has a place to sit and fester and eat away at your boat.. Each and every one of those blisters is an open wound for water to enter quickly into the laminate to which is a place where water was never suppose to be. People if u have any exposed laminate/fiberglass meaning the gelcoat is missing I cant stress to u how important it is that u get those little harmless chips fixed because fiberglass is really a big sponge and just sits there and drinks water up while your boat is in the water. Someone mentioned about how Triton boats always have blisters where the bunks are well let me tell u if u were to pull all boats off their trailers u would see that its just not them that has that problem. Why is it u ask ?? Its because what ? the gelcoat NEVER has a chance to dry out the boat goes from lake to lake water carpet then back to lake again get it??? Blisters are a direct result of gelcoat being left too long in the water PERIOD and YES THEY ARE HARMFUL AS HELL in fact THEY WILL DESTROY YOUR BOAT. I do urge anyone here that thinks I don't know what I'm talking about to come forward as I will give to them free education and that is something u just don't get anymore !!