Gel coat chips after pressure washing?

[RECESS]

I am just about ready to paint my boat and I spent this weekend pressure washing the bottom. I found that there are some gelcoat dings. Some of these had been painted over by the previous owner and some were created by the pressure washing. The fiberglass under both the old and new ones looks great. What is the best way to deal with these chips?

Sand and apply gel coat?

Sand and apply marine putty?

Paint right over them?

 

[Tom Spohn]

Looks to me like you have bottom blisters. You should not just paint over these. Suggest you have a good boat yard take a look.

 

[sailaway78]

Not Blisters Exactly

These appear to be more of a pox. Very tiny blisters, which are just gel coat blisters. If they do not go past the gel coat, is a pretty easy fix. There was a thread here on this fairly recently. Usually not a big deal, but do some research, and have someone knowledgable take a look. But it certainly is not the big deal that bigblisters can be.

 

[RECESS]

The largest is no bigger than the end of your pinkey finger. I have done some searches but did not think of them as blisters because they are so tiny and the edges are really solid on the fiberglass.

 

[Hermit Scott]

The cheapest solution that will last is to sand off any thing that looks suspicious, acetone everything and paint the bottom with interlux 2000e. Then apply your bottom paint. You can seal bare fiberglass with that stuff and not be concerned with gelcoating.
If you don't fix this correctly you can have a problem with your bottom paint not sticking.
Is your boat kept on a trailer usually or is it in a slip?

 

[RECESS]

Kept on a trailer with the mast up most of the time. I am going to grind down the edges and surounding gelcoat and apply gelcoat. I want it all done right, even if it delays me a couple days. I have been slaving on this boat for 4 months now and I am not about to take any shortcuts now. The great thing is it is all downhill after I finish the gelcoat fill. I have sanded her down and done so much prep work she is as ugly as she is going to be. I have everything to put her back together and be very pretty and the structure will be outstanding. I got her because she was so solid.

After todays bottom pressure wash. I am itching to get the primer on and get her painted! I have sanded until I can sand no more!

 

[Steve Dion]

If you are not going to do it right, then why do it at all? Check out West Systems they have a method to repair it properly. You will need to sand it down and apply a couple coats of Epoxy to reseal the bottom after the repairs are made. Then you can paint it with bottom paint.

 

[Hermit Scott]

Sanding isn't that tough, so long as you have a 7" variable speed sander woth 80 or 40 grit paper, not orbital but circular. Harbor freight has one for $35 or so and it's gauranteed to last at least until you sand the bottom of your boat.
I would rather have interlux 2000e applied to the bottom rather than gelcoat. Gelcoat is not water-proof. Interlux 2000e is waterproof. If you sand off the outside layer and waterproof you MAY avoid further gelcoat bumpies. If you do not you will probably get what you have been getting with gelcoat.
Are you going to gelcoat the topsides?
I really like the way Oday boats look better than catalinas. I wish I had an oday30.

 

[RECESS]

I am going to use Interlux Perfection topside.

I have the sander. I am going to get the Interlux 2000e this morning.

 

[sailingdog]

If the blisters were dry on the inside, not filled with nasty acidic liquid, then they're gelcoat voids rather than osmotic blisters... in that case, just fill with thickened epoxy, sand fair and paint. If they had nasty brown acidic liquid oozing from them, they're osmotic blisters and you'll need to dry the hull out.

 

[Ron20324]

Recess, would this be a good time for you ($$$) to get the hull soda blasted and start from scratch so you know what's on the hull?

 

[Bad Obsession]

I agree with Ron on that one. I am planning to do that to my Catalina 30 in the near future because I found blisters on her. I want to soda blast it, repair the blisters, barrier coat it, and then bottom paint it.

 

[kendall]

If the boat has a lot of trailer miles, they could just be road rash from gravel, sand and other road debris being thrown up by the trailer tires.

Does the trailer have fenders, or are they removed for work being done? If you have them, do they fit close to the tires?
If you don't have them, install some that fit close to the tires, and install some mud flaps on the tow vehicle.

In some areas it's pretty common to see cars and trucks with a soft rubbery spray on the lower sections of the rear fenders and on the rockers behind the tires to protect against it. Some come from the factory with the same coating.

Won't say that's the problem, but I've seen it enough that I look into road rash before assuming blisters.

Ken.

 

[RECESS]

They are all dry and almost all of them are behind the tires or above them. There are almost none in front of the tires. The trailer has no fenders.

Unfortunatly, I live rather far from a yard to do a soda blast. The nearest boat yard to me is about two hours away.

 

[sailingdog]

Recess—

Most of the Sodablasting vendors I've talked to are trailer based, and will come to your boat. Due to the location of the pox, I'm betting that it isn't gelcoat voids or pox, it is due to road debris.

 

[kendall]

They are all dry and almost all of them are behind the tires or above them. There are almost none in front of the tires. The trailer has no fenders.

Unfortunatly, I live rather far from a yard to do a soda blast. The nearest boat yard to me is about two hours away.

That is consistant with road rash. Having the chips wash out with a power wash is also pretty common.

Best repair is to follow Sailingdogs advice, then if you plan to tow the boat for any distance install fenders. Tire hugging with mud flaps are the best way to go.

Ken.