Bottom questions

[Texastailboard]

Hey everyone we are making progress on Perseverance, hullsides are painted and now working on topside. I have some concerns on our bottom. I know Hatteras have blisters but since we have been on the hard for over a year it is time to truly fix and seal that problem. My question is we have lots of the small 1/4 or smaller blisters and probably 1-2 per sq ft in at least 1/3 of the hull. If that makes sense, we have gelcoat damage in certain areas and some areas are fine and nothing but the small stuff. Surprisingly I haven’t found any to actually have damage in the fiberglass, all are in the gelcoat. The two pictures are a typical section of our hull and the other is an area that we had some rub damage from hurricane, my painter used 24 grit on a grinder to grind off gelcoat. I know some say fix the large ones and some say peel or grind off gelcoat. I would love to have your insight, we’re trying to make a plan to move forward ThanksBrooks

 

[dsharp]

You can do a lot of damage with a #24 grit disc if your not careful. I wouldn’t peel or grind off the gel coat. We used to do it that way then moved to blasting. If the yard will let you sandblast, that is the fastest way to bust the blisters. #3 or #4 will remove all of the paint and open the small blisters in the gel coat. Then it’s a matter of filling the blisters with an epoxy fairing compound followed be 2-3 coats of a barrier coat. We sold our yard in the early 80 ‘s so Products and methods may have changed.

 

[jim rosenthal]

What he said, absolutely. Don't peel or grind the bottom. THOROUGHLY dry it (this takes weeks to do and may require tenting the boat with fans to circulate the air) then blast the hull to get all the paint and loose gelcoat off and open up the blisters, then more drying, then fill and fair (VC Watertite, or West System, or similar- like he says, new products are around now) and ten recoat the bottom; use Interprotect, or 3M vinylester resin, or West System.

My boat was done with VC Watertite and Interprotect, many years ago, now. It is still fine. As you say, the damage is in the gelcoat, not the laminate, and much of the gelcoat will still be okay. Just replace what you need to, and don't peel or grind off the bottom.

I have hauled my boat every year for Nov-March, and I think that has helped the new bottom hold up as well as it has.

 

[SEVEN]

You should have sand blasted a year ago and let them dry out. I’ve seen it take months. Hope your not in a hurry.

 

[Texastailboard]

The boat has been sitting on the hard for a year and half. A few years prior we had the hull wet blasted which popped the tops off the little blisters and all of the larger ones I have chipped the gel coat off are dry and no damage to the fiberglass below the gelcoat. I am going to check into the blasting again or try our sandblast attachment we use on out 5000 psi pressure washer. It cleans our equipment prior to paint pretty well, just slow and tedious. I was very scared of peeling or grinding. I was glad to hear y’all thought the same way.

 

[SEVEN]

Make sure to use a moisture meter and verify the glass is dry. Power washing will add water. If dry you’re good to patch with Epoxy and coat with barrier coat. Good luck.

 

[krush]

Do what you can. But seriously, if the boat has lasted this long with a few blisters, I'm sure it will last plenty longer!