Gelcoat chip

[DanielC]

RE: Re: RE: Re: RE: Gelcoat chip

If I had no gelcoats handy to repair a chip in the gelcoat below the water line, I would consider using fingernail polish. It would be worth it to help keep the repair from getting worst from water pressure from a moving boat.
Having said that, I would repair it correctly with gelcoat from spectrum color at the earliest possible opportunity.

[KD7000Guy]

RE: Re: RE: Re: RE: Gelcoat chip

8122,


I must say, I do get a chuckle reading your replies...I get it, your are a resin expert.
If you actually read my whole post, you would see that I was recommending it be fixed by a pro because its not an expensive fix and it can be tough to match colors. The nail polish was TEMPORARY!

[TRBenj]

RE: Re: RE: Re: RE: Gelcoat chip

I see Pete's point- I doubt the nail polish was harmful, but its unlikely that it helped in any way either. No need to offer advice if it doesnt have any value.

I have one or 2 chips in my '90 that I havent gotten around to tackling yet. Since the epoxy resin used in the hull (CC went to AME4000 in 1989, I believe) isnt in any danger of absorbing water, the damage is purely cosmetic. No need for a "temporary fix".

[DavidF]

RE: Re: RE: Re: RE: Gelcoat chip

I will chime in here (why not?). The small chip is no way harmful. Putting finger nail polish in the chp is in no way harmful. BUT, when someone goes to do the repair, it will be extra work to make sure the finger nail polish is thouroughly removed (via sanding or grinding) so that the gelcoat will mechanically bond to the fiberglass laminate. With that said, an untreated chip must be thouroughly sanded/grind to get out any contaminants and to roughen the surface for a good bond. Direct water contact to the fiberglass laminate is not harmful in anyway...even with conventional polyester resins. Gelcoats only two purposes are cosmetic and as a mold release.

[8122pbrainard]

Re: RE: Re: RE: Re: RE: Gelcoat chip

keep the repair from getting worst from water pressure from a moving boat.

Daniel,
I don't recall us disagreeing on anything before but I have to on this one.

Unless the surrounding gel next to the chip is already fractured from the fiberglass and resin hull, the hydrostatic pressure from the boat moving through the water will not enlarge the damaged area. Think about it - If true, we would have lots of boats running around with lots of missing gelcoat!!

[DanielC]

Gelcoats, epoxy resins and especially polyester resins are not absolutely waterproof.
There are a few boats from every manufacturer that get gelcoat blisters. This is from water getting through the gelcoat. Thankfully, the epoxy resin used on Correct Craft boats are much more resistant to this problem.
I am NOT RECOMMENDING FINGERNAIL POLISH AS A GELCOAT REPAIR! It is a possible temporary fix. The cleaning and grinding, and cleaning again to an area that will be repaired will remove the fingernail polish completely, if done correctly.
Polyester resins are water inhibited. That is why polyester resins remain tacky on the surface, unless covered by something, a sheet of plastic, wax in the gelcoat, or the inside of the mold.
There are two different processes that happen when gelcoat cures. First, a solvent evaporates. While this is going on, the molecules in the gelcoat are forming bonds with each other in random chains, growing longer. These chains of molecules intertwine, and the gelcoat changes from a liquid to a gel, to a solid. When the gelcoat has turned solid, not all the solvents are gone, and they continue to evaporate, and the gelcoat does continue to shrink. It leaves behind a slight porosity. This porosity water molecules can penetrate. That is why we apply wax to gelcoat. It helps protect it from water.

[Hollywood]

I don't apply wax to my hull. Water is going to get through, I want it to be able to get back out again.

[DanielC]

That is fine. I wax the bottom of the boat that is moored because it makes it much easier to clean the slime off it.