Small Gel Coat Repair

petemos · Posted: Thu Jun 02, 2011 3:16 pm Post subject: Small Gel Coat Repair

Hi Guys. I've looked thru most of the topics on Gel Coat repair, but I just must be dumb and just don't understand the process for a small chip. I still have the cans of gel coat that the factory gave me with the boat, but I’m not sure whether I just need to stir it up and then inject or trowel it in and I’m done, except for some sanding?

Is there something else I have to mix with the factory gel coat to get this to harden or does it just cure? Also some people say it should be covered to cure, some with plastic, some with mylar, some nothing. As I am in Nova Scotia and was unable to attend the factory gel coat demo, any help in clearing this process up would be greatly appreciated.

I would attach a picture of the chip, which I’m sure someone has dealt with. It’s about ¼” and just Gel Coat deep, but I can't seem to figure that out also.

Thanks again.

Jim

thataway · Posted: Thu Jun 02, 2011 3:53 pm Post subject:

All polyester resin needs a catalyst. Methyl ethyl ketone peroxide
is the catalyst. 2% to 3% is the correct ratio.

You want to feather out the defect, using 400 sand paper. Mask off the area, and then wipe it down with acetone.

You can either add wax mixed in styerene to the gel coat -3%- (assuming that it is still good--4 year old gel coat may have hardened, and be unworkable) You can get gel coat from the factory or Spectrum Color, spray on PVA or occlude the surface with mylar or Suran wrap.

I like to spray on gel coat, and then spray on PVA (Poly vinly alcohol, which has wax on the surface--it is green so you can see where it has been sprayed).

If the chip is very deep, you may have to use a filler with the first coat of gel coat--use enough fumed silica (cabosil) to make it peanut butter consistance. After that cures, sand it smooth, and then spray on the finish coat. You can sand with a sanding block, wet 400 to 600, 800 and 1200 sandpaper, than Finnesse it by 3 M to polish it out to match the rest of the boat.

petemos · Posted: Thu Jun 02, 2011 5:21 pm Post subject:

Thanks Bob for the Info.

What do you consider deep enough to use filler? I can see a black area in the crack and its maybe it’s a 16th of an inch deep.

Adeline · Posted: Thu Jun 02, 2011 9:30 pm Post subject:

Years ago I picked up a tube of "SeaFit Gelcoat Quick Fix" in Buff-White at West Marine and it was a perfect match for Adeline's 1989 Gelcoat in "Colonial Ivory".

Easy and quick solution for a minor ding.

I just checked and it looks like it is now called SEAFIT RESIN
Gel Coat Scratch Patch

I don't know if your 2007 "white" is the same shade as my '89 or if they've changed the product at all.

Worth a shot. Thumbs Up

thataway · Posted: Thu Jun 02, 2011 9:52 pm Post subject:

If standard gel coat would run, then you need to do the filler first. If you can lay in enough standard gel coat--then you can skip the filler step. So it really depends on where the chip is on the boat.

sjboysen · Posted: Fri Jun 03, 2011 10:26 am Post subject:

Jim,

Unfortunately if the gelcoat that you have came with your boat than it is not useable. It is not a total loss though, look in the yellow pages first to see if you have a fiberglass repair facility of any kind near you, if so give them a call to see if they can do a quick color match of your existing gelcoat that you still have. I have found that most places, if they have something close in color are willing to help you out.

Now more pressing do you have a chip or a crack, you referred to both in your post? If it is a crack then there is more detailed work that needs to be done other than just filling it and spraying gelcoat on it. Let me know and I will guide you through the rest of the process.

Sincerely,

Scott

thataway · Posted: Fri Jun 03, 2011 3:29 pm Post subject:

http://www.spectrumcolor.com/default_main.asp has both a paste and liquid gel coat which can be used to match the hull color. (assuming that the gel coat you have is not usable).

petemos · Posted: Sat Jun 04, 2011 9:38 pm Post subject: Small Gel Coat Repair

Thanks Guys for your comments and assistance. The clip is on the side(horizontal ) so I guess there is a chance of it running, but based on some other things I’m an reading, I think i can layer it up with several coats, while masking off any area’s that the gel coat may run into.
I am interested in Scotts comment that the gel I have is not usable.

I opened up the can and while it may need a good stir, it’s still liquefied. There seems to be a oil based layer on the top with the pigment lower down. As I was not going start this job without complete info, I just re-sealed the can and put it back on the shelf.
Scott is there a shelf life on these cans of gel coat and or gel coat in general.

Thanks Again.
Jim

sjboysen · Posted: Mon Jun 06, 2011 9:29 am Post subject:

Jim,

Shelf life for gelcoat is approximately 6 months. Since you have it you can try mixing it up and see what the color looks like.

If the repair is a chip I would not try to layer on gelcoat as on a vertical surface this doesn't work to well, I would mix in either some thixo or Cabosil which you can get at any fiberglass repair shop to thicken up the gelcoat then put it on.

Let me know if you need more information and I will gladly help.

Sincerely,

Scott

petemos · Posted: Mon Jun 06, 2011 1:39 pm Post subject: Small Gel Coat Repair

Thanks Scott as I'm back in the USA for the month, i'll have to wait till the end of June to try the try the "mixing it up and see what the color looks like" project. Otherwise i'll just leave it till later in the season and pick up everything at once to do the job. i'll then start on a smaller chip i have on the bow just above the rail. not many people will see that spot if i mess it up.

Thanks again

Jim