Hi, About a month ago I asked for some advice regarding gelcoat repair, and I thought I'd let you know what I ended up using and how it turned out. Materials I used: SeaFit Gelcoat Patch, 2 oz tube Marine-Tex putty, small jar with liquid catalyst, white Sandpaper in 180, 400, and 600 grit I bought all the materials at West Marine in Woburn, MA. During my launch on a trip to Thatcher island just of the coast of Rockport, MA, I put a divot in the prow of my kayak just below the seam. I was launching from the boat ramp at Granite Pier, and after getting myself into the boat, I was distracted trying to put my sprayskirt on the coaming and drifted into the pier. Crunch! I just didn't think I was going fast enough to cause any damage, but the pier's enormous, rough granite blocks can cause damage even at low speeds. Because the damage was at the prow of the boat, it seemed to me that the "hole" made by the cracking of the gelcoat was deeper than it might have been on a flat part of the bottom of the hull. First stage: I used the SeaFit gelcoat patch, white. This comes in a tube and doesn't require any hardner or anything. It starts out as liquid, and then swiftly approaches the consistency of slightly warm marshmallow Fluff. I found that it kept flowing towards the bottom of the divot, leaving a gap at the top. I tried to remedy this with a second coat where I used masking tape and waxed paper to hold the material in place. I still ended up with unfilled portions at the top. Of course, gelcoat shrinks as it cures, and overall, while the new gelcoat patch covered and sealed the fiberglass patch underneath, it wasn't near even with the original gelcoat`. Second stage: I decided to try Marine-Tex putty. I had had experience with Bondo on cars, and it seemed similar to me, except unlike Bondo it wasn't single-stage, it needs a hardener (which comes with it). I found the Marine-Tex putty pretty easy to work with. It filled the hole handily and sanded well. As a listmember warned, it did dry darker -- it was slightly gray when finished. Just to see what would happen, I roughed up the MarineTex with some of the rougher sandpaper I had on hand and painted on a very thin layer of the gelcoat patch material. This worked like a charm, and after sanding, I don't think you can see the repair unless you know where it is and put your face up right next to it. Things I would do differently next time: I'd get more spreaders/mixers (little popsicle sticks would do fine) and a set of small plastic putty knives. Otherwise, I think the gelcoat/MarineTex/gelcoat formulation is a good one. I think it's a good idea to put an initial layer of gelcoat into a hole, because it's less likely to have air bubbles than the putty, even if the initial coat flows or is uneven. Then you can cover the uneveness with MarineTex and do some cosmetic finishing with gelcoat patch material if you want to. Lisa ______________________________ lisa_at_cadence90.com bikes, books, internet radio *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Great story and soooo full of details! My own experience is the gel doesn't want to stick to the Marine Tex very well. i guess it worked out OK for you. Time will tell! I usually forgo the gel coat and use the MT 'straight up'. who cares if the colors a shade or two off. RRRRR steve -------------------------------------------------------------------- mail2web - Check your email from the web at http://mail2web.com/ . *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Thanks! I agree regarding the cosmetics. I don't like my boat to look ugly, but there are a lot of parts of my boat that no one will ever see anyway. It's certainly the case that MT was the "lion's share" of this repair, structually and in terms of getting the repair to be even with the pre-existing gelcoat. Mostly, it was there and I just wanted to see if it would work. I think rough sanding the MarineTex made a difference. Since I sprayed the MT with a water bottle before I started sanding, it occurs to me that it may have been a little damp. Maybe this made a difference? Unknown. One thing I did do with the gelcoat is to spread it out on a piece of cardboard that had a waxy surface (it was the outside of a color-printed product box). Then, instead of trying to spread it on like peanut butter with a spreader, I used a small, nail-polish like brush that originally came with some of that "ding repair" paint you can get at auto supply stores in the tiny little bottles. (that I use for my bike to inhibit rust). The gelcoat appeared to run into the little grooves caused by sanding and sort of spread out into them. Once it dried it appeared very flat and shiny. Lisa ______________________________ lisa_at_cadence90.com bikes, books, internet radio -----Original Message----- From: aldercreek_at_qwest.net [mailto:aldercreek_at_qwest.net] Subject: RE: [Paddlewise] How the Gelcoat Repair Turned Out Great story and soooo full of details! My own experience is the gel doesn't want to stick to the Marine Tex very well. i guess it worked out OK for you. Time will tell! I usually forgo the gel coat and use the MT 'straight up'. who cares if the colors a shade or two off. RRRRR steve *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Lisa and Steve, I just had my fiberglass boat repaired because while launching in some ugly surf several weeks ago, I wound up doing a "reverse pearl". As the boat fell back on top of me, it was sucked off by the surf. The stern then hit some underwater rocks, and took several chunks of gelcoat off of the stern while the flexing of the hull caused a crack in all of the fiberglass layers a couple of inches behind my skeg. In addition, the gelcoat had been wearing off of the keel as a result of abrasion from sand over the years. After looking at the repair work necessary, I thought it might be time for a professional. I brought it to a local shop who said they would cut out the damaged glass and replace that with 4 layers and then use MarineTex to fill in the gouges in the gelcoat and also cover the fiberglass on the keel where the gelcoat had worn. I have to tell you, the repair looks good-not quite as pretty as gelcoat, but my boat gets used and is no longer new. And as the repair person said, you're only going to be wearing any gelcoat off of the keel again anyway, why not put something on that will last a little longer. Besides, all of the repairs are underwater while I paddle. BTW, my MarineTex is white (actually slightly whiter than my hull). I understand it comes in two colors, a grey and a white and a fast setting version that only comes in grey. I carry that in my repair kit. Steve *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
On 19 Jun 2003 at 10:15, Lisa Williams wrote: > I found that it kept flowing towards the bottom of the divot, > leaving a gap at the top. If you have problems with the gel coat getting too runny, add a thickening agent to it. Silica flour (collodial silica or Cabosil) works well. You can also use microballons or wood flour. > I'd get more spreaders/mixers (little popsicle sticks would do fine) > and a set of small plastic putty knives. When we bought our house, I found an artist's spatula in the basement workshop. It's about 2 inches long and shaped like an elongated diamond (like a trowel). Fairly flexible but nicely springy. I find that it makes a nice tool for working gel coat and epoxy - especially if it's a bit thick. Mostly good for working on odd shapes. For smooth areas of the hull, plastic spreaders are better. Mike *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
"Lisa Williams" <lisa_at_cadence90.com> wrote: >Of course, gelcoat shrinks as it cures, and overall, while the new gelcoat patch covered and sealed the fiberglass patch underneath, it wasn't near even with the original gelcoat`. >...I'd get more spreaders/mixers (little popsicle sticks would do fine) Little spreaders or "squeegees" can be used to fill small divots. They scrape excess off the high areas, leaving only the "valleys" filled. Either prop your boat so the repaired surface is horizontal, wait a bit until the gelcoat "gels", or use more tape and waxed paper. Using a little colloidal silica ("Cabosil" or silica fume) will make the gelcoat tougher. Silica fume is a "thixotrope", which means it is non-sag. Household baking flour is also a thixotrope. Shawn __________________________________ Do you Yahoo!? SBC Yahoo! DSL - Now only $29.95 per month! http://sbc.yahoo.com *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
This archive was generated by hypermail 2.4.0 : Thu Aug 21 2025 - 16:33:34 PDT