Someone wrote in about this subject with some questions on repair. So let's see what we can do.

First, Crazing gelcoat on a powerboat or sailboat is usually found in areas of no support or soft coring underneath. This lets the fiberglass area flex a bit and causes this condition. There are other reasons why, like the fiberglass just beneath was not done properly, and many other scenarios, but lets get to the fix.

A crazing area looks like the lines in a jigsaw puzzle. The cracks go in every which way. By applying Gelcoat or even paint, the crazing will show themselves again. Even if you sand them down, spread filler, then apply gelcoat or paint, the crazing/cracks will come back again because the crazing cracks are so small the filler can't get inside the cracks. Another reason is at every beginning and end of a crack has to be stopped by rounding out the ends with a small pick, punch or nail...anything that will penetrate the gelcoat fully and leave a rounded edge at the very end of the crack. This way it is very hard for the crack to continue.

Basically on a single crack, you want to open it up wider and round out the ends. Now the filler you use can do its job, and the gelcoat or paint can be applied. On crazing areas, there are so many cracks it is too hard to do them all as above (sometimes you can if there are not too many). So this may be the next way to tackle this problem in one shot.

Grind or sand with 60 to 80 grit sandpaper and get off the gelcoat where the crazing area is. Make sure to go a little further to get all the ends. When done, you should just have the fiberglass below that gelcoat layer. Gelcoat is usually about as thick as an egg shell, so you don't have to go crazy. If you mess-up and gouge a few areas, or take off too much...no worries, just get the area cleared of that gelcoat. This would be a good time to treat or replace any soft core beneath, but we won't go there now.

Clean up the area, get all dust, etc cleaned and take a moistened rag with acetone, (remember to read all instructions before use) and wipe the area well, going further than where you stopped. Tape off the area with blue tape just at the edges, put paper around on that (read boat gelcoat repair)and use a filler to level out the area...meaning fill in the gouges and other low areas. Then use either a wide putty knife to spread it over the area (blue tape to blue tape) or if the repair is wider, (putty knives come really wide) you can use a piece of wood with a good edge. Remember, you have to sand it down anyway. After leveling out the filler, let it harden.

Now sand the area, you may want to use a block sander for larger areas and/or to get the initial heavy stuff off. But as you get closer to the level you want, (about even with the surrounding area when using paint, slightly less when using gelcoat) use wet and dry 220-320 grit wet to get it nice and finish off with 400 and 600 grit. If you mess up at any point, just add some more filler and continue the sanding process so you end up with a smooth level area. This again does not have to be done in one day...it can...but it does not have to.

So now you have that area done...either paint it with a brush, (if very large area, you may want to use a roller and tip it off with a brush) or you can use the spray bottle I talked about in the Boat Gelcoat Repair. Paint you don't sand, but if you are putting gelcoat back, you will be sanding...again read Boat Gelcoat repair about gel coating.

There are many ways to do this repair...this is quick and inexpensive. I always recommend getting it done professionally, and you can find the info & Professionals in the Leftside Menu Bar (we're still growing). Please read all instructions and cautions on the labels...be safe. Also there are many different fillers, some you can make up using the resin and micro-fillers. All are pretty good. Just make sure the supports and good coring are there to get out the flexing, so your job looks juicy for years to come...You'll get better at this too...and Why Knot!

If you would like to know quick ways to repair or replace deck coring, Email me at info@yachtauthority.com or just leave it in a comment below. If you have any other project or repair you're thinking of doing...Let me know.

Tags: Gelcoat,fiberglass,deck coring,boat gelcoat,boat gel coat,powerboat,sailboat,boat gelcoat repair,resin