Fiberglass repair questions?

[water_rat03]

I am working with a fiberglass V-hull. It has about a footlong crack in the fiberglass where it his the dock or trailer or something. The crack is above the waterline, at the front of the hull on the side.
My questions are, has anyone had any experience repairing this type of damage? How difficult is it to do? Any tips to do this repair correctly would be helpful.

My plan is to cut away an oval around the crack, cutting back far enough to get to un-damaged fiberglass. Then laying fiberglass over the hole. What is the correct way to do this?

Thanks for any advice!

 

[Bifflefan]

Re: Fiberglass repair questions?

Im by far NOT an expert. but i have repaired some cracks in glass.
I make a hole (with a dril bit) at eather end of the crack, this works to stop the crack. then open the crack with a die grinder. then sand down the area around the crack so i hae room to lay in new glass and resin and not create a high spot. then rough up the inside of the hole to give it something to stick to. Start on the inside, with tape in the outside to keep everything in and add glass and resin to the hole boilding it up so as to make the patch at least double the size of the hole on the inside. let that set up. then from the outside rough up the new resin/glass and start the process all onver again. once i have it covered and a little higher than the original surface i let that set up. then just sand and prep for paint.

I have only used this on a racecar panel and not a boat. but this this was tought to me by a body and paint guy, and trial and error.

Good luck in your endever.

 

[ondarvr]

Re: Fiberglass repair questions?

Don't cut a hole, that'll just make it more difficult.

If you can get to the inside, then you can put several layers of glass there leaving more of a cosmetic repair on the outside.

You need to grind all surfaces before glassing. After putting glass on the inside, grind and area an inch or so larger than the crack on the outside, build it up with glass and sand it to match the surrounding area, then gel coat or paint it.

If you can't get to the inside, you just need to do a larger, stronger repair on the outside. This means grinding deeper and a slightly larger area.

 

[water_rat03]

Re: Fiberglass repair questions?

That makes a lot of sense. On the outside grind it down low enough that the patch won't be raised and look like a bandaid?
Should I be concerned about the fiberglass being weakened around the crack? I am not sure what happened to it but it looks like it hit the dock hard.
Thanks for the information.

 

[Bifflefan]

Re: Fiberglass repair questions?

I dint mean make the hole bigger so to speak, just a little biffer to get out the damaged glass.
After rereading my post i can see where that might have been taken like that.