I have some stress cracks through the hull of my boat which is fibre glass would you use angle grinder?

Question

to chase the fractures out or just sand then repair with multiple slow curing percentage of peroxide mixture trying to let it soak through then sand back to a finish and repair from the inside of hull as well with fibre glass matting with a similar procedure just not sure which is done for best result looking forward to you opinion cheers jp

Answer 1

you just need to repair the gel coat not the fibre glass, because fibre glass move a Little but gel coat doesn't.

you can just look at this link

Answer 2

Do not grind or do any unecessary work on these "stress cracks" unless you have more serious cracking, like thru-hull leaks!  In that case, I would hire a pro or get rid of the boat anyway!  These stress cracks are very common, are only in the gel coat, and you will find more of them every season!  I keep a tube of gel-coat repair on the boat, its just a little tube  meant for these hairline cracks, and I try to keep up with them when I have some spare time.

Answer 3

the cracks are likely only the gelcoat. so no dont use an angle grinder cause you might cut through the glass matt, you can sand off the gel coat with a disc sander if you know what your doing, but an orbital disc is the answer ,, be carefull ..

you should try and fix it so that the water doesnt seep in to the glass matt if its under the water line.

known as "osmosis".

by what you are saying, you think the cracks go right through the hull this is unlikely but if its so , you will have to cut away a large area and feather it back so you can replace all the layers of glass,

fairly technical job and too much to explain here, you should go see a fiberglasser, sometimes its cheaper in the long run if you dont know about f/g

Answer 4

You probably have stress cracks (called superficial cracking) in the gelcoat (the white stuff) of your boat. Many, if not most boats have this happen to them eventually, so there is nothing to worry about when it comes to structural integrity. You can always repair these cracks but they'll show up again in a year or two. Your best bet would be to sand it down by hand, spread some new gelcoat over the area you want to repair, let it dry and then sand it down again so that it is smooth. Then you can just take some buffing compound and buff it out, then use a fine-cut cleaner wax and then a sealant (all used with a rotary buffer) to make it shine like the boat should. Just remember, the cracks will come back eventually. Good Luck!