sparky24

great idea, dont have a big enough compressor

sparky24

OK so it turns out that i am dealing with gel coat here, the thought didnt even cross my mind (idiot lol) So what is the proper way to prep for retabbing my stringers with 17 oz biaxial? it is impossible to get all the gelcoat out of the roving - once the gelcoat is gone, so is the roving. What is the normal repair in this situation?

Someone told me to do the best i can to get the gelcoat out and then use 1.5 mat before i lay the biax to even out the dimples???

Help appreciated!

glassdave

iTrader: (1)

Can you post pics? Sounds like there is only a single layer of roving?

When using bi-ax you dont need to put down a layer of ounce and a half mat. Just make sure you put the mat side down when laying the bi ax in. When re tabbing its really important to do all you work with a grinder in 36 grit and make sure you keep it moving to keep surface well blended.

sparky24

Pics in this thread: http://forums.iboats.com/showthread....24#post3982924

There was delamination on both sides of the vee about half way up from the pad to the stringers and it went under the tabbing some, so i figured it was a good idea to retab the whole thing seeing as after drilling the stringers and upsizing the holes for the mounts they seemed really solid. I think the delamination was from water getting into stress cracks in the mat, because in the areas where there was roving there were really no stress cracks it was only in the thinner areas of the hull where it was thing cloth and mat only. So i grinded all the cracks and delamination out.

I totally get that i dont need mat with epoxy but people have been telling me to use mat before i put on my 17 oz biaxial (not 1708 with mat) in order to even out the dimples in the roving.

Oh and yep on the stringers it is only one layer of very heavy roving, so once i get all the gelcoat out there is practically nothing left, i actually did a test area to see how much would be left and i litterally grinded down to the point that i could see bare wood, its counterproductive. im not afraid to break out the grinder as you can see in the pics lol, i just cant see the point in grinding everything that is there off, but at the same time its such a structural area that i am uncomfortable leaving the gelcoat in there.

glassdave

iTrader: (1)

oops forgot you were using epoxy. No mat should ever be used with any epoxy system for any reason and prep is crucial. In the pics it looks plenty well ground enough in the open areas. Some older laminations tend to carry an opaque-ness through the fibers and it looks like pale white checkers. Are you sure its not that that you are mistaking for gel? Kinda looks like wood grain but has a pattern.

sparky24

ok so you are saying that it doesnt look like gel? Just paint?

ok just ground the stringers, bulkhead, and transom for new tabbing, finishing up with the die grinder in the corners and hard to get areas... after i go bolt my compressor down (keeps walking into the wall)