I took off my fiberglass swim platform to add a tubular one in the future. How should I go about filling the thru-bolt holes in the transom? Also I found some other things under it which I wasn't expecting. There were some what look like nail pops in drywall and also some blisters. The plan is to repair these spots and paint the transom. Any repair tips? Thanks.

The nail pops are caused from too long of screws used to mount something inside the transom. The blisters are from sitting in the water. Have to remover those screws and use shorter ones. The blisters will need to be ground out and filled with an epoxy with filler added to it to thicken. The new finish can be gel, or an epoxy paint-I used Imron on mine with great results and it wont fade. Be aware that if you are leaving the boat in the water the blisters will most likely come back. It may take longer for this to happen with gel.

you can either put a dowel in the holes or back fill with West's 404. Either way do the fill and let cure and then grind back the surface and put a few layers of glass on the outside. One of the biggest mistakes made when doing surface repairs is not fairing back enough. For a half inch hole your going to have to scarf back to roughly the size of a pop (or beer lol) can. Your going to need a few layers of glass to hold back the edge or the original hole, ideally you should scarf back through the entire thickness of the outer skin but its not always practical with hole repairs.

Thanks for the replys. As for the spots that look like nail pops. There isnt any screws on the inside where they are so that is not the issue. As for the blisters the boat is kept on the trailer so it may be from moisture getting under the old swim platform. Dave will I have to grind way back on the blisters too? Also what glass should I use? Just resin or cloth too?

use US composites vinyl ester for everything

http://uscomposites.com/polyesters.html

heres a thread i started a while ago that has essentially all you need to know. scale it back a bit and you should be able to get away with 1708 and some mat.

http://www.offshoreonly.com/forums/f...ash-holes.html

yes the blisters need to be ground back till you hit good glass

first i would v back the through holes b4 you plug them..if the hole is a half inch use like a inch and a quarter drill bit to counter sink the hole then blen it back..

Thanks guys. Ill have to check out your thread Dave. Hopefully there are some repairs on there similar to mibe.