Fixing a screw hole in fiberglass.

reelfishin · Post by **reelfishin** » Mon Oct 11, 2010 5:25 pm

I was wondering the other day about how to fix a screw hole in fiberglass. I am not talking about patching it I mean making it useable where water cannot get into the boat. I know you can epoxy and then caulk. I thought about putting a plastic dowel or something in and epoxing it in place. Then drive the screw into the dowel. Anyone have any better ideas on how to keep a sealed hull dry? You all know people mount things.

prowlersfish · Post by **prowlersfish** » Mon Oct 11, 2010 8:06 pm

Above or below the water line ?

rbcool · Post by **rbcool** » Mon Oct 11, 2010 8:19 pm

How big a hole ??

Danny Bailey · Post by **Danny Bailey** » Mon Oct 11, 2010 8:21 pm

If it's below the waterline I use 5200 or polysulfide caulk with a backing board inside the hull. If above the waterline it depends on the application.

alexander38 · Post by **alexander38** » Tue Oct 12, 2010 5:48 am

in sayin this i assume it's a small screw hole, i'd stick with the epoxy way and a backer, i've never seen a yard go with a dowel myself i'd worry about the dowel pullin out under stress.

reelfishin · Post by **reelfishin** » Tue Oct 12, 2010 7:16 am

The holes are above the water line. Putting a back on the screw hole would be hard to do because you cannot get to the hole from the inside.
Here is what happened , A cover was installed on the boat and it is installed on a rain channel. The screws go through the rain channel. It really was a poor design when they did that. Any water in the channel goes through to the inside of the boat.
Here is what I did , I bought a roll of the corner bath caulk that you press into place. It has a plastic top and a sticky bottom. I cleaned the holes and placed a short piece over each hole. I sat the lid back on and put the screws back into the holes. I also put some caulk on the place where the screws would go through the plastic. I think this will help keep the water out and still let the water run around the strips.
That is why I was looking for a better way to do it. What I need is something that would screw in that would be water tight and still let me put a screw into from the cover.

Peter · Post by **Peter** » Tue Oct 12, 2010 4:50 pm

mix up your epoxy and add some strand filler or micro ballons ,enough to mix to the consistancy of peanut butter.Then load a 10 cc syringe with the epoxy [I use tongue depressors,..will need several syringes cause they plug up].With the hole dry [hair drier if its a crappy day] use the syringe to shoot the epoxy in the hole.when it's dry,drill your pilot hole for your new screw.ALWAYS coat the threads with silicone to stop water intrusion,or in several years you'll be doing it again.

westsystems has several pubs that are easy to read...(idiots guide to fiberglass repair)

rossjo · Post by **rossjo** » Tue Oct 12, 2010 5:24 pm

Sounds good except for "ALWAYS coat the threads with silicone".

Silicone doesn't stick to anything and won't last - use 3M 5200 marine sealant (polyurethane), and it will stay sealed!

Peter · Post by **Peter** » Tue Oct 12, 2010 5:45 pm

marine silicone...not bathroom stuff...

rbcool · Post by **rbcool** » Tue Oct 12, 2010 5:56 pm

Maybe I'm missing something ; are the holes too big for a screw? In the past when a customer didn't want to incur fiberglass costs, I just loaded up a screw with 5200, screwed it in, and after it dried took a new razor blade and carefully trimmed the excess away. Will last for many years. Just a thought if I'm getting this right.

reelfishin · Post by **reelfishin** » Tue Oct 12, 2010 7:09 pm

The problem I have with silicone is water will get under it over time. I have seen it happen on our boat when we use silicone. I agree I should have done the threads but I figure the caulk on the tape and the screw running through the caulk is doing the same thing. Probably better to do the threads. If I take one apart I will get a picture of how it was done.
The reason for asking was to have something that was removable and still sealead. In other words the screw hole would not be all the way through the hull. The hole would not be open to the hull with the screw out.

foofer b · Post by **foofer b** » Tue Oct 12, 2010 8:21 pm

Use the handy man's secret weapon- Duct Tape!!!

reelfishin · Post by **reelfishin** » Wed Oct 13, 2010 2:26 pm

Duct tape, now that is a cure all for everything. Speaking of duct tape I just got a email where a group of people protested some bikers wearing leather jackets. It seems they did not like them wearing leather. One of the protesters ended up duct taped to a tree about 4 feet off the ground. I thought it was quite funny.
You are right duct tape handles everything.

reelfishin · Post by **reelfishin** » Wed Oct 13, 2010 2:27 pm

Anyway thanks for all the ideas and replys. You all are the best.