advice sought on repairing fibreglass seams

[ruth]

Hi
I need to repair selected fibreglass seams on a delapidated plywood dinghy (Mirror design) I inherited after my brother put a hole in the deck. The paint work is in extremely poor condition, so I have sanded everything back, and in the process found that the fibreglass was loose or flaky along some of the seams in the cockpit and deck. I peeled off what I could easily remove....

Do I need to completely remove all traces of the original tape and resin, in order to do an effective repair? If so how do I get it off without damaging the plywood ? this is my first ever attempt at repairing a boat, Im daunted but enthusiastic.
Cheers R

[Pipex]

What you are attempting to do is very simple. You need to keep a cool head but should be no problem for you to achieve a relatively decent result.

My experience with mirrors is much the same. They all seem to look like clapped out rusty sardine tins which is a shame because they are lovely boats. Great restoation project, although sails maybe expensive.

I will try to give you some of my info. for you to make some good decisions...

Have a brief look at the structure of the boat and see why the fibrglass was there. Is it structural? Do you think that much stress will be in this area.

Look at the thickness of glass you have removed and its structure. Make decisions based on what you think this fibreglass was for why it was put there etc...

SAND back the matt/resin where it has started to come off the wood (delaminate). You may be able to use a scraper but sanding is better as you will remove less wood, depends on the size of area involved and your athletic ability!!

Get yourself some 400-600gsm pb csm (400 to 600grams/sq.metre powder bound chopped strand matt) and some Polyester resin. Epoxy is better but is very expensive, Polyester is fine. A kit from Car/boat shop will do, SP systems do some good kits. Follow the chemistry exactly, Follow temperature guidelines exactly!!

Get yourself normal paintbrush (not plastic bristles, hair). and a mini paint roller. Mix up the resin and paint thin layer over wood. Slap the matt on and use roller to sparingly put more resin on top so the matt looks "wet" (but not dripping!). It doesnt matter if some matt sticks out "dry" around the edge because you can sand this off later...

Sand back once dry, maybe put more matt/resin on depending on the finish needed. If youre painting would reccommend taking back to at least 800 with wet and dry if you can 1500-2000 to get best finish.

Good luck, read lots be careful with temperatures and measuring hardener/catalyst: resin ratios. Its very simple!

Hope this helps!

[ruth]

Thanks, I appreciate the quick response. Looks like I have alot more sanding to do.....

[Pipex]

You are going to get good hands!!! just like me.