hull cosmetic repair with cracks in the gelcoat,please help?

I see a lot of threads for inside repair,but not outside hull repair.I bought a 1974 18ft. trihull that has a lot of cracks in the bottom hull.I think it's just paint failure,being 29 years old.I sanded them down with 60 and 80 grit sandpaper,so the cracks are sanded out but now it's not smooth.It's not down to the fiberglass just through the gel coat.My biggest concern is to seal the bottom and build it back up and make it smooth again to accept paint.and is it easier to re gelcoat or paint.If paint is it easier to roll and tip or roll and roll.I don't have a compressor to spray it.But if if spraying is the best option i will buy one.I don't have pics yet but hopefully tomorrow.I've talked to several guys that work at auto body shops and get a different answer from all of them.I work for Finishmaster auto body supply shop so i have access to a lot of supplies but their not cheap.This is a $100.00 boat. so i don't want to put a Porsche paint job on it.Any help would be great,thanks in advance.

Re: hull cosmetic repair with cracks in the gelcoat,please help?

Welcome to iBoats!
You need to wash everything down with a good degreaser. Trisodiumphosphate is a good one. (Get it at lowes) Mix with warm water and scrub the hull. Let dry over nite. Next wash it down with Acetone. Either make your own filler using Poly resin and q-cells or Epoxy and Microballons or buy some 3M Premium Marine filler and fill any dips, gouges, or major scratches. Let dry and sand fair and do another final wash down with Acetone. Check the "Paint Your Boat for Under $100 Bucks" link in my signature below for how to get a great durable inexpensive paint job. All the painting techniques are discussed.

Re: hull cosmetic repair with cracks in the gelcoat,please help?

um....sorry.......forget auto body guys when it comes to gellcoat........just forget it.

i have respect for them.......but unless you are fairing, they cannot help you with a boat. the materials are different. and they dont know.

for example, i subcontract to a guy that is 40 years on the auto body industry....he now owns a boat mechanic shop, with 5 mechanics.
i do all the glass and gellcoat work. he wont touch the stuff....he fixed 10 boats using all his knowlage in auto body. all came back for warranty. thats why he called me. he thinks i am a magician.

for spicer cracks, the gellcoat must be ground off, and the fiberglass looked at, if the glass is cracked, it must be repaired.
only then can a new layer of gellcoat be applied and faired.

in the sticky at the top of the forum.....there is a spider crack "how to"

frisco boater has some how to vids, or click the link in my sig and use the index.

if you are stuck......post pics, we will help you

cheers bud.
oops

Re: hull cosmetic repair with cracks in the gelcoat,please help?

oops! said:

in the sticky at the top of the forum.....there is a spider crack "how to"

Click to expand...

Im pretty certain this is the sticky that oops was talking about.
http://forums.iboats.com/showthread.php?t=320724
Im about to undertake what seems like pretty much the same job. after reading this and asking some questions im not that stressed about it now, all seems rather straight forward

Best of luck mate