Laying Fibreglass

[Biggles]

My hull has been stripped of all its old paint and underneath I have found some repairs.

I'm not too bothered its old but seaworthy.

What I would like some advice on is some fine lines in the gelcoat.

Although these don't move and therefore seem to be only in the gelcoat and not the glass underneath. I would like to seal them from water penetration now that the protective paint has been removed. I'm not too bothered what the final repair looks like as long as I get another year out of the boat.

What I intend to do is glass over the fine lines with Fibre glass tape to seal them from seawater.

I intend to use 2.5cm tape to overlap each other and then one final piece to cover this. In effect covering the fine lines with three layers of tape. Will this be enough ? or is it too much.

I am then going to paint over it with Brightside. I don't think this will last for ever and so will then Anti Foul it if the Bright side doesn't last.

Anybody's experiences would be welcome.

[boatster_sr4]

Take pics if you can. Most likely those fine line cracks are just cracks in the gelcoat. Nothing to be worried about. I have cracks on the gelcoat of my rib on the outside of the hull on the chines. I used to worry about it but after some reading around was assured that nothing structural was in danger.

[Biggles]

Hi Mate,

My cracks are along the chines as well. I just want to cover them over to stop any water at all getting to the glass.

I'm not too bothered what it looks like so long as its sealed.

Maybe I can get away with one layer of tape then.

[jwalker]

Take an angle grinder along them, just enough to V them out, and fill them with gel coat. After it's hardened, sand them smooth.

[Biggles]

Hi J,

I've read all sorts of conflicting things about Gelcoat on this forum.

If I angle grind the cracks out and then fill them with gelcoat do I need to cover them with something to make the Gelcoat harden. I actually own a Angle Grinder. And I want to learn about boats.

Also because my hull is orange, and I couldn't find orange pigment in my local chandlers, Aladins Cave, Hamble, can I add a little bit of orange paint to colour the Gelcoat.

Forgive my ignorance but what sort of consistency is Gelcoat. Is it like filler or is it like a paint ? I saw small tins of Gelcoat in the chandlers and also small tubes of pigment. But as always not the colour I wanted.

Can I apply it then cover the whole area with plastic sheeting to make it harden

Many thanks in advance.

[boatster_sr4]

What Jwalker suggests sounds like a good idea. I would probably want to get a perfect match on the gelcoat pigment first though. For my situation I would only do it if I could meet that prerequisite. Otherwise I'm certain the end result would look worse than the current hairline cracks.

I assume you trailer your boat. If thats the case water intrusion damage should not occur I would imagine.

[boatster_sr4]

Originally Posted by Biggles

Hi J,

I've read all sorts of conflicting things about Gelcoat on this forum.

If I angle grind the cracks out and then fill them with gelcoat do I need to cover them with something to make the Gelcoat harden. I actually own a Angle Grinder. And I want to learn about boats.

Also because my hull is orange, and I couldn't find orange pigment in my local chandlers, Aladins Cave, Hamble, can I add a little bit of orange paint to colour the Gelcoat.

Forgive my ignorance but what sort of consistency is Gelcoat. Is it like filler or is it like a paint ? I saw small tins of Gelcoat in the chandlers and also small tubes of pigment. But as always not the colour I wanted.

Can I apply it then cover the whole area with plastic sheeting to make it harden

Many thanks in advance.

Gelcoat is just polyester resin. You can use a thick celophane to keep the resin from air while it cures, this is called Vacuum bagging. Or you can put a wax addative in the polyester resin that makes it cure non sticky. I would suggest maybe going to a surfboard or other poly resin glassing manufacturer and see if they can color match you a pint of resin. Mixing paint into the resin will NOT work. You will just get a milky translucent mix. I'm no expert but I've messed around enough to know some.

EDIT: You add catalyist to make polyester resin harden. The issue after that is getting it to cure non sticky. Vacuum bagging and adding wax are ways to seal off the curing resin from air thus it cures hard and non sticky. If it cures sticky you'll go through hell trying to sand it down. It'll be an bigger uglier mess than before.

[Biggles]

Hi,

Yes I trailer my boat. When its in the water it will probably be for about 6 hours at a time.

Don't you think that will let water in ?

The reason I am concerned is for the following.

Today at work I was in a fibreglass building. Around one of the doors was a fine crack. This could be bent by hand, whereas the area without the crack couldn't. The Gelcoat seems to provide strength and it must also provide a waterproof barrier. Surely the presence of any crack would allow water through to the glass. Then once its got to the glass its only a matter of time before the glass falls to bits.

Thats why I am concerned and thats why I would like to do something to stop the water getting in now even if it doesn't look to good.

[Biggles]

Originally Posted by boatster_sr4

Gelcoat is just polyester resin. You can use a thick celophane to keep the resin from air while it cures, this is called Vacuum bagging. Or you can put a wax addative in the polyester resin that makes it cure non sticky. I would suggest maybe going to a surfboard or other poly resin glassing manufacturer and see if they can color match you a pint of resin. Mixing paint into the resin will NOT work. You will just get a milky translucent mix. I'm no expert but I've messed around enough to know some.

Okay so I won't be mixing paint in it then.

Thanks for that bit of experience.

[Biggles]

Can anyone in the Southampton/Basingstoke/Portsmouth area recomend anyone to mix me up some Orange Gelcoat in a bottle that I can get home and then use over the course of a few days ???