Repairing ply / epoxy damage

[ausnp84]

Hey guys,

In the process or buying a boat and the inner side of both bows requires some fixing (a pontoon got wedged under the boat during a storm last year).

I’ve been down to the boat, moisture checked it and can confirm it’s pretty much the top layer of glass that’s been heavily abraded (port side) with the starboard side having similar damage but slightly deeper (into the first layer of ply).

Would I be correct in thinking the correct repair procedure would be to:

- Sand the damaged area to remove any damaged fibreglass / ply,
- Let any moisture dry out completely,
- Cover the whole area in epoxy, then layer on a couple of layers of fibreglass cloth (biax? Standard CSM)?
- Cover in peel ply, let it cure off for a week, sand then re-prime with a barrier coat and repaint?

N

[Chotu]

You’re good. Just make sure to create a very slow transition when sanding out the damage, so the new fiberglass overlaps the original (and undamaged) fiberglass. Makes it easier to fair and allows the glass to grab the other glass better. It’s a scarps joint in the glass you want to create.

No need at all for peep ply in your process since you’re sanding right after it.

[ausnp84]

Originally Posted by Chotu

You’re good. Just make sure to create a very slow transition when sanding out the damage, so the new fiberglass overlaps the original (and undamaged) fiberglass. Makes it easier to fair and allows the glass to grab the other glass better. It’s a scarps joint in the glass you want to create.

No need at all for peep ply in your process since you’re sanding right after it.

Thanks mate. And biax cloth or CSM?

N

[Chotu]

Originally Posted by ausnp84

Thanks mate. And biax cloth or CSM?

N

Biax for sure. CSM doesn’t have much of a place with epoxy.

[tkeithlu]

Cloth is stronger. Lightly sand with rather coarse paper to get the scratches that will let the soup really grab.

[ausnp84]

Thanks guys. I was thinking of a 300 or 600 gsm cloth as it’s a non-structural (ie. not a bulkhead) repair, but I’d still like some toughness in that area, and then bonded altogether with epoxy.

N

[Clivevon]

Dont use CSM with epoxy unless it is the type of CSM designed to use with epoxy. Most CSM should be used with polyester resin & epoxy will not dissolve the powder binding so you wont get a good bond. Dont Ask me how i know ...