Plywood hull repair

oscarBravo

Hi guys - mixed results from the first day in the water of my newly-built boat, as the subject title suggests!

Unfortunately we hit some submerged rocks and punctured the hull in a couple of places. An example of the damage, as seen from the inside, is this (click for a closer look):



I guess I have a couple of choices when it comes to repairing it. I can cut out the damaged part, cut a piece of ply to fit the hole, and glass it in; or I can push the dented ply back into shape as well as I can, sand down any protrusions, fill any voids, and glass it over.

Pros and cons of either approach? Or other ideas?

fergal.b

Ouch, not a great first day but an easy fix. I would just pour epoxy resin over it and let it seep in then prop it down with a bit hard plastic over it to leave you with a smooth finish, if you wanted you could add a pice of cloth but I don't think you will need it as when it sets it will be stronger than the ply was in the first place.

Avns1s

Can you countersink something like a gutterbolt (or 4) through it first, then sand down and use epoxy from there?

oscarBravo

fergal.b wrote: »

Ouch, not a great first day but an easy fix. I would just pour epoxy resin over it and let it seep in then prop it down with a bit hard plastic over it to leave you with a smooth finish, if you wanted you could add a pice of cloth but I don't think you will need it as when it sets it will be stronger than the ply was in the first place.

Interesting, cheers. It's holed right through, though - it let a good drop of water in, and if I pour epoxy on it will run through. I'll have a closer look at it later with that approach in mind.

Avns1s wrote: »

Can you countersink something like a gutterbolt (or 4) through it first, then sand down and use epoxy from there?

It's only 6mm ply, though, there's not that much room for countersinking.

fergal.b

oscarBravo wrote: »

Interesting, cheers. It's holed right through, though - it let a good drop of water in, and if I pour epoxy on it will run through. I'll have a closer look at it later with that approach in mind.

If you can prop some 1 or 2mm perspex on the outside to form the shape of the hull and tape around the edge it should seal it up and leave a smooth finish when you take the perspex away after it sets. Make sure the plywood is bone dry before you put the epoxy on it. If you cant prop it drill a hole through the perspex and the hull and through the other bit of perspex on the outside then put a bolt in it and slowly tighten it up till you can see the ply pull back into shape when it sets just remove the bolt and fill the hole.

oscarBravo

This is what she looked like shortly before we pranged her, btw:

fergal.b

Sweet looking boat, just out of interest did you use fiberglass cloth on the hull.

oscarBravo

Nope. The joints are fibreglassed (stitch'n'glue construction), but glassing the hull seemed a step too far for a small project like this.

dnme

Let me at is OB, I'll take care of it for you. Yea I'll take real good care of it!

oscarBravo

dnme wrote: »

Let me at is OB, I'll take care of it for you. Yea I'll take real good care of it!

:eek:

Repairs are complete. We saturated the split ply with resin and wedged it back into place as well as we could. When it had cured, Shane sanded away any ply that was still sitting proud, filled the low spots, then we glassed over the repairs and painted over the glass.

If you go looking for the repairs I'm sure you'll see them, but they're invisible from a few feet away.

Official launch on Sunday at Rosmoney pier in Westport, if all goes to plan.

oscarBravo

oscarBravo wrote: »

...if all goes to plan.

I jinxed it, didn't I.



Sea trials yesterday ended early with the port shroud letting go, with a simultaneous failure of the step - mast and sails in the water. The mast took the partner with it, and it took a chunk of the seat in turn. We limped home with the help of a Civil Defence RIB; they were running exercises at the time.

Repairs started today and are already well underway. She should be back in the water next weekend, weather permitting.

Meanwhile, as of today I'm the proud owner of a Seagull outboard.

fergal.b

Ouch,sorry to see that but at least you all got back to shore safe.

oscarBravo

Repairs are almost complete. Not shown in the photo is the new mast partner and the glass reinforcement on the step. We also had both shrouds re-swaged by a local engineering firm with a hydraulic press, so they should (hopefully!) stay intact next time out.

I fired up the Seagull - first pull, no drama (until I engaged the prop and flooded Shane's garage!). Mighty little engine, can't wait to take 'er for a spin. I reckon we'll do that before we step the mast again; just noodle around the bay with the Seagull for a while, then come back in and bend on the sails.