one-fourth of the boat is 'glassed, help?


Since I have nothing but regard for everyone who posts and replies here, I’m hoping your collective expertise can help me with a problem that has developed as I fiberglassed the hull of my Jimmy Skiff.  I’ll spare you the why-details.  

What happened is that:
1.  I laid out the fiberglass over the entire hull
2.  My intention was to start epoxying the top (of the upside down hull), then the transom, then the sides
3.  I started at the back of the boat and was working toward the bow
4.  As some epoxy had run or been scraped over the edge and down the sides, a small bit of the fiberglass on the sides of the boat had been glued on as well.
5.  “The incident” occurred and I had to stop work.

I went back today, now about three weeks later, and cut off the unglued fiberglass from the sides and the bottom of the hull.  I sanded down the edges of what remained.  This left me with a hull that is partially fiberglassed (with just a first coat of epoxy).  Half of the bottom and a little runover onto the sides are in place, as indicated in the diagram of my upside down boat.  This fiberglass has just the initial coat of epoxy, the weave is not filled.



I salvaged a continuous piece of fresh fiberglass that is big enough to cover the transom.  

I once thought that I only needed fiberglass to do the front of the boat.  So in the meantime I already bought 6 yards of 50-inch fiberglass from CLC.  After today I realized that the fiberglass for the sides in the rear of the boat is no good either and has to be discarded.  So I need to fiberglass parts A, B, C, and D in this diagram (B and C on both sides of the boat).  I have a piece on hand for D.



With the 6 yards (18 feet) of 50-inch cloth I have, I can:

Option 1.  Use two overlapping pieces to cover Sections A and B (both sides).  At this point, this would be the most faithful to the manual.  That would leave the Section C’s on each side to do with two more pieces that I would have to buy.  I like this option because it would wrap the front of the hull with two overlapping pieces applied at the same time.  I think I like the strengthening that I believe the overlapping will provide.  I also like the idea of using a continuous piece to tie each side into the bottom in the front half of the boat.  Later I could put a unified second, weave-filling coat of epoxy onto the whole boat.

Option 2.  The sides are much less than 25-inches high (25 being half of 50), so with one long narrow piece on each side I could cover B+C on each side.  That would leave Section A to do with another piece (or two) that I would have to buy.  This option would give each side a continuous piece of fiberglass from the bow to the stern, with some overlap onto the bottom).  I like that too.  I like that it would be an outside complement to the inside fillets.  Later I could put a second unified weave-filling coat of epoxy onto the whole boat.

Option 3.  Forget about my 6-yards.  Buy a lot more new fiberglass and do the whole hull in two pieces plus a transom piece, as per the manual.  Is Option 3 the “best” option overall?  


Hopefully if I went with Option 3, I could leave the existing fiberglass in place?  There are 2-3 square yards already on the boat, and I could live with that bit of extra weight.  This is a 100-lb skiff, not a kayak. 

 Am I right to foresee problems epoxying a new layer of cloth onto an old layer of cured fiberglass whose weave isn’t filled?

Even though I have to buy some more fiberglass regardless, I would like to get what I can out of the 6-yards that I have on hand and go with Option 1 or 2 as long as I’m not compromising seaworthiness.

I would appreciate suggestions or ideas.  If there is anything I need to know about connecting new fiberglass to the piece that is already on I would love to hear that too.

Thank you and bless you all.  


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RE: one-fourth of the boat is 'glassed, help?

m.c.,

The Jimmy Skiff is a small boat with a pretty simple shape, built of 1/4" wood as I recall. As such, it doesn't really need the glass for strength the way a boat with strong curves and thin wood does. I'm building a brand-x sailing dinghy that's right about the same size, also made from 1/4" plywood and the only glass cloth is an optional 6 oz covering on the bottom for abrasion resistance. I also used to own an 11-ft speedboat, same thickness wood, with no glass except the seams.

My point is, as long as you overlap the glass for at least 2", any way that you can piece it will be fine. Option 3 would certainly be the least work to fair, but in terms of strength any of the 3 you describe would work.

As far as putting new cloth over existing cloth, no problem. It's done all the time. Just make sure that there is no blush, that the edges are feathered and give it a very light sanding to get rid of protrusions which could snag the new stuff. Don't bother filling the weave on the existing stuff. That just adds useless weight when the second layer is put on.

You'll be fine,

Laszlo

 

 

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