Repairing seams on old Klepper hull?

[overland]

I pulled out my old Klepper Aerius II today to ponder its seams. These are the seams on the upper part of the hull, attaching Hypalon to Hypalon. I suppose they used cotton, and the seams are coming apart in a few places. The hull's too old to send it off to Long Haul for repair. It wouldn't be worth it. Is there some way I can do it myself? Will Aquaseal hold the seam together? Is there some way I could sew it myself, or have it sewn locally? It's pretty thick stuff.

[chrstjrn]

I would suggest gluing a patch over it, but gluing hypalon to hypalon is very difficult (one of the many advantages of PVC that is cited by it promoters).

Before you get the idea that I am, myself, overly- pro-PVC: I own a Hypalon boat, have two rubber-hulled restoration projects, and have sold both of my PVC-hulled boats.

[overland]

That's a really interesting suggestion I hadn't thought about. The seam is pretty thick and wide. The Hypalon is overlapped about an inch and fastened with a single line of stitching, but there's some kind of sealant tape on the inside too, and some kind of adhesive. I'm just guessing. You're suggesting I cover the whole thing with a Hypalon strip on the outside of the hull? maybe 2-3 inches wide? It would add weight but might work. Maybe what I should do is try to seal the seam, where it's parted, with aquaseal--or is there a better adhesive for hypalon? And then it that doesn't work, use the strip you suggest. I hate to give up on the hull when it still seems to have some life in it. Whether it's good enough for my Alaska trip is another question ...

[chrstjrn]

Someone was recently advertising an expedition hull over on Bagboater.

I'm not sure my idea of glueing a strip over it is a good one-- it might look hideous, which would be a bummer. Malcolm mentioned some super-strong adhesive that might work, a couple of weeks ago (here) in the repair section.

Maybe the best way is getting the proper equipment from Sailrite and re-doing the stitching by hand-- depending on whether it is in an area that you can turn inside out (i.e. not too close to the bow).

[overland]

What kind of super adhesive are you suggesting? Also, can something that thick--two layers of Hypalon, be sewn by hand? As it happens, the stitching is failing in the middle of the boat, not toward the ends. I would be glad to give anything a try--adhesive or sewing--or both. As for a patch, it would be the same as putting on a keel strip, I suppose.

[chrstjrn]

Look into the process of sewing sails. You will need a "palm", special needles, special thread... Sailrite is one place you can find those things, and I'm sure there are others (probably Duckworks...). I'll be interested to follow, so I hope you post photos

[overland]

I suspect it's more like sewing leather than sewing sails, but I'll look into it. It no doubt can be done. It might just take a long time.

[chrstjrn]

Dyson talks about it in Baidarka, to some extent. I haven't done it, so I can't say-- but it seems to me that it could be done.

[overland]

I know I could send the hull to the folks at Long Haul Kayaks, who would sew up the seam for me. But it would cost a lot and maybe isn't worth it. Aren't there local businesses that might have heavy duty machines that could stitch a seam in rubber coated fabric? Any suggestions. The seam of course is on the side of the hull, just a few inches below where the canvas deck is attached. (That seam seems fine.)

[chrstjrn]

Check with a sailmaker.

[idc]

I know I could send the hull to the folks at Long Haul Kayaks, who would sew up the seam for me. But it would cost a lot and maybe isn't worth it. Aren't there local businesses that might have heavy duty machines that could stitch a seam in rubber coated fabric? Any suggestions. The seam of course is on the side of the hull, just a few inches below where the canvas deck is attached. (That seam seems fine.)

Wouldn't the old fashioned cobbler have had an industrial sewing machine capable of sewing thick rubber soles to thick leather? I'd have thought those old machines would do the job. (Last time I visited the cobbler though he simply told me to chuck my comfy old shoes and buy some new ones off him so perhaps they don't bother with the equipment any more--might be available via ebay, though, if you look for vintage sewing machines.)

[chrstjrn]

That is an excellent thought-- a cobbler. There was a shoe repair guy in the last place where I lived-- a Lebanese immigrant. I think he would have been glad to try to help, and his machines would certainly be able to stitch any number of layers of our hulls.

[overland]

So I called a sailmaker in Chicago, also a small company that works with marine canvas. I explained the job and sent them pictures, and both said they could do it. I don't know how much it will cost. Here's my question. How can I waterproof the seam when they're done? Lather on some seam sealer like on a tent seam? Otherwise it will leak, won't it? It looks to me like Klepper had a narrow strip about an inch wide that it glued on over the top of the seam on the inside. Probably they also put some kind of glue in between the two layers of fabric they were stitching. Maybe before I bring the hull in I should "fix" the seam with aquaseal or shoe goo or something simliar so that when they sew it there will be a barrier against water in the middle of the seam.
Suggestions?

[overland]

Here's another possibility. NRS sells 2.5 inch wide gray hypalon strips--they call it seam tape--to reinforce seams on inflatable rafts. Why couldn't I just glue this over the seam and not worry about resewing, etc. It would be cheaper and I wouldn't have to worry about leakage. Maybe not the most elegant solution, but wouldn't it work?

[chrstjrn]

I don't think it would leak much. As if the (cotton) canvas were strictly waterproof in the first place...? This is really good news. Get it stitched professionally and see how it works-- I'll bet you won't look back.