OT Repair

I have an OT Discovery and Tripper (Royalex) which need some minor “scratch repairs” on the outside of the hull.

1. Any advice here on what to use?

2. Was also looking to add some Kevlar strips for more protection.



Links and/or sources for these materials is appreciated along with some “how-to” advice.



Thank you.


I’ll skip comment on the Discovery,
because I regard poly canoes as disposable products not worth keeping pretty.



I did own an OT Tripper for a number of years, and it was a great canoe. I stored it in the shade, and otherwise I did not bother about the hull surface, unless it wore through the vinyl topcoat in spots, exposing the ABS structural layer to UV damage. Then I would paint over the ABS as necessary. Not pretty, but ugly boats are less likely to get stolen.



Why do you ask about Kevlar? Are you thinking about getting those ugly, heavy, stiff Kevlar felt skid plates that many consider to look fashionable? Easy to put on, but doesn’t make the boat work any better. Wait until the ends are damaged underneath, and then come back and ask how to do glass skid plates.



Kevlar is not an “outside” repair cloth. Glass is better, especially S-glass. Dynel can be used for wear patches, but isn’t any stronger than ordinary glass.



Trippers are very strong, and heavy, and are not in need of prophylactic Kevlar, glass, or other patches, inside or outside. If you have to patch inside, Kevlar is good. If you have to patch outside, S-glass is good. If you want to enjoy canoeing, go canoeing, and don’t worry about problems in advance, especially for two boats that were designed to be thumped, scratched, scraped, etc. To worry about those things, go get some 40 pound ultralight Kevlar thing.

Discovery repair
Your Discovery canoe is made out of polyethylene. If you have deep scratches that you feel need attention you can probably fill them in somewhat by melting/welding polyethylene into them.



To do this you need some polyethylene “welding rod” (preferably color matched), a heat source, and something flat like a putty knife or paint scraper. A heat gun will probably work as a heat source. You need to carefully heat the damaged hull and the welding rod and work the molten polyethylene into the scratch with your tool.



Conventional epoxies and other adhesives like methacrylates and urethane adhesives will work on Royalex (which is basically vinyl-coated ABS) but won’t bond well to polyethylene so you can’t use those for cloth repairs whether they are done with aramid (Kevlar), Dynel, fiberglass, or other fabrics.



West System G Flex epoxy will bond to polyethylene but only if you prepare the hull surface carefully prior to application. This requires through cleaning and then “flame oxidizing” the hull by briefly passing the tip of the inner blue cone of a hand-held propane torch over the surface to which the epoxy is to be applied.



I agree with g2d that Kevlar felt is not the best material to use for abrasion plates and that they need not be applied over undamaged hull.