Bonding D-Rings to Kevlar

I want to bond the vinyl backed, 2" D-Rings that Northwater Rescue sells into a kevlar canoe.



I’ve used their vinyl-tec 2000 product, which I’m pretty sure is the same thing as vynabond, and am confident that will work, though maybe not quite as well on kevlar.



I hear I can use epoxy, like the West System stuff, as well.



Any experience with epoxy-ing vinyl to kevlar? Will the epoxy be stronger? I know the epoxy will be dern-near impossible to remove while the vinyl cement will come out with a heat gun, but other than that, is the epoxy a better bet?



Thanks

Not sure …but
I don’t think epoxy sticks to vinyl - you can use PVC sheets to smooth an epoxy surface without it sticking.



You can glass D-rings right to kevlar with epoxy and it will hold quite well. Have done this in surf kayaks several times.

What sort?
When you say glass d-rings right to kevlar, do you mean a d-ring with a bit of webbing through it, or just stick the D ring in position and put fiberglass cloth through and around it? I prefer the ring have some flexibility to lie flat when not needed. However, I suppose I could find a way (wrap it in tape or waxed paper or wax first, then glass over so the epoxy would form around the ring, but not actually contact the metal?)



Good to know the epoxy on vinyl isn’t the best choice.

I use West G-flex epoxy to attach
vinyl d-ring patches to the inside of Kevlar boats. It works very well. You need to put some poly film over the work while it hardens, and then some springy foam, and then weight the foam to push the patch down. The only prep is to clean the Kevlar surface, sand lightly, and clean the patch underside. You can lightly sand the underside of the patch to let the epoxy get a bite on some of the fibers in the patch.



The notion of attaching patches to the inside of a Kevlar boat using Vynabond or similar is just a joke. Vynabond has little “gluey” content. It’s mostly solvent, intended to soften TWO (2) vinyl surfaces so they will contact cement together. That solvent is unlikely to have any effect on the resin of a composite boat, whether it’s vinylester or epoxy. Anyone who has gotten patches to stick to Kevlar composite with Vynabond should consider themselves lucky----so far. Don’t use something that should not, by its very nature, work at all.



Because I’ve seen Vynabonded d-ring patches fail spontaneously after many years, I also use G-flex to attach patches to the vinyl interior of Royalex boats. G-flex has outstanding stick-to-it-iveness.

See below. Epoxy glues to vinyl
just fine.

Of course
Now that I think about it, I have epoxied to Royalex boats, and of course the outer layer of that is vinyl.



Do you think it’s worth buying G-Flex if I have lots of the basic West system 105 on hand?



Thanks again!

If using epoxy / glass all you have to
do with the D rings is wax them a couple times … The epoxy will not stick.

I use Marine Goop
I found it bonds the patches better than epoxy or regular contact cement.



Jack L

Yes it does…
Ah’s got d-rings wit backin’ plates epoxied onta de vinyl skin on Royalex dat ah’ put on 25 years ago an’ still holdin’ strong…



Epoxy sticks ta vinyl, Pilgrim…



FE

West 105/205 will work. I.d recommend
a thickener so it doesn’t run out from under the patch during hardening. But you can get 4 oz G-flex portions for less than $20, and it can be more economical, because with a 1/1 mix ratio by eye, you can make a smaller batch per job than you can with the smallest size 105/205 pumps.

G-Flex it is . . .
OK, I’m sold. I’ll buy the G-flex and maybe some extra for my repair kit (a good repair kit is like my talisman against catastrophe).



However, the more I think about it, the more it seems that there are a few right answers. I just checked the D rings I vinyl cemented to my Hellman canoe last year and they seem really solid. Obviously, the epoxy will be even stronger, so it seems that everyone wins!



Thanks for the help, everyone.