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Kevlar SKid plate adhesive?

Posted: Fri Sep 04, 2009 3:13 pm
by mtnfir
Hey all,
JUst got of the harmonygear website after looking at their kevlar skidplates ($19.00) . THe price jumps considerably when you get the kit which includes adhesive and sandpapaper and even more when you get the kit for royalex. THere have got to be some other options. I've got an outrage X and want to add skidplates to it because it is finally starting to show some wear. Are there any non-proprietary resins, adheasives, whatever that I can use to successfully install the 19 dollar skidplates?
thanks

Posted: Fri Sep 04, 2009 3:21 pm
by PAC
I suggest using the search functionality on the site for "skidplates", "skid plates", "bow repairs", etc.
There are a couple good posts in there that might give you some ideas as to a "home grown" solution.
It might not be cheaper in the long run (finding materials, labor, etc.) but worth reading to get what you want. Good luck!

Posted: Fri Sep 04, 2009 3:27 pm
by ezwater
If you were very careful, you might be able to do them with $50 worth of West G-flex resin.

An alternative is to use S-glass or E-glass, bias cut, about four concentric layers, largest layer goes first and so on down, using G-flex or (for easier soaking), regular West 105/205 resin. You get a much lower profile, lighter skid plate with good compression strength.

Or, you could try melting ABS in acetone and painting on a bunch of layers.

Thing about Kevlar felt skid plates is they are a convenience product. They are easy to apply, but Kevlar felt doesn't make a particularly strong outside layer for a boat. Kevlar cloth is a little better, but not as good as S-glass or even E-glass.

Posted: Fri Sep 04, 2009 10:03 pm
by Eric Nyre
Go to your local fiberglass shop and pick up some S-glass for the skidplates. It will be cheaper than Kevlar felts, it will wear better, and you can make it somewhat smooth so that you don't grab when going over rocks.

Kevlar felt is easy but isn't the best choice for skidplates.

G-flex also wouldn't be my choice for resin. Expensive and too sticky/ flexy. Great for repairs, but you want something harder like basic 105 when abrasion is the main issue.

As noted above, search the board and you'll come across many good suggestions that will outperform the Kevlar felts for less $$$.

Posted: Fri Sep 04, 2009 10:49 pm
by milkman
I haven't tried it yet, but I've just ordered the Rec Repair skid plates. I found them on Amazon. I was impressed with how bomber their patches were when I used them on a whitewater canoe, so I figure the skid plates must be tough as well.

You can learn more about the skid plates at: http://www.recrepair.com/skid_plates.html

Like I said, I haven't tried them yet, so no direct experience. But I've never been happy with kevlar skid plates, so it's time to try something new.

Posted: Mon Sep 07, 2009 9:49 pm
by ezwater
Eric, do you really find S-glass so easy to obtain? I have to order it in.

As for using G-flex with S-glass, I am using a batch of S-glass from johnrsweet.com that is very tightly woven. Whether I use G-flex resin or West 105/205 will make no difference as to the resistance to being drug over rough surfaces, because with either resin, the S-glass fibers are quickly going to be exposed at the surface. S-glass is very hard and does not wear down easily.

Although it's called G-flex, this new resin is not gummy or rubbery when it has set. It is quite hard. It is probably exceptionally compatible with Kevlar, but there should be no problem with S-glass.

Posted: Tue Sep 08, 2009 7:29 pm
by Todhunter
ezwater - S-glass can be obtained if you make a short drive down to Aircraft Spruce in Peachtree City - they have all sorts of West products and lots of different types of glass cloth in stock.

Posted: Tue Sep 08, 2009 11:38 pm
by ezwater
Thanks for the info. I hope they have good stock turnover, because I've always been a bit spooked by John Sweet's statement that the coating on glass cloth doesn't age well, so that resin may not adhere as strongly after several years.

Posted: Wed Sep 09, 2009 11:58 am
by Todhunter
My experience tells me that the turnover is pretty good. Aircraft Spruce is a nation-wide catalog, with only two warehouses - the one in PTC and there is one in California. They are supplying the general aviation market, and there is a lot of glass on GA aircraft, even mostly metal ones like I am building, so I can almost guarantee that you won't be getting cloth that is years old. You can always ask them, though. If you go down there, you'll probably talk to Tim at the counter - great, honest, but goofy guy.

Rec Repair Skid Plates

Posted: Wed Sep 09, 2009 1:41 pm
by Al Donaldson
EZ:

I have installed quite a few Rec Repair skid plates, and have found that:

1) They take a bit more time to form than is suggested in the literature -- no worry, they are worth the effort.

2) The thickened G-Flex adhesive is absolutely great for attaching them.

3) They do drag a bit harder over sharp surfaces than a smooth S-glass patch, but they don't wear anything like as fast.

4) After a year or so, they take on a porous look -- I have no idea what is going on there, but it doesn't seem to hurt the strength or abrasion resistance.

5) It pays to take your time with the forming process: any mismatch with the boat contour will want to be filled with epoxy later. (Although I intentionally left ab oat with voids in the adhesive out in the Iowa winter last year to see if the voids would cause cracking or loss of adhesion when filled with water and then frozen, and that did not happen.)

6) Be gentle with your heat gun -- if the plate starts to "bubble" during the forming process, it got too hot. Press out the bubbles immediately and continue with the forming process: the bubbling does not seem to effect the plate's strength or later adhesion.

HTH

al

Posted: Wed Sep 09, 2009 2:42 pm
by ezwater
Sounds like a great alternative to Kevlar felt. I still have Kydex sheet I bought decades ago to skid-plate a Tripper using the same heat form and epoxy method. But I ended up doing glass skid plates instead.

Went through Iowa about three weeks ago and thought, "I wish I knew somebody in eastern Iowa who could tell me what I might run while I'm here....." DesMoine was too low NW of that city, the Skunk looked like a chocolate mess near the Mississippi, and I knew the Upper Iowa was too low.

But now I have a nephew starting at Luther College in Dacula, so when the Upper Iowa runs, I can drive up there and get him to drive shuttle for me.

Iowa Paddling (WAY off topic!)

Posted: Wed Sep 09, 2009 3:02 pm
by Al Donaldson
EZ:

Give a call if you head this way. Whitewater is almost nonexistent in Iowa, save for a few park and play spots, but we have some small rivers and creeks that will make boaters work a bit to get through "clean."

The Volga, Yellow, Upper Turkey and Little Turkey Rivers are much better paddling than the Upper Iowa and are not ever swarming with drunken renal paddlers.

Regards,

al