Defuzzing Kevlar Fibers

Yep, that was a big rock!

So now I have an educational opportunity. I have a small 1"x1/4" chipped off gel coat area on the hull of one of my kayaks and several Kevlar fibers of a carbon/kevlar blend that are broken and fuzzed. Trimmed down with sharp scissors as best as possible but what’s the next step in getting rid of the unruly ends?

Anyone with first hand experience?

See you on the water,


The River Connection, Inc.

Hyde Park, NY

I have patched interior with a Kevlar
patch… apply resin to broken area first, lay patch in, dab more resin through patch… at this point you worry about those ends of kevlar that you think will be a porcupine.

Apply a Peel Ply layer… Dab with more resin.

Let dry… Peel off Peel Ply. Woila. Obedient Kevlar with the unruly ends nicely controlled so they wont knife you… they kind of self fair into the resin.

Other side.
Good advice and process. I’ll keep that filed for when I have interior issues. The area that’s de-gelcoated and fuzzed is on the exterior. Gel coat’s the easy part. Just need to know of any tricks to deal with fuzz ends to keep from making some very funky looking gel coat finish.

no experience with the other side
so I’ll watch too.

What has always worked for me
many times in the past.

Once you have it all trimmed like you do just put some epoxy on it, and tape, (nice and tight) a piece of stiff overhead projector film or looseleaf page protector over it while the epoxy is still wet. The next day peel the film and tape off, and if the indent is still there, do it again. When it is like glass, use a good grade automotive spray paint to match the existing color, but mask any other colors around so the fine mist spray won’t settle on it.

My carbon kevlar QCC and my wifes has had a dozen of these fixes, and you would never know it.

I have also done it many times on my kevlar boats that are clear coated.

Jack L

Jack L

Get one of those No No Pro things that
use mysterious heat rays to remove recurring hair growth.

Seriously, though, when I had to resurface two ww decked boat bottoms that had gotten very fuzzy, one with Nylon fuzz (Phoenix) and one with Kevlar, I made initial progress with a shaving razor, but the Kevlar was more resistant.

So I got a propane torch and waved it over the boat surface, slow enough to burn off the hairs, but fast enough not to overcook the resin.

The Nylon fuzz yielded easily, but Kevlar is used in fire resistant clothing. The Kevlar fibers sparked and burned back into little clumps. But those clumps could be caught and cut with the razor or a scraping knife.

Sounds like a Plan!
Thank you Jack & G2D

I was leery of torching as I didn’t want to create fuses but a little heat sounds promising. After I’ll do the squashed clear epoxy approach.

Thanks again.

See you on the water,


The River Connection, Inc.

Hyde Park, NY

Another thought
Apply resin to the affected area, once cured you can sand off the fuzz with wet/dry sand paper, then apply your gelcoat.

Good plan for a gouge because the fibers
remaining after clipping will help the resin hold in place.

Having that bit of clear coat on top is an advantage. The boats I deal with have no clear coat, only a very thin layer of pigmented or non pigmented resin. The problem I had with the boats described below was that Nylon or Kevlar was right-at-the-surface.

If I had been dealing with a gouge into Kevlar or Nylon, I would have dished out the damage a tiny bit, and then have put a layer or two of fiberglass over it. After hardening, the glass and resin will sand smooth, as you indicated.

Although S-glass is harder and stronger, it is overkill for most little gouges, and one should use, maybe, a flat weave glass. And glass mat compatible with epoxy is now available. Another problem with S-glass is the fibers are so fine that it doesn’t wet out clear. Not as pretty.

Sanding works well …
To get rid of almost all fuzz. A layer of epoxy as suggested will cement the area. If it needs to be sanded, sand as much as needed, and if some fuzz shows, here’s what you can do before gel coating. Change to a fresh high quality piece of sand paper and very gently (without pressure, pretty much) sand off the fuzz without taking more of the material off. This worked well on a carbon-Kevlar weave I worked on. It won’t get glossy as fiberglass, but there won’t be any standing fibers left either. Then gelcoat it or paint it.

Can you put gelcoat over epoxy? I’ve always heard that you can’t, so never tried.

A scraper works better than sandpaper
The carbide scrapers you can get at home centers and hardware stores work the best.

Yes, you can
The epoxy must be fully cured and any amine blush must be removed, but once that’s done, it will work fine.

I tried a furniture scraper with hook
edge, and it did work to an extent. Then I tried the torch…

Good advice inside & out
So to update, no I did not rediscover that rock. I darned well know where it is now.

Turns out that I did need to do some touch up where my heels contact the hull on the inside so coating with epoxy and then grinding off the now stiffened formerly fuzzed Kevlar ends worked just fine. I’ll recoat and apply a bit of 2oz. cloth just to create a bit more durable plate for my heels. Too much torso rotation? Can’t be!

To the outer hull, I had to go back an unfix a fix. I had started to use Spar Varnish which is what Impex used to recommend for their clear coats to cover up scratches. Works well on scuffs with a fine tip brush and a steady hand. Doesn’t work well to fill in an area. Takes forever and would require more coats than I’d have patience for.

Ground it down a bit and did the clear epoxy with a smooth plastic cover taped down and with some thick stacks of catalogs for weighting. Worked very well. Still need to feather the edges with some sand paper and finish with polishing compound so it’s perfectly clear again but I might just opt to go paddle.

That’s news.

See you on the water,


The River Connection, Inc.

Hyde Park, NY

Heel wear
It’s surprising how easy sandy heels go through Kevlar. I’d suggest putting down at least 6oz patch of glass under the heels if it’s already worn through a layer of 5oz Kevlar. I’ve done a bunch of them, if there’s a quarter sized hole under each heel I’ll make two little patches for the wear spots then put another rectangular piece of glass over that.

It’s the resin that’s giving way.
And one factor may be that (opinion based on a source I came across) Kevlar’s bond to vinylester and polyester is a little bit weaker than that of most other boat cloths. (If Salty comes by, he may second this.) So the Kevlar fibers can get pulled loose from the resin, and then Kevlar’s extreme toughness means the fibers may tend to pull the resin apart.

If the inner layer were polyester, with a vinylester resin, the bond is much better, and the polyester fibers defend the resin better It’s accepted that polyester and vinylester make a reasonably tough but fairly smooth-wearing surface.

Heel spots and other wear surfaces are sort of the exception that proves the rule that Kevlar “belongs” as an inside cloth.

You may want to consider…
…applying Dynel heel patches, as it’s very abrasion resistant.