Kayak bottom protection

Builder's Forum
1

I've dreamead of building a CLC kayak for some time.  I can see it being used as recerational and fishing kayak on local lakes.  So I'm thinking the Wood Duck family of kayak.  I also see wanting to take it to a local river that I ocassionally rent a canoe and float down river.  Often times there are shallows and the canoe scrapes hard on a gravel beds for a few feet.  How would a CLC kayak bottom fair in this environment?  Should I not even consider this type of environment?  What does one do to protect the bottom from scrapes?

 

 

2

   If you build a beautiful wooden boat with a bright finish, you will inevitably experience some heartache when it first begins to pick up scratches. And it will get scratched. After a while, you'll recognize that you would rather have a working boat than a museum piece, and the scratches will quite bothering you so much.

Having said that, much still depends on the kinds of scratches you put in the hull. If the river bed is covered with rounded rocks and pebbles, the scratches will be insignificant. But if you are dragging over broken oyster shells and clamshells and razor-sharp chert or limestone, you can slice right through the varnish and the fiberglass. Once you nick into the wood, you have a problem that needs fairly immediate repair. Such repairs are easy . . . but you'll have trouble getting back to the museum piece.

3

Everything Birch2 says is true. For my WD12 I used a graphite/epoxy coating on the bottom. That keeps most scratches from penetrating the glass and is easily repaired.

  

More details at the link. Have fun,

Laszlo

4

   Thanks for the comments.  I like the working boat concept.  That will help keep me in check as to how fancy I would get with the build.  I wondered if people added different coatings or even some UHMW skid surface materal.  This river is in Michigan, so smooth round rocks.  The river guides that use their drift boats almost daily say they get the bottoms recoated annually.

6

   My kayaks are finished bright - of course paint would be easier for touch up.  I'm not experiencing much abrasion here in TX as I try to avoid the water where I know I'll scrape (I've got a plastic one for banging in rapids), but even so I've used these tough protective strips on the keel.  At a minimum, it lets me set the boat down on some rocks or a concrete ramp or parking lot, even if I know I won't be dragging it around, at least knowing that I don't have to worry about a lot of scratching as I load gear in the boat, etc.. 

"PereGuard Kayak Keel Guard 2" Width BLACK" is available on Amazon and I'm sure many other places.  I think you have width choices up to 4".  I stuck with 2".  You might consider 2" width fore and aft where the joinery angle is more acute, and 4" near the middle of the boat where the angle is more obtuse.

I started doing a Google search on different options to discuss, but quit because there are enough that you'll want to do your own picking and choosing.  Other options include brand names Keel Guard, KeelEasy and Gator Guard.  There is a place in Wyandotte, MI on e-Bay selling 2" width KeelEazy for $4 a foot, and you get to choose the length.  Looks like a good option.  KeelEasy and Pereguard seem to be the same stuff. 

If you go this route, add enough to wrap some or all of the rise of the stem and stern upturns.  Follow instructions, use a heat gun and give a nice hard strecth/pull around bow/stern curves to avoid wrinkles.

I've also tried some of that "as seen on TV" Flex Tape.  It works, too, but has a softer surface, is harder to apply without wrinkles and probably not as good as things mentioned earlier.

You could do chines as well as the keel, or at least chines near the middle of the boat where it is wider, if desired.  Even with chines and keel done, you would still have exposed bottom areas, but not the areas that take the high-pressure scraping.

This option does add a little weight - maybe no more than Laszlo's bottom coating, though.

In all cases, once applied this stuff is pretty well stuck and I think will require a mild heat gun to remove.

Just a very quickly and easily installed, and realatively easily removed, option you might consider.  I think the appearance of the boat remains fine with this stuff installed, and it isn't visible (except bow and stern) when right side up on the water, so there's that reason to stay that way!

7

You need to read this.................

   https://www.clcboats.com/life-of-boats-blog/what-happens-when-stitch-and-glue-boats-age.html

be sure to view both parts one and two. Provides good pictures and comments.

8

You built the bottom. You finished the bottom. You can refinish the bottom. .

Yes, I scratch the bottom of my varnished Ch 17. Yes, it has had some oyster shell damage that cut fabric, but only once in three and a half years. That boat goes out a lot. Its been capsized against I-75 bridge column covered with barnicales. Its been grounded on many concrete boat ramps. Its been drug on the rocks of lake Superior. It has been drug on rocks on the UP. It has been scraped by a dock bolt on the St Johns river in Florida surfing through the pilings. It has been high centered on logs in the swamps of Florida and Georgia. It has rubbed on a loose roof rack. Yes I've refinished it many times. But the real truth is that the epoxy is real tough. It rarely takes a serious damage.    Most of the damage is a scrape from something in the varnish. A little sanding and revarnishing and its ready to go again.

.

I still say that the first thing you do when the boat is first finished is take it out to the drive way and drop it on the concrete. Get the grief over early and start enjoying your boat.

9

Every time I take my Shearwater sectional out it comes back looking like the boat in the blog Grumpy linked: https://www.clcboats.com/life-of-boats-blog/what-happens-when-stitch-and-glue-boats-age.html

The blog's author says that's just normal wear and tear, and can be fixed with just a "light sanding and fresh varnish" as long as the fibreglass isn't penetrated.

Cosmetically, however, it's not very appealing to the eye.  

Is there any alternative that would better protect the bottom of my boat from scratches?   Would Laszlo's graphite/epoxy mix work?  What about coving the bottom with carbon fiber fabric?

Thanks

 

10

That is a well-used boat.

Carbon fiber is very stiff for very little weight. It's also relatively brittle and not particularly durable on its own. That's why where it would have to stand up to abuse it's typically covered with glass fiber. I wouldn't use it, that boat needs protection more than stiffness.

You could try kevlar, instead. It's much more durable. It's also expensive and a pain to work with. Dynel fabric is less expensive and heavier, but also troublesome for hand layups. I wouldn't use those, either. Glass is cheaper and easier to work with.

If you're worried about weight, then just go with the graphite/epoxy after you've fixed the penetrations to wood. It's easy to repair and won't look as bad as the scratched varnish. It's also the least work to apply.

You could also add another layer of 4 oz glass to the whole bottom, add 4 oz strips along the seams and put graphite/epoxy on the entire area below the waterline. That would weigh more, but be well-armored.

Alternatively, skip the glass strips on the seams and cover them with Keeleazy after the graphite/epoxy. A bit more weight and trouble, but pretty much nothing will get through to the seams then.

Have fun,

Laszlo

 

 

11

All stony/rocky beaches around here in SW Turkey (the picture is typical)so on all of my boats I put thicker fibreglass on the bottom than called for in the plans. The little extra weight is of no consequence. Like Laszlo, the bottom of my C17LT is coated with graphite and that has helped but after having to do a bit of repair on the bow I never run straight into the beach nowadays but come in parallel. I have a strip of Kealeazy on there now.

 

I haven't put graphite on the bottom of my WD14 as that is usually used with the sail rig and it's a lot easier to jump out a couple of metres from the shore but it still has heavier fibreglass on the bottom.

12

Laszlo & Tambo, do you put epoxy OVER the kealeazy strip?

Do you use the graphite powder from West Systems that CLC sells?  When you scratch it, how do you repair it?  Cover it with a small patch of graphite/epoxy?

Thx

13

Keeleazy on fully-cured epoxy, nothing on the keeleazy.

Any graphite powder meant for use as an epoxy additive is fine. I bought mine from CLC.

Quickest fix is to wipe it clean with denatured alcohol, then paint on some new graphite/epoxy mix. If you want to impress the fish looking at your boat's bottom, you can do some sanding before and after applying the graphite/epoxy mix to make it perfectly smooth, but that's very messy and you'll never get the colors to match exactly.

Have fun,

Laszlo

 

14

As Laszlo said for repairs and kealeazy. I live in SW Turkey and got my graphite powder from a Turkish company via the internet. 

It's horrible to work with and some tests were necessary to get the mix right but Laszlo had done a whole lot of tests so I only had to do a couple as I was almost certainly using different exopy (again, locally sourced). I'm not sure where we'd all be without Laszlo!

15

   Thanks so much for your help.   :-)