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PostPosted: April 16th, 2021, 7:58 pm 
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Hi all,

I recently purchased a new kevlar canoe and was planning on guarding it with a kevlar resin guard. While looking for the resin I can across an article that was against this practice. Naming drag, weight, noise, and looks as reasons not to do it.

I am looking for opinions and experiences both for and against to make an informed decision.

Thanks,

Mark


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PostPosted: April 16th, 2021, 9:32 pm 
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Location: Geraldton, Ontario Can
I would say don't do it till you need to do it, and don't use one of those ugly felt kits. If you treat your canoe badly and need to do it, slap a layer of s-glass over the stems with some epoxy.


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PostPosted: April 17th, 2021, 8:16 am 
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Location: Freeland, Maryland USA
RHaslam wrote:
I would say don't do it till you need to do it, and don't use one of those ugly felt kits. If you treat your canoe badly and need to do it, slap a layer of s-glass over the stems with some epoxy.


Absolutely agree don’t use ugly (and expensive) kevlar felt kits, and mostly agreed don’t do it until some wear and tear shows where needed. I have installed a skid plate on a new canoe, but I wasn’t going to be home again for at least a year.

“Badly” is a subjective term, I’d prefer “long and hard”. We are rough on our canoes, and every boat we own has skid plates; some of those boats are from the 70’s and still going strong.

If you use S-glass I’d recommend putting down two layers of glass, one cut with the weave ### and one cut on the bias XXX, that will add some strength and a bit of additional durability.

For abrasion resistance a skid plate made from Dynel fabric is superior to S-glass, or any other fabric. Dynel fabric does not seem to be available in Canada. I’ve installed Dynel skid plates on a couple dozen canoes, as well as “experimental” skid plates using ghastly kevlar felt, E-glass, S-glass, thick bias woven Twaron, Dynel and etc, and Dynel has proven to have far superior abrasion resistance.

https://myccr.com/phpbbforum/viewtopic.php?f=49&t=47778

I’ve done a bunch of experimental abrasion and impact testing with Dynel vs other materials is search of hard data.

https://www.canoetripping.net/forums/fo ... ce-results

But this guy’s test was as revealing as anything I did. Quote:
A 6 pound fire brick held on a 45 degree angle
The test with 6oz fiberglass cloth took 52 strokes to cut through to the wood
The 5.5oz Dynel has more than 250 strokes and is still not through to the wood.

Unfortunately Dynel seems unavailable anywhere in Canada excepting via one kindly fellow who imported a supply to resell at cost.


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PostPosted: April 18th, 2021, 11:03 am 
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Joined: March 23rd, 2006, 11:21 pm
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Location: Burns Lake, BC
Not.

It would be built on the boat if it was necessary.
It's an option.

Like most options, people are swayed to think that they will need it before they even know what they need.
Don't get sucked into a solution for a non-existent problem.

I don't use them.


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PostPosted: April 18th, 2021, 12:52 pm 
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Location: Pickering, Ontario
This also interests me. I want to repair our older canoe, a 16' fibreglass Scott Tripper. The aluminum bow skid plate has popped a few rivets, and I've tried reriveting but haven't got ones long enough to get right into the fibreglass and grip. I was thinking of taking it right off and applying something new, like maybe fibreglass or kevlar. Is it possible to get something that would fit?

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“Believe me my young friend, there is nothing - absolutely nothing - half so much worth doing as simply messing about in boats. Simply messing.” - Ratty, The wind in the Wllows


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PostPosted: April 18th, 2021, 1:02 pm 
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Location: Freeland, Maryland USA
Canoeheadted wrote:
It would be built on the boat if it was necessary.
It's an option.
Don't get sucked into a solution for a non-existent problem.


If it is a new kevlar canoe from a reputable manufacturer it is likely to have something built into the boat; partials of different fabrics laid on the bias bow and stern for impact resistance, sacrificial gel coat for scrapes and scratches, specially formulated Vinylester or epoxy resin, etc.

As above, I’d wait X number of years, until some stem abrasion shows how long and wide an area may need to be further protected, and then install a single layer of Dynel fabric and pigmented epoxy resin, compressed under release treated peel ply, with the fabric cut an inch wider and a couple inches longer towards midships than that area.

Different canoe shapes, different loads and different paddler practices and abuse result in different abrasion areas, and stern skid plate coverage is usually different from the bow. I can kinda guess what area skid plates need to cover.

Sharp stemmed vee bottomed hulls may need a long skinny strip, blunt stemmed down-river or WW canoes a shorter, more bulbous shape. I’d rather the wear area be visibly demonstrated as time scrapes by.

A single layer Dynel skid plate with peel ply compression is all of 1/16” thick, and is tough as nails. (Caveat caution, uncompressed Dynel swells like an old sweatshirt and is wood rasp rough textured. Release treated peel ply, every time)

This is a 1974 (yes, now 47 year old) Klepper Kamerad. There are large, paint color matched Dynel skid plates on both bow and stern.

ImageP4170001 by Mike McCrea, on Flickr

ImageP4170002 by Mike McCrea, on Flickr

Gotta get mighty close to even tell those Dynel skid plates are there. Incredibly abrasion resistant, invisible, no-gurgle flush. Damn near seamless, and a couple of ounces each.

That vintage glass Klepper is a rare boat.

ImageP4170008 by Mike McCrea, on Flickr

Rarer still converted to a solo decked sailing canoe and open water tripper; it fits a 60L barrel behind the sliding Wenonah bucket seat, and sails like a champ with that massive rudder.

ImageP4170016 by Mike McCrea, on Flickr

Up for sale soon, shame the border is still closed.


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PostPosted: April 18th, 2021, 1:41 pm 
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Dave Bailey wrote:
This also interests me. I want to repair our older canoe, a 16' fibreglass Scott Tripper. The aluminum bow skid plate has popped a few rivets, and I've tried reriveting but haven't got ones long enough to get right into the fibreglass and grip. I was thinking of taking it right off and applying something new, like maybe fibreglass or kevlar. Is it possible to get something that would fit?


When I redid my older canoe I embedded some hardware cloth and maybe a layer of cloth over than. Then I applied filler and painted it so you could not tell I had a 'skid plate'

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PostPosted: April 18th, 2021, 4:01 pm 
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I agree that you should wait and see if you need them. Personally I hate them for all the reasons you mention.


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PostPosted: April 19th, 2021, 8:36 am 
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Location: Freeland, Maryland USA
Schmitty wrote:
While looking for the resin I can across an article that was against this practice. Naming drag, weight, noise, and looks as reasons not to do it.


Cliff Jacobson’s take on why kevlar felt skid plates suck?
“If you want to reduce the value of your canoe by about 200 dollars, put a thick, ugly skid plate on each end! Here’s why you don’t want skid plates!”

I couldn’t agree more with reasons to avoid using kevlar felt. Cliff’s advice in that article is to use woven kevlar fabric cut on the bias instead of thick ugly felt. It’ll work, but Dynel is more abrasion resistant than kevlar, and Dynel doesn’t fray as badly, even when cut on the bias.

I agree with all of the above negatives in the case of kevlar felt skid plates. A single layer of abrasion resistant Dynel is a different story.

Drag. None, compressed under release treated peel ply Dynel skid plates rest nearly flush with the stems.

Weight. 2oz +/- at each end.

Noise. None, see “nearly flush with the stems”.

Looks. If the epoxy is pigmented to match the hull, or the skid plates color match painted they are not unattractive. Dynel with un-pigmented epoxy turns out a milky white, not transparent like S-glass, so pigmenting the resin or top coating with paint is more aesthetically pleasing.

On most boats I use a little dab of black pigment and a half-ish teaspoon of graphite powder; that produces the blackest of black skid plates, with the color fully saturated through the fabric. The graphite powder adds an additional touch of toughness and a lot of slipperiness.

Some of these are new, some are repairs to old kevlar felt or S-glass skid plates.

ImagePB180013 by Mike McCrea, on Flickr

I’ll have a couple hard used white bottomed sea kayaks in the shop later this month, and plan to try a new epoxy additive, hexagonal boron nitride, aka white graphite powder.

http://www.microlubrol.com/MicroLubrol- ... icron.aspx

It’s another material experiment, but I enjoy shop experiments.


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PostPosted: April 19th, 2021, 1:56 pm 
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Location: Manitoba
Mike McCrea, your knowledge and your Dynel skid plates are impressive.

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Brian
http://www.JohnstonPursuits.ca

 


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PostPosted: April 20th, 2021, 7:14 am 
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Location: Freeland, Maryland USA
Paddle Power wrote:
Mike McCrea, your knowledge and your Dynel skid plates are impressive.


Thanks for the kind words. I have friends whose skills and techniques, and shop tools, far exceed mine. I think of it as “There’s a right way, a wrong way, and my way”. Any shade tree boat tinkerer with a few rudimentary tools could do it “my way”.

I am slowly getting better. I’ve been dinking around repairing and outfitting canoes and kayaks for 30+ years. I’m still learning, and enjoy sharing what I’ve learned, some of which has been by doing and trying, and some by pseudo-scientific experiments.

The Dynel and other skid plate material experiments went on for months, testing impact and abrasion resistance, flexibility, inspecting epoxy saturation by slicing the sample in half and, finally, just for the hell of it, shooting the sample skid plates and Royalex test panels with everything from .22 dust shot to .177 pellets to 22 shorts to a .410. I am now the world’s leading forensic examiner for bullet holes in Royalex ;-)

Someone mentioned that they thought my attachment method for securing a back band would quickly fail. That had yet to happened, but the comment got my curiosity up, and led to a weight bearing experiment, testing a variety of outfitting attachments and methods.

Here’s the synopsis of the results:

https://www.canoetripping.net/forums/fo ... post107909

The full expertiment, including hefting a cumulative total of a half ton of weights. Long and photo heavy:

https://www.canoetripping.net/forums/fo ... experiment

I do enjoy shop experiments, even the years-of-waiting for results stuff. The 55 month oil, varnish and epoxy test taught me a lot, and confirmed some suspicions about oils, varnishes and epoxy coatings.

https://myccr.com/phpbbforum/viewtopic.php?f=49&t=40923

Two long-term experiments are currently awaiting results. Painted test panels staged outside for eventual UV and weathering deterioration.

ImageP7210055 by Mike McCrea, on Flickr

Now hanging outside beside those test panels, five different cord lock, with induced spring corrosion.

https://www.canoetripping.net/forums/fo ... xperiments

I frequently paddle tidal waters, and use cord locks for some outfitting applications. Rust never sleeps, but I’d like to know the nap time.


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