It is currently August 20th, 2019, 5:48 pm

All times are UTC - 5 hours




Post new topic Reply to topic  [ 37 posts ]  Go to page 1, 2, 3  Next
Author Message
PostPosted: April 9th, 2019, 2:26 pm 
Offline

Joined: June 28th, 2001, 7:00 pm
Posts: 1651
Location: Freeland, Maryland USA
I know some of you are on the Canoe Tripping board, but thought this an interesting enough experiment to repost. Eight (ten) different skid plate material layups, impact tested, abrasion tested, bottom epoxy inspected and pliability tested.

http://www.canoetripping.net/forums/for ... ce-results

Long testing story short:

Kevlar felt sucks for impact resistance.

A single layer Dynel skid plate is better, lighter and woven-material impressive in both impact and abrasion resistance.

If you want additional impact resistance adding a layer of E-glass (or E-glass tape) underneath seems as good as anything.

I didn’t think to test anything and everything material-wise, and am convinced that the under-cloth, laid on the bias, would increase impact resistance.

Now if the manufacturers (I’m looking at you, and you and you) would just stop offering G-awful thick, heavy, ugly kevlar felt skid plates as an option. At least freaking pigment that fugly looking shit. Or, ya know, just don’t use kevlar felt as skid plates.

Pblanc is as good as I’ve seen at modern materials skid plate installation. He might be willing to come teach y’all how to properly install a neat, clean-edged Dynel or sandwiched material skid plate. Taking the demo-abused canoe home with him seems like a fair deal.

Yeah, it would take longer to install a proper skid plate, and require more attention to sequence and detail, but it would be better, lighter and more effective than %&*#@! fugly kevlar felt.

Seriously, it’s not the 1970’s anymore; kevlar felt skid-plates long ago had their day.


Top
 Profile  
 
PostPosted: April 9th, 2019, 7:51 pm 
Offline
User avatar

Joined: December 20th, 2003, 9:27 am
Posts: 929
Mike,
I really appreciate all of the testing that you do of various products. It helps with decision making. Thanks for doing these. Now to find Dynel in Edmonton!


Top
 Profile  
 
PostPosted: April 9th, 2019, 10:55 pm 
Offline

Joined: March 23rd, 2006, 11:21 pm
Posts: 1076
Location: Burns Lake, BC
Thanks Mike.

Very useful, as usual.


Top
 Profile  
 
PostPosted: April 10th, 2019, 10:44 am 
Online
User avatar

Joined: August 8th, 2017, 9:14 am
Posts: 823
I'm going to skid plate my other Royalex this summer - one of them already has factory kevlar plates. For my other canoes impact would not be a big factor but for the Royalex it is. Never heard of Dynel so now have to try to figure out what it is and go find it :-)


Top
 Profile  
 
PostPosted: April 10th, 2019, 8:58 pm 
Offline
User avatar

Joined: June 20th, 2001, 7:00 pm
Posts: 3449
Location: Toronto, Ontario Canada
I have been unable to find a Canadian supplier for Dynel.

Most of the US suppliers unfortunately want to ship via UPS or USPS Express or Priority, makes the yard you need for multiple skid plates rather expensive.

_________________
"What else could I do? I had no trade so I became a peddler" - Lazarus Greenberg 1915


Top
 Profile  
 
PostPosted: April 11th, 2019, 6:35 am 
Offline

Joined: June 28th, 2001, 7:00 pm
Posts: 1651
Location: Freeland, Maryland USA
recped wrote:
I have been unable to find a Canadian supplier for Dynel.


That’s odd. All of the US suppliers I order from (Sweet Composites, Jamestown Distributors, Express Composites) carry Dynel. I vaguely recall one US supplier carries it under a different name.

It’s used in sailboat applications, maybe a Chandler.


Top
 Profile  
 
PostPosted: April 11th, 2019, 2:40 pm 
Offline
User avatar

Joined: April 18th, 2018, 11:13 am
Posts: 46
Location: Toronto
recped wrote:
I have been unable to find a Canadian supplier for Dynel.

This was my experience as well when I was rebuilding the bow and stern skid plates on my royalex boat last year. The old felt plates simply popped off with a chisel and were extremely brittle. I simply ended up using a kevlar layer on the base, with four layers of S-glass on top. I ordered the S-glass from Composites Canada (https://compositescanada.com/) as they carry several different weights of it. I think I got their name from one of your older posts recped.


Your testing info is great Mike, thanks! My inner geek is cheering.... :clap:


As well, i'd like to say a huge thank you to yourself, Pblanc, and ezwater (and others I may have omitted...) as the collected information on fabric and epoxy work that you've all contributed here on MYCCR, as well as on other forums was very helpful and useful when I was redoing those skid plates last year! Keep it up! I'm feel that I'm pretty capable and handy, but having never done epoxy work I was a bit nervous - your information certainly demystified working with cloth and epoxy, so cheers! My plates aren't pretty, but they're rock solid! :thumbup:

I ended up using the System 3 epoxy, as it was cheaper, simple to mix, and allowed me to buy a smaller quantity (I didn't want to invest in the pumps, etc, of the West products, thought I know it is widely used and loved). Maybe of interest for future testing, but I seem to recall their material spec sheets showing that System 3 had more inherent flex/elasticity than the West 105, but obviously much less that G-flex. (I have a cold crack - or maybe a "I backed up too far into my garage crack" - on my boat that I'm going to fix with g-flex this weekend or next hopefully...)


Last edited by Corbeau on April 11th, 2019, 3:28 pm, edited 1 time in total.

Top
 Profile  
 
PostPosted: April 11th, 2019, 3:23 pm 
Offline

Joined: June 28th, 2001, 7:00 pm
Posts: 1651
Location: Freeland, Maryland USA
Mike McCrea wrote:
I vaguely recall one US supplier carries it under a different name.


Xynole polyester fabric. “Nearly identical to Dynel”


Top
 Profile  
 
PostPosted: April 11th, 2019, 6:50 pm 
Offline
User avatar

Joined: June 20th, 2001, 7:00 pm
Posts: 3449
Location: Toronto, Ontario Canada
Maybe I'll bring in a roll from the US and sell single yards....any takers?

I'm guessing the price for a single yard including shipping would be CA$15 - $20......

_________________
"What else could I do? I had no trade so I became a peddler" - Lazarus Greenberg 1915


Top
 Profile  
 
PostPosted: April 12th, 2019, 11:30 am 
Offline

Joined: June 28th, 2001, 7:00 pm
Posts: 1651
Location: Freeland, Maryland USA
Corbeau wrote:
I simply ended up using a kevlar layer on the base, with four layers of S-glass on top


I recall Ezwater’s multi-layer skid plates. I never tried it myself; once even a single layer Dynel skid plate proved tough enough in (non-whitewater) use it seemed like a lot of layering work. I didn’t think much about adding any additional layers until the skid plate testing fun began to take form.

A multi-layer (Dynel, ? material on the bias, ? material laid straight weave) would undoubtedly be the toughest of all. That might be incorporated in another, better, round of skid plate testing, along with single under layers on the bias.

I have hopes that West System’s EpoxyWorks journal will reproduce that skid plate test, with actual scientific measurements and not just my observations. The impact bomb drops were their idea from a previous test.

https://www.epoxyworks.com/index.php/ti ... nderoga%27

Interesting test and results, worth clicking on the tables at the bottom. Note that Epoxyworks has Dynel and Xynole listed separately; they are not actually the same.

Some of those materials are a mystery to me. What the hell is BTI XM 1508? At least it is biaxial. The next skid plate I install will incorporate E-glass tape and Dynel, both easy availability in the US.



Corbeau wrote:
System 3 had more inherent flex/elasticity than the West 105, but obviously much less that G-flex. (I have a cold crack - or maybe a "I backed up too far into my garage crack" - on my boat that I'm going to fix with g-flex this weekend or next hopefully...)


Gawd bless G/flex. The most extreme acid test of G/flex is the decorative ceramic lid to the wood stove humidifier pot. Dropped and broken into several pieces (now many) years ago and glued back together with G/flex. It sits steaming water atop the wood stove all winter long. Still going strong.

I like G/flex for a lot of boat applications, sometimes it is the only thing that will work. But I also like it for household stuff, especially when I only need a teenyweeny batch of epoxy.


Top
 Profile  
 
PostPosted: April 13th, 2019, 6:46 am 
Offline

Joined: June 28th, 2001, 7:00 pm
Posts: 1651
Location: Freeland, Maryland USA
recped wrote:
Maybe I'll bring in a roll from the US and sell single yards....any takers?

I'm guessing the price for a single yard including shipping would be CA$15 - $20......


As the grandson of a Prohibition-era Rouses Point Customs Agent I do not want to promote smuggling, but Dynel from Sweets is $10 UDS for small yardage and $7.50 a yard for a small roll. (vs $14 a yard at Jamestown Distributors).

https://sweetcomposites.com/Polyester.html

Got a friend with a mailing address just across the border?

Out of curiosity I Googled around, checked some Canadian sailboat chandler sites and even called Composites Canada to no avail. You could corner the market on Canadian Dynel.


Top
 Profile  
 
PostPosted: April 13th, 2019, 7:18 am 
Online
User avatar

Joined: August 8th, 2017, 9:14 am
Posts: 823
The Chandler here in Ottawa does not carry it on their website at least.

I'd be up for a piece of yours recped. Shipped to Ottawa area.


Top
 Profile  
 
PostPosted: April 15th, 2019, 12:36 pm 
Offline

Joined: June 28th, 2001, 7:00 pm
Posts: 1651
Location: Freeland, Maryland USA
BTW, the “small roll” pricing on Dynel from Sweet Composites is any amount you want over 20 yards.


Top
 Profile  
 
PostPosted: April 16th, 2019, 2:47 pm 
Offline

Joined: June 28th, 2001, 7:00 pm
Posts: 1651
Location: Freeland, Maryland USA
About a “short roll” of Dynel; it (can be) pricier to get rolled material shipped, depending on the amount, but rolled fabric, of any sort, is so much easier to work with when laid out on a big cutting table. It lies flat and can be more accurately measured and marked under a T-square, yard stick or tape.

Folded stuff comes with creases, which are best avoided when cutting needed materials. Folded and creased Peel Ply is the bane of my epoxy release-treated-abric existence; the folded crease will always show on (hand laid) peel ply, if not under tactile feel at least visibly. An opaque top coat of UV pain does hide it.

If only for accurate cutting purposes it helps to re-roll anything that arrives folded, and let it sit for a few days/week. That won’t completely eliminate the creases, but it helps.

About Dynel as a single layer skid plate material, and BYOD (Bring Your Own Dynel). If the long \_/ sides came seamed/glued/whatevered, and cut symmetrically, they would be easy to end trim to length, covering the proven scrape and scratch areas, and easier to tape out with crisply defined edges for the epoxy/peel ply.

If someone could figure out how to symmetrically seal/glue/sew a selvage edge on two foot long trapezoids of Dynel, hell, I’d buy a couple. Please ship my order of selvage edge Dynel skid plates wrapped around old toilet paper cylinders; I’ll pay the extra for no folds.

Out of curiosity I searched for what that inner cardboard cylinder was called in the TP industry. More than you ever needed to know about toilet paper

https://en.wikipedia.org/wiki/Toilet_paper

Where was I? We have one last RX solo that doesn’t yet have skid plates of any kind; a well equipped, spray covered Wenonah Wilderness. My younger son’s go-to canoe. Fits him like a glove. Fits me like I need to move the seat 4” aft and lose 50 lbs.

It needs skid plates, maybe a length 2” E-glass tape under Dynel, under peel ply compression. With graphite powder and black pigment.

Soon, but I need to finish up a half dozen other projects first.


Top
 Profile  
 
PostPosted: April 16th, 2019, 4:29 pm 
Offline
User avatar

Joined: June 20th, 2001, 7:00 pm
Posts: 3449
Location: Toronto, Ontario Canada
Yeah the folding is a real issue but here in Canada the price differential to ship a yard rolled vs a yard folded is HUGE.

As you probably saw in your scan of Canadian suppliers, S-glass, Kevlar, Release (peel-ply) and all forms of epoxy are readily available here, the Dynel is the only missing part.

I'm going to run the numbers and see if I can come up with a viable plan to get small quantities out to Canadians as a reasonable price. I have a US mail drop in Niagara Falls and a fairly cheap courier who can bring it the rest of the way.

Mike, you might be able to take a guess at this question; if I have 1 yard of dynel could it be folded to fit inside a 9" x 12" envelope and still be less than 2cm / 3/4in thick? I can mail that "cheap" within Canada (oversize letter) but if it's thicker than 3/4in then the rate increases dramatically (we do not have an equivalent of USPS First Class Package here).

_________________
"What else could I do? I had no trade so I became a peddler" - Lazarus Greenberg 1915


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 37 posts ]  Go to page 1, 2, 3  Next

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group