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Re: Best material for abrasion resistance

Posted: Thu Feb 25, 2010 1:51 pm
by gstanfield
Shine, have you ever used the kevlar/aramid hybrid weave? One of the composite suppliers has some and it looks kinda neat, but I have no idea what it would be best for. Other than the cool look it provides that is :)

George

Re: Best material for abrasion resistance

Posted: Thu Feb 25, 2010 2:30 pm
by tech_support
gstanfield wrote: Other than the cool look it provides that is :)

George
for most applications, thats the main reason for using it. :)

I have not had an application where that type of cloth makes sense, at least when it comes to cost/benefit.

Re: Best material for abrasion resistance

Posted: Thu Feb 25, 2010 5:11 pm
by gstanfield
I kinda figured that was the primary use for it. I've made some motorcycle parts from CF and it was primarily for looks seeing as how saving about .5oz isn't gonna make the bike any faster than say skipping breakfast would have :)

Thanks,
George

Re: Best material for abrasion resistance

Posted: Tue Mar 02, 2010 8:31 am
by Tex 2009
It seems kevlar is heavy. How much weight would kevlar add to a hull of 20' length?

Re: Best material for abrasion resistance

Posted: Tue Mar 02, 2010 9:46 am
by tech_support
not much. It might take a little more epoxy to wet out equally weighted kevlar vs. glass, only because its difficult to know when you have added enough with kevlar, so you end up using more than needed to be safe. As an estimate, let say you might use 1.2 times the weight of the kevlar cloth in epoxy to wet it out. So if you using 5 oz kelvar, then it would take 11 oz of weight in cloth and resin per square yard of covereage

Re: Best material for abrasion resistance

Posted: Fri Jun 25, 2010 9:47 pm
by lncc63
Hi Guys. I've a few quick questions:

1) Would having Kevlar improve the resale value?
2) Would vacuum bagging eliminate all the difficulties of applying a layer of Kevlar?

Re: Best material for abrasion resistance

Posted: Fri Jun 25, 2010 10:10 pm
by gstanfield
Hmm, I would say #1 depends on how good of a salesman you are. People who don't know any better could easily be sold on the idea that a kevlar boat is the best in the world, etc

As to #2, I don't know

Re: Best material for abrasion resistance

Posted: Fri Jun 25, 2010 10:22 pm
by PAR
Kevlar is a good choice if you have more money then you know what to do with, but more importantly if you have quite controlled laminating conditions. Without climate control and surface controls you're just kidding yourself.

Abrasion resistance would be greatly improved with Xynole or Dynel fabrics, instead of 'glass. Xynole is a polyester fabric and by my testing, is about 6 times better at abrasion resistance then regular 'glass of similar weight. Dynel is a modified acrylic and also very tough, though according to my tests only about half as effective as Xynole at abrasion. The last time I checked Xynole it was pushing $9 a yard, while Dynel was about $10.

Both of these fabric drape especially well and one reason they are well liked. You'll see Dynel covered decks as a fairly common upgrade in the industry, because it wears so well.

As in every aspect of yacht design, there are also trade offs. Both of these fabrics drink resin. About 2 - 3 times the usual amount of resin then regular 'glass of similar weight. Also these fabrics do not offer any additional stiffness or strength, just water proofing and abrasion resistance. Application of these fabric requires some skill as they will float if you're not careful and they can be difficult to remove small bubbles on, as the fabric doesn't get transparent on wetout. They're not as difficult to apply or finish as other fabrics.

Re: Best material for abrasion resistance

Posted: Sat Jun 26, 2010 9:22 am
by rick berrey
What about S 2 glass, would it be a compromise between E glass and kevlar. rick

Re: Best material for abrasion resistance

Posted: Sat Jun 26, 2010 11:12 am
by PAR
S 2 'glass is a little stiffer and a little stronger then regular 'glass, but about the same in abrasion resistance, plus it costs the same as Xynole.