ding resistance? carbon vs. kevlar vs. fiberglass?

General Discussion
21

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Even with breather cloth and the peelply the dynel sucked and retained too much resin.  The board came out too heavy for all the money and work put into the board. 

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I was thinking about running strips along the rails over balsa or HD foam figuring it might be worth a shot for ding resistance.

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I'd go with S cloth or some of that new 6 oz. biax instead of the dynel, unless your going to bag.  I couldn't find the syntex which sounded better so I went with the dynel.  Also like it says the dynel doesn't wet out transparent and it is very very resin hungry.   I went over my notes and found that I used perforated film over the wet out dynel in the bag.  I should have went with peelply and a poly breather to improve the cloth to resin ratio instead.

In the end though I came to the conclusion that making a bomb proof board can sometimes be just a bomb instead of a board.

22

Dynel can be used similarly to Kevlar, not quite as strong,

alot more stretchy.  Dynel, like kelvar is lighter than resin,

therefore it floats, giving the appearance of being

“Resin Hungry”(thirsty?) 

The boat guys do it like so: lay on a thin coat of resin, using a roller.

roll out the dynel, tighten with a squeege, let it “A” stage,

then another thin coat over usually squeegee’d on to fill the weave.

 

Polyolefin is similar to dynel; stretchy & thermoplastic.

Hope this helps.

Pete

 

PS

If bagging, like DMP says, peel ply and poly bleeder.

On that note(hints from a cheap bas***d):

                    peel ply =nylon dress lining from fabric store

                    breather = high loft quilt lining(batting).

Pete

 

 

23

Carbon fiber is very strong at resisting tension. But, it is not very impact resistant. Aramids are much more impact resistant. But, they are very tough to work with.

Back when Clark first closed their doors, I had a project board made. It was a 1/2 pound eps blank. I had my glasser use Corecell and Impact glass with Resin Research in an effort to avoid the extra steps of laminating balsa skins. The corecell is an impact glass with microballoon bonded to it. It did an incredible job at impact resistance. But, it did a terrible job of keeping the board light and simplifying the build process. 

Then Greg Loeher and Ken Ebert started distributing dual density blanks. I forget the exact foam densities. But, the rails were around three pounds and the center was around a pound with your choice of parabolic stringer materials. I think that is the direction you are headed.