Phillip Harrison wrote:

I' planning on a veil did you use one?

No, if you mean did I use a Kevlar veil.  That one thread was more Kevlar 
than I needed or wanted on the plane.

What you may be missing is that the real structure of a KR wing is the wood 
spar underneath the skin.  The skin's not going to fail unless you strike it 
with something, and if they are carbon fiber you'll break out a chunk and 
either continue your crash or keep on going (if it was a Canadian goose). 
The only reason I used carbon fiber on my wings was because I could make the 
wing a little lighter, yet much stronger (to minimize hangar rash and 
survive the inevitable runway light collision), and I could afford the extra 
cost (back when CF was "cheap").

You asked for advice, and I guess that's mine.  You are welcome to use 
Kevlar and extol it's virtues after you're done.

This reminds me of a conversation I had with the chief engineer this 
afternoon.  He wanted some advice on cutting  cost out of a 10" diameter 
carbon fiber tube for a piece of space hardware that we were asked to quote 
to build.  Unidirectional prepreg CF tape .0002" thick was specified by the 
customer, which cost $700/lb, with a 25 pound minimum order. Wall thickness 
was called out as .040" to .090", so it was going to take something like 200 
layers of this stuff wound around the tube to get to minimum thickness.  It 
took me about 2 seconds to bust out laughing...why would anybody specify the 
most expensive and laborious way to build this piece if the weight of the 
tube had a tolerance of more than double the minimum weight and thickness?

Mark Langford
ML at N56ML.com
website at http://www.N56ML.com
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