Very good point Gavin. Jim Marske covers this in some detail at the URL below;
http://www.continuo.com/marske/carbon/carbon.htm The carbon will stretch, hope this is the correct way to view the problem, much more than the wood (modulus of elasticity?), so you must use more carbon than you might expect when mixing it with wood in a spar. In a conference I attended a few years ago Joe Alvarez of Polliwagon fame mentioned that you could replace a wooden spar completely with carbon rod from Marske at a 1/20 ratio. That is compute the area cross section of the wooden spar and then use 1/20 of the area as the amount of carbon to build the carbon spar. Denny ... "One tst is worth 10,000 expert opinions." Irv Culver GavinandLouise <gdono...@bigpond.net.au> wrote: Be careful!!!!!! if you don't put enough Carbon to take all the load in it's own right, you run the risk of it breaking, and then transferring the load to the timber that it is laminated with. and if you've scrimped on the timber it'll break as well CRASH!!!!!!!! Use either one or the other. And which ever you use USE enough of it to carry the load. Gavin Australia ----- Original Message ----- From: "Alexander Birca (MD/RMD)" To: "'KRnet'" Sent: Tuesday, July 13, 2004 7:50 PM Subject: RE: KR> Carbon Fibre spars > Hi Duncan, > could you please post Ed Blocher's site URL, I couldn't find it... > > Alex Birca, > Moldova > > > > Hi, > I visited Ed Blocher's site, and saw some photos of his laminated spar. I > noted with interest his inclusion of a couple of layers of carbon fibre in > the laminations. And this got me thinking... > > Is this a good/bad/neutral thing to do? > > What would be the pros/cons of a completely CF spar? > > Duncan of Devonport > Auckland, New Zealand > > _______________________________________ > to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net > please see other KRnet info at http://www.krnet.org/info.html > --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.718 / Virus Database: 474 - Release Date: 09/07/2004 _______________________________________ to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html --------------------------------- Do you Yahoo!? Yahoo! Mail is new and improved - Check it out!
