good post, where can I get the spreadsheet? regards Eben -----Original Message----- From: Mike Garton [mailto:[EMAIL PROTECTED]] Sent: 08 October 1999 09:33 To: Martin Brungard; RCSE Subject: [RCSE] Re: Composite Material Design Stress Martin Brungard wrote: > I wondered what others were using for the allowable > tension and compression stresses for various > composite materials. > > Tension Compression > carbon 250,000psi 56,500psi > kevlar 43,000psi 20,000psi > S glass 128,000psi 57,000psi The numbers you quoted from Ollie are realistic. It is dangerous to use "standard" numbers given by a manufacturer or in a textbook for composites. Metals may have standard values but composites do not. There is just too mutch variation in the results. The compression numbers can vary by more than a factor of ten. These are usually the most important numbers too. The real aerospace engineers make a sample, instrument it, and take new data each time they change a composite layup. You can go real conservative to avoid testing but then the plane is heavy and/or weak. RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
