Bamboo Tips - Tips Area
Rod Design - Stress and Strain

< Home < Tips Area < Rod Design < Stress and Strain


I got curious about Garrison's math, so I got a couple of books and read up on the subject of stress and strain. First, I replicated Garrison's formula for stress - not to see if he was correct, but to see if I was interpreting the stuff in the book correctly.  I then pulled some general equations from the book and worked them so that they'll accurately predict the the stress for a Penta and a Quad (perfectly square one).  After discussing this a bit via email with Bob N., I added some equations and information for a "rounded" Quad.  Then Adam V. mentioned hollow-built, so I added some more equations that predict the stress for hollow Quads, Pentas, and Hexs.

I had previously put together a single spreadsheet in MS Excel that is the equivalent of HEXROD, but not as user-friendly.  It will, however, enable one to come up with a rod taper for a Quad or Penta that will exactly match the stress curve for a Hex rod.  The Quad can be either a perfect square or a "rounded" square - the spreadsheet does both.  Also, any of the rods can be hollow-built.

I've sent both the PDF file and the spreadsheet to several of the list members to look at.  I'd be happy to email the spreadsheet to anyone who asks for it.  (Claude Freaner)


Site Design by: Talsma Web Creations

Tips Home - What's New - Tips - Articles - Tutorials - Contraptions - Contributors - Search Site - Contact Us - Taper Archives
Christmas Missives - Chat Room - Photo Galleries - Line Conversions - The Journey - Extreme Rodmaking - Rodmaker's Pictures - Donate - Store