Main Menu

• About

• Recently Written

  • Steadicam Prototype v3 Test
  • 3A style topstage
  • Changes changes
  • Design + Development = wow, I respect engineers even more now.
  • Prototypes are frustrating
  • Shock mount for boom pole
  • DIY HMI pt 3
  • DIY HMI continues
  • FEA follys
  • Canon 5DMkII makes me want to accept 30P

• Categories

  • Lighting Equipment
  • Machining
  • Steadicam
  • Uncategorized
  • Video Equipment
    • Cameras

• Search

• Archives

  • April 2009
  • March 2009
  • February 2009
  • November 2008
  • July 2008
  • June 2008

• Links

  • Cinevate
  • Hackaday
  • Home Built Stabilizers
  • nNovia
  • Tom11 Films

FEA follys

Turns out the FEA I’ve been doing with Solidworks 2007 was based on some mis-information.  I was using Cosmos Express (the simple/beginner’s FEA tool in SW2007) and once I realized that I needed some sort of saftey factor on my parts, suddenly I couldn’t make anything strong enough to hold the 300lbs that the spring would be pulling inside each arm segment.  I decided to look at some different materials than 6061-T6, and that’s when I found that SW’s material library had the yield strength of 6061 @ 8000psi.  Wikipedia and ALCOA list it as a yeild strength of “over 35,000PSI” (http://en.wikipedia.org/wiki/6061_aluminum)  which is quite a big difference!  Now that I made that change in SW, suddenly all my parts are more than strong enough.  

I also re-designed my spring holding apparatus- I’m running 5 steel springs of a smaller diameter to get enough range of motion, and hold enough weight.  The upside is that I can also run 4 if I find that it’s way too strong for my camera, or I can run just 1 for very light weights.

Comments