A-arm material
A-arm material
(OP)
Does anyone know if there is a composite material or lightweight metal for wich you could design into an A-arm for a baja vehicle? I am using double A-arms on the front suspension and I would like to change the upper A-arm to a lighter, but very durable material. The lower A-arm is 4130 Chromoly steel.
Any suggestions what to use?
Thanks!!
Any suggestions what to use?
Thanks!!
My website: http://www.geocities.com/kare6





RE: A-arm material
You may be able to design a composite a-arm which can withstand the loads associated with it, but I would be concerned that it wouldn't provide sufficient stiffness for that application. A-arm stiffness is a very important parameter for the handling and performance.
Have you investigated using aluminum instead? That could provide a significant savings, and still give equivalent stiffness to the steel part.
Good luck,
Brad
RE: A-arm material
I like bradh's aluminum suggestion better.
RE: A-arm material
Weight wise there is very little in it. The carbon fibre was the lightest, but not by 10%. For high stress components I prefer chrome moly, but generally I prefer MIG welded 6061. On problem with that is the softening at the joints - an A arm should be heat treated (and then straightend) after welding.
With an upper arm you are primarily chasing stiffness, not strength. Therefore carbon fibre would not be expected to be a particularly good choice - its strength is its main virtue. To us the difference is that 4 people on our team can MIG weld well enough to trust (not me), whereas we had to hire Jim to build a carbon fibre structure that we could not repair easily, if it broke, which admittedly it hasn't yet.
Cheers
Greg Locock
RE: A-arm material
Adam
Team Chemical Interaction
Wentworth Institute of Technology Mini-Baja
RE: A-arm material
Stick with 4130 tube. By the time you fabricate, or have fabricated composite control arms, your weight savings will not offset your loss of points because of cost.
I also made some ctrl arms for my GT5 Datsun, and found a significant weight savings by pressing spherical bearings into the pickup point rather than rod ends. I pressed Al in the ends, crimp, drill, and press the bearing. Super light. Good luck!