Structural Framing Strength?

[R.C.]

Originally Posted by JB987

VexPro has a fantastic supply of structural components that are easy to build with and easier on your wallet...1x2" and 1x1" tubing with pre-drilled holes on 1" centers, a big collection of reasonably priced brackets with holes on 1" centers. Incredibly easy to cut and assemble with rivets or screws. Sure wish we had these supplies available for our rookie year in 2002

What Joe Said,

http://www.vexrobotics.com/vexpro/we...ersaframe.html

http://www.buildblitz.com/

And you can check out the robots made from the versaframing etc...

[DonRotolo]

40x40 is overkill for almost every application in FRC.

That being said, the material is plenty strong, its weakness are where it connects together. Fasteners that depend on friction (such as T-nuts) absolutely will come loose and move. Maybe OK for superstructure, but not for a drive base.

You will be far better served by getting several pieces of extruded box tubing in 1" x 1" with 1/16" and 1/8" wall, plus some 3/4 with 1/16" wall for smaller mechanisms. You will also need some sheet aluminum, start with 4x4 sheets on 1/32", 1/16", 1/8" and maybe 0.093". (It would be very rare to need anything thicker)

Try onlinemetals.com, but beware: They will give you an "extra 5% off" coupon after your first order...so place a small order first, then go for broke. They also run sales on occasion, like 25% off, or free shipping, ror something - so place that first order then see what comes up...

[asid61]

Originally Posted by DonRotolo

Try onlinemetals.com, but beware: They will give you an "extra 5% off" coupon after your first order...so place a small order first, then go for broke. They also run sales on occasion, like 25% off, or free shipping, ror something - so place that first order then see what comes up...

I just missed a 25% off sale they were having for Black Friday. Sign up for their email list and pounce on the sales that come around once or twice a month.

[pfreivald]

We've used Bosch Rexroth for linear motion applications--their drive carriage is fantastic. 30x30 is overkill for most applications, though.

The kitbot drivetrain is sufficiently good that I certainly wouldn't use structural framing for it....

...and for upper mechanical work, with limited manufacturing capabilities I don't think you can go too far wrong using square tube stock, L-stock, and clinch nuts (aka rivnuts aka rivet nuts aka threaded inserts). A couple of bags of 10-32 clinch nuts, a thread setter (the tool used to install them), 10-32 socket head cap screws, and some 19/64 drill bits will go a long way toward cheap, do-it-yourself, easy-to-modify-and-install "structural framing" that is versatile for prototyping, and easy to lock in place with a little Loctite for use on a competition robot.

It takes a more effort than an off-the-shelf solution but is far cheaper and lightweight, it isn't as lightweight or as sophisticated as CnC sheet metal fabrication but requires virtually zero expertise and is more modular. It's a happy medium between the two that I wish I'd known about as a rookie.