I am building a new MIG cart for my 211.
The lower frame is .065 wall 1 x 2 and the front axle is solid rectangular.
I made some brackets from 3/16 to bolt the axle to the frame.

I'm wondering if I should employ crush tubes in the design, to keep from crushing the tubing where the axle bracket attaches through the tubing frame?

I'll most likely use 5/16 bolts.