pic: FRC558's modified VEXpro Drive in a Day

[JesseK]

Originally Posted by TD78

Anyone have thoughts on using 3/8" steel rod as dead axles? Tap both ends of the axle and it'd be close to using tube axle/bolt. I wouldn't think a 1/4"-20 bolt would work...not enough thickness left in the rod. Something smaller like a #10 or #8...at which point you would have to drill all 4 holes in the DIAD sideplate, rather than using the pre-punched 1/4" hole for the outer wheels (of the 8wd)...but it could work.

We had great success with 1/4" steel rod that was put through a die on either end with locknuts in 2007. 2011-2012 we moved to 3/8" steel rod that was supported similarly. It was quite easy to machine - stick the die into a vice, stick the rod in a cordless 18V drill, use lots of tap magic and BAM 30 seconds later you have an axle. Just make sure the mount hole hits the solid rod and not the threads.

As for maintaining proper wheel alignment & spacing - I'd recommend any solid non-deforming material for standoffs. The dark-grey plastic from Andymark works great (it's why it's in the KOP, or was last time I used a KOP).

I agree that the axle itself should NOT be used to stiffen a frame. The only load you want on a wheel axle is normal to the floor so it rides correctly on the balls inside the bearing.