Hex shafts?

[Karibou]

Originally Posted by Chris is me

Be sure you get steel or 7075 aluminum, rather than 6061.

I have to second that. We used hex shafts in our 6WD in 2008 (which was the first year we made the switch from keyed shafts after what I believe was a sheared keyway in 2007, same drivetrain), initially made of steel. We brought aluminum replacements to our first competition to try and save a little on weight. I don't know what kind of aluminum we used - Mark, you might know - but we ended up with an axle that had to be sheared off and pounded out of the wheel (if I remember correctly, it got bent during a match).

Every bot is different, but make sure that you know exactly what kind of performance you need from your shafts, including any mishaps that may happen in a match setting. The drivetrain is the one assembly that you can't afford to have knocked out.