[Paul Copioli]

The VEXpro 3/8" and 1/2" hex shafting was meant to do just that. They are designed as undersized shafting such that they fit into the hex bearings without the hand modifying.

The problem lies with the hex bearings themselves. We are working on this problem and we will reach out to AndyMark and WCP to standardize on the hex bearing size and tolerances since there is no standard for this in the bearing world today.

I am investigating the claim that the VEXpro 3' hex stock was oversized, because this is the first time I have received that complaint about the hex being oversized.

Our QC department has checked hundreds of the hex shaft and they all come within tolerance. We checked all of our hex gears on this shaft and they all "just work".

If there are cases where the shaft didn't work with one of our gears, sprockets, or hubs, please contact me and we can work it out with you. A lot of additional time, tooling, and development effort went in to making a custom hex shaft that holds the undersized hex tolerance so that it just worked without hand sanding and filing. As a side note, my team used tons fo the 1/2" shaft and we did not have to hand file any of the shafts to work with the VEXpro gears, hubs, and sprockets.

With regards to straightness, the 3/8" shaft definitely has some bow. partially, this is due to shipping methods, but mostly it is due to the process by which the shaft is made and the length to diameter ratio of the shaft.

It is possible to get much straighter shaft if the length is around 12" per part. If there is interest in the shorter length for a tighter straightness tolerance, then I will have my team investigate the possibilities.

Paul