[Austin2046]

If you're going with the kitbot chassis and/or don't have a lathe than it may not be as important... but we use a lot of 1/2 inch hex shaft, 1/2 inch round flange bearings and 1/2 inch hex bearings... we use the shaft for our drive axles, collectors, shooters... anything that turns. Our first year we used round or keyed shafts, we did not know the wonders of hex shaft.