Howdy, I'm thinking about replacing the front bolt-on axle of my 29er wheelset with a QR axle. I measured the current solid axle with a pair of calipers and found the axle diameter to be 9.5mm or 3/8". Bearings are 1/4", despite being a front hub (Is this normal with mountain hubs? I know the common size for for ROAD hubs is 3/16"). I guess it goes without saying the hub is a cup and cone style.

Ideally, I would like to be able to convert the solid axle to a 9mm QR as it would allow the wheel to be used with most modern sus forks. My question is if it is possible to convert the axle diameter from to 9.5mm to 9mm for a hub that takes 1/4" balls?