I bought a special mandrel to use in tuning the plastic tires for a pine car derby (kid in cub scouts) and it was the right size. My cordless reachargeable dremel didn't have the power to do the job, but my old corded one works like a champ. If I worked on a lot of balls, I would get the real bevel tool though.
I think the mandrel cost less than 5 bucks at Michael or ben Franklin.
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