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In the past I've always done the body binding radius by hand but it's a tedious process. These pics show an attachment for a small pneumatic die grinder to allow using a corner rounding bit (1/16" R.) with 0.500" pilot bearing. I made the sleeve from 1.5" diameter aluminum stock by step drilling/boring the ID to clear the bit, collet nut and then a snug fit on the grinder body. I did do a light cleanup pass on the OD of the grinder body to make sure it was concentric with the spindle as the first step.
The end of the "nose cone" serves as the depth limiting means and the end of the grinder body bottoms out inside the attachment Seems to work well at least on ABS binding but haven't tried it on wood.
Had originally planned on some type of fine adjustment for depth but found that snugging the collet, installing the device and then tapping the bit to desired depth works good. The sleeve can then be slipped off for tightening the collet.
Nelson