Thanks for these comments and suggestions. I'd been thinking more along the lines of nippers or angle grinders, but no real experience needing to do something like this in some quantity. I was hoping a machinist might have a quick way of doing these easily with the right tool. I realize the quantity I'm asking for isn't real exciting, but if the product catches on could be a lot more.
Yes, I have made several prototypes, and they work well. They'll be used for securing an adjustable angle fence on table saw cross cut sleds, so not much clamping force is required. The fence can be removed and replaced at an alternative location, and I use magnets to "park" a set of nuts in a "home" position, and their large surface area allows for using larger more powerful magnets that hold just right. They ride on a baltic birch plywood face. The sides that face the clamp surface of these weld nuts (thanks for the correction), are pretty flat and smooth with some shallow radial striations. I'm a woodworker, and do own an edge sander that I think I could fixture as sfriedberg suggests, though it runs faster than it probably should for steel. What type abrasive and grit should I use for a belt for this job?
