Quote Originally Posted by mklotz View Post
Yes, nicely machined. However, someone needs to tell him that one never taps T-nuts all the way through. If you do and then by accident tighten a bolt through to the point where it bottoms out in the slot and begins to lift the nut against the lips of the slot, you can break the lips out of the table.

A recovery is possible. If he damages the threads near the bottom of the nut so a bolt won't thread through he'll be safe. I'm not sure what the best tool to do that is. First thought is a cold chisel but what do I know?
I was taught (from a YouTube video) that you do tap through, and then deform the exit threads to prevent the screw bottoming out and breaking out the t-slot. Method suggested was putting the T-nut in a vise or arbor press with a steel ball bearing slightly larger than the root of the threads, and clamping down on it to get the deformation desired. I cannot swear that is the best way to do it, but seems pretty good to me. Wish I could tell you whose video it was, but that was over a dozen years ago, IIRC. I didn't start subscribing or bookmarking videos until a while after that.

Bill