I bought a Chinese gap-bed lathe some years ago. Recently, I made the mistake of removing the gap insert. The problem appears to be that they don't bother to make the mating surfaces of the gap and the insert flat, nor do they appear to do much in the way of keeping debris from between the surfaces. So, when you attempt to put the insert back, it is nearly impossible to get it back in the original position. It's not in the manual that came with my lathe, but on the Grizzley.com web site, for a similar lathe they sell, they actually say, don't remove the gap insert, you'll never get it back in place!
Has anyone found a way to correct this?
I've been mulling over the idea of milling two slots in the bottom side of the insert to epoxy in some 3/8" square stock. First, I would have to remove a small amount of cast iron from the bottom of the insert to prevent any interference. Also, I would have to flatten out the corresponding surfaces on the gap. I would clamp the insert to the carriage, and then clamp the carriage to the bed so that the insert ways would be in alignment with the lathe. This would allow the square stock to rest on the gap in the proper position while the epoxy cured. Of course, slow-cure epoxy would be required.
