I bought a set of 5 tool bits from Harbor Freight- some call them Horrible Fright. My tool bits all use triangular inserts and are held in place with a screw that fits into a countersunk, through, hole in the center of the insert. HF does not offer inserts alone, as best I can determine. I have some TNMM-332 inserts which are close enough sized to work, but the hole diameter in the TNMM inserts is a bit too small for the screw and the TNMM is not countersunk. As far as I know, I have no way to drill the carbide hole larger. The HF inserts have no ID at all on them. Where can I find inserts for my bits?