02-08-2015, 08:30 AM
Now that's strange. I've never seen a negative rake TNMG insert using a mechanical chipbreaker before. I really don't believe that holder should be using one of those inserts.
Loosen that top clamp and remove the insert. If there's no eccentric screw in the center to engage the hole in the insert, the carbide seat under it is screwed down with a countersunk hex socket screw and the walls of the pocket have clearance angles, that means the holder is for TPG43x size & style inserts. At least that's my best guess based upon the style of holder being similar to ones I have, but for slightly smaller and more common TPG32x inserts.
If the holder is as I suspect, the insert is held flat and parallel to the top and bottom of the holder body. If it were a holder for negative rake TNMG's, it would hold the insert tipped downward at -5º.
I believe the box of ten "inserts" are actually replacement seat/shims, and may or may not be for that holder. It's easy to compare once you have that insert out.
Loosen that top clamp and remove the insert. If there's no eccentric screw in the center to engage the hole in the insert, the carbide seat under it is screwed down with a countersunk hex socket screw and the walls of the pocket have clearance angles, that means the holder is for TPG43x size & style inserts. At least that's my best guess based upon the style of holder being similar to ones I have, but for slightly smaller and more common TPG32x inserts.
If the holder is as I suspect, the insert is held flat and parallel to the top and bottom of the holder body. If it were a holder for negative rake TNMG's, it would hold the insert tipped downward at -5º.
I believe the box of ten "inserts" are actually replacement seat/shims, and may or may not be for that holder. It's easy to compare once you have that insert out.