Out of CCMT cobra carbide ferrous inserts + observation about toolholders for those inserts

I was using the Colchester lathe on Tuesday and I believe I installed the last ferrous cobra carbide CCMT inserts. Unless there is a secret stash somewhere, I couldn’t find another box in the cabinet directly in front of the bridgeport.

I also noticed that our tool holders for this sort of insert were labeled to be for a CCGA insert, which is a slightly different geometry than CCMT in that its relief angles are more acute and its screw hole position is offset away from the insert tip about 20 thousandths. The holders certainly still hold the CCMT insert and it works, but I wanted to mention it in case it wasn’t known.

A cursory search of google reveals that CCGA inserts are only made with diamond and CBN cutting edges, so this might be a moot point for us, as I doubt we’ll want to replace our toolholders for this slight geometry mismatch. But perhaps in the future, if they need to get replaced, we could get CCMT holders instead.

@Team_Machine_Shop

Good day! We have some new inserts and tool holders coming!

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