CCMT vs CCGT Inserts

CCMT and CCGT are both 80° rhombic positive turning inserts and often carry the same size code (a CCMT 09T304 and a CCGT 09T304 are the same physical size), which leads buyers to assume they're interchangeable. They're not — the difference is in how the cutting edge itself is made and what it's built for.

Same shape, different manufacturing

CCMT inserts are pressed/sintered with a moulded edge, generally suited to finishing steel, stainless steel and general-purpose non-ferrous work. CCGT inserts are precision-ground after sintering, giving a sharper, more polished cutting edge with tighter dimensional tolerance — the fourth letter in the code (M vs G) reflects this difference in manufacturing and tolerance class.

Why CCGT suits aluminium

Aluminium and other soft, gummy non-ferrous materials tend to stick to a dull or rough cutting edge, causing built-up edge and a poor surface finish. The sharper, polished edge on a CCGT insert resists this far better than a standard moulded CCMT edge, which is why CCGT (and related ground inserts like DCGT, TCGT, VCGT) are the default choice for aluminium turning and finishing.

Can you use one in place of the other?

CCMT can be used on aluminium for less demanding work, but expect more built-up edge and a rougher finish than a ground insert would give. CCGT is not intended for ferrous materials like steel or cast iron — its sharper, less robust edge wears quickly under those cutting forces.

Choosing between them

If you're machining steel, stainless steel or cast iron, CCMT (or a similar general-purpose positive insert) is the right starting point. If you're machining aluminium or another non-ferrous, abrasive-free material and finish quality matters, CCGT is built for that job. Tell us your material and operation and we'll confirm which is right for you.