Products for bench top machinists | LittleMachineShop.com

Insert, TCMT-21.51 Carbide

Insert, TCMT-21.51 Carbide - Main image
$5.07 $6.95 In stock

TCMT-21.51 carbide insert is a 60° triangle with a 7° relief. The center hole is a 40°-60° single countersink, and there is a single-sided chip breaker.

It has an inscribed circle (IC) of 0.25" (1/4"), a thickness of 0.094" (3/32"), and a corner (nose) radius of 0.0156" (1/64").

The insert is designated TCMT21.51 (ANSI) or TCMT110204 (ISO). 

Inserts are sold individually—no need to buy a pack of 10 inserts.

*NOTE: Make sure you get the correct inserts and retaining screws for your indexable turning tools. Our chart of indexable inserts shows which inserts and which screw to use with each of our indexable tools.

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Customer Reviews (4.6 / 5 · 5 reviews)

Joshua T. ★★★★★

Took a chance on this TCMT-21.51 insert for a light finishing pass, and the 7° relief angle really helps with the chip flow. The single countersink hole seated perfectly on my bar, no wobble at all.

Aurora ★★★★★

That single-sided chip breaker really clears the chips away on my aluminum parts, no more stopping to clear the cut. The 1/4" inscribed circle fits my tool holder perfectly.

George ★★★★★

I was a little worried about the 1/4" IC being too small for my holder, but it fits perfectly and the chip breaker cleared chips nicely on some 304 stainless.