MCMNN 12-3B Indexable Turning Tool Holder, 3/4" Square Shank, 3/8" I.C. 80° Diamond Insert, Neutral

MCMNN 12-3B — toolholder, 3/4" square shank, 4.5" overall length. Made in the USA by RMC Tooling.

Indexable turning toolholder from RMC Tooling, machined in the United States. The shank is ground to a qualified reference surface, so the tool goes back into the turret at the same cutting-point location every time it is swapped — no re-touching off, no lost setup.

Built for production lathes and CNC turning centers. The insert pocket, seat and clamping hardware are all standard RMC service parts, listed below, so the holder stays in service for years instead of being scrapped when a clamp screw strips.

Specifications

• Model: MCMNN 12-3B
• Shank width (A): 3/4"
• Shank height (B): 3/4"
• Insert I.C.: 3/8"
• Shank qualification: qualified back and end, 4.5" long
• Holding method: clamp and locking pin
• Insert shape: 80° diamond
• Holder style: straight shank, 40° side cutting edge angle
• Holder rake: negative
• Hand: neutral
• Brand: RMC Tooling — made in the USA

Need a clamp, seat, lock pin or screw for this tool? Send us the model number and we will match it.

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Specifications decoded from the RMC toolholder identification system (RMC 2020 catalog, page 2).