SNMG 120404 / SNMG 431, chip breaker BF, grade FM324 — negative square turning insert.
1/2" inscribed circle, 3/16" thick, 1/64" corner radius. The BF breaker is the finishing geometry: 0.002–0.010 ipr (0.05–0.25 mm/rev) at 0.02–0.06" (0.5–1.5 mm) depth of cut. FM324 is a PVD grade — universal multi-purpose grade for mid and low cutting speeds — low-carbon and alloyed steel, stainless, cast iron, Inconel and titanium alloys.
42 RMC toolholders in stock take this insert — square, 0° — negative clearance, 1/2" inscribed circle, 3/16" thick. Pick by the shank your turret takes.
| 5/8" shank | MSDNN 10-4B |
| 3/4" shank | MSDNN 12-4B · MSDNN 12-4C · MSKNL 12-4B · MSKNR 12-4B · MSRNL 12-4B · MSRNL 12-4C · MSRNR 12-4B · MSSNL 12-4B · MSSNR 12-4B · SBL 12-4 · SBR 12-4 |
| 1" shank | MSDNN 16-4D · MSKNL 16-4D · MSKNR 16-4D · MSRNL 16-4D · MSRNR 16-4D · MSSNL 16-4D · MSSNR 16-4D · SBL 16-4 · SBR 16-4 |
| 1-1/4" shank | MSDNN 20-4D · MSDNN 20-4E · MSKNL 20-4D · MSKNL 20-4E · MSKNR 20-4D · MSKNR 20-4E · MSRNL 20-4D · MSRNR 20-4D · MSSNL 20-4D · MSSNL 20-4E · MSSNR 20-4D · MSSNR 20-4E |
| 1-1/2" shank | MSDNN 24-4D · MSDNN 24-4E |
| 1" x 1-1/4" shank | MSDNN 85-4D · MSKNL 85-4D · MSKNR 85-4D · MSRNL 85-4D · MSRNR 85-4D · MSSNL 85-4D · MSSNR 85-4D |
Boring bars and interchangeable heads. 16 more RMC tools take the same insert for internal turning. See RMC boring bars →
TURNING KNOW-HOW
Practical guides to choosing, understanding and using your inserts.
Explore the grade and chip-breaker selection chart for your turning operation.
Explore the chart 02 / INSERT CODESUnderstand turning-insert designations and what the letters and numbers mean.
Read the guide 03 / CUTTING PARAMETERSLearn how to use a turning formula calculator to work through the numbers.
Explore the formulasFM Carbide maintains stock in the USA. If this item is not in stock, estimated time to ship is 14–21 calendar days.
Estimated time to ship is measured in calendar days, from order placement until your order is handed to the carrier. Carrier transit time is additional. Orders may ship sooner. We accept orders awaiting replenishment; please contact us before ordering if you need a specific shipping date.
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