SINER 12-3 — boring bar. Made in the USA by RMC Tooling.
Internal Boring Bar for Threading & Grooving Inserts.
Steel-shank indexable boring bar from RMC Tooling, machined in the United States. Ground shank, standard indexable geometry, and a rigid clamping system sized to the bar diameter — the combination that keeps chatter down at the depths where boring bars usually give up.
Sized by minimum bore, so start there: pick the largest bar diameter your bore will clear. Every clamp, lock pin, seat and screw in this bar is a stocked RMC service part, listed below.
These are the service parts RMC lists for this exact model — not a generic cross-reference. Every one is stocked.
| Insert | NG-3L |
| Clamp | CM-73 |
| Clamp screw | S-412 |
See all RMC spare parts & hardware →
Not sure how to read an insert code? Turning insert designation explained.
Dimensions as published in the RMC 2020 catalog, page 52.
