A static holder clamps a turning tool or boring bar rigidly in the turret. Nothing rotates in the holder; the workpiece does the cutting motion. These are the stations doing your turning, boring, facing and grooving.
A driven (live) holder takes rotary drive from the turret, so a drill, tap or end mill turns while the main spindle is stopped or indexed. That is what lets a lathe do milling and cross-drilling in one setup. Mongtec publishes 228 driven tool holder article numbers alongside these static holders.
Almost every turret runs both. The usual mistake is buying driven holders for every station when half the work is plain turning — static holders are cheaper, stiffer and there is no drive train to wear out.
| Interface | Static holders | Types | Driven article numbers |
|---|---|---|---|
| BMT40 | 2 | ID, OD | — |
| BMT45 | 10 | Face, ID, OD | 7 |
| BMT55 | 16 | Double OD, Face, ID, OD | 19 |
| BMT65 | 12 | Double OD, Face, ID, OD | 11 |
| BMT75 | 9 | Face, ID, OD | 6 |
Carry two square-shank tools in one turret station. On a turret that is already full, this is how you get another tool into the cycle without giving up a station.
Available in BMT55 (1), BMT65 (1).
Present the tool to the face of the part rather than the diameter — for facing, grooving and back-turning operations.
Available in BMT45 (4), BMT55 (5), BMT65 (2), BMT75 (4).
Hold a round boring bar for internal turning and boring. The bore size and the reach you need decide the model.
Available in BMT40 (1), BMT45 (3), BMT55 (6), BMT65 (6), BMT75 (3).
Hold a square-shank turning tool on the outside diameter — the workhorse station for roughing and finishing the OD.
Available in BMT40 (1), BMT45 (3), BMT55 (4), BMT65 (3), BMT75 (2).
The catalogue lists compatible machine brands per holder. These are the brands that appear:
It clamps a turning tool or boring bar rigidly in the lathe turret. Nothing rotates inside the holder — the workpiece turns and the tool stays fixed. That is the opposite of a driven (live) holder, where the turret drives a spindle inside the holder so a drill or end mill can cut on a stationary workpiece.
A typical turret runs OD holders for outside turning, ID holders for boring, and face holders for facing and grooving. Double-OD holders put two tools in one station, which is how you add a tool to a turret that is already full. Tell us the operations and the machine and we will work out the mix.
No. BMT (Base Mount Turret) is an industry de-facto standard; it is not published by ISO or DIN. Two turrets both labelled BMT55 can differ in bolt circle, key position and clamping detail between machine builders. VDI, by contrast, is standardised in DIN 69880. This is why Mongtec verifies against the actual turret drawing before quoting rather than selling against a label.
No. Mongtec supplies the full dimensioned drawing by email once an enquiry is open, so it matches your actual machine and turret configuration.
Driven tool holders by interface · All driven article numbers · PSC / ISO 26623 · Machine model index · Selection guide
Angle heads for machining centres · tooling for 81 lathe builders (133 published models) — BT30, BT40, BT50, HSK-A63, HSK-A100 right-angle machining heads.