BT and BBT tool holders

This is the widest family Mongtec builds — twenty-five holder types on the BT and BBT tapers, from an ER16 collet chuck through to an ATC arm alignment tool. All of it is cut to JIS B 6339 with a taper tolerance tighter than AT3.

Material and quality specification

Taper standardJIS B 6339
MaterialAlloyed case hardened steel
Surface treatmentBlackening or bright
Taper toleranceTighter than AT3
HardnessHRC 56–60
Case depth0.8 ± 0.2 mm
Surface roughnessRa below 0.2 µm
Balance gradeG6.3/15000 and G2.5/25000
CoolantForm AD; AD/B on request

Mongtec publishes these numbers because they are the ones that decide whether a holder holds its accuracy after a year in a real shop. Ask for them from any supplier you compare against.

Taper sizes

BT30 / BT40 / BT50 · BBT30 / BBT40 / BBT50

Collet chucks

ER collet chucks →

ER collet chuck, UM nutER16 to ER50, DIN 6499, clamping 1 to 34 mm
ER collet chuck, hex nutER16 and ER20
ER collet chuck, mini nutER11 to ER25, reduced nose diameter
ER collet chuck, shortCompact build
ER collet chuck, GER nutER16 to ER32
Power milling chuckø20 to ø42, clamping 3 to 42 mm
OZ collet chuckDIN 6391, OZ16 to OZ32
TG collet chuckTG75 and TG100
High speed SKS collet chuckSKS10 to SKS25
Pull back collet chuckClamping 1 to 12 mm
Precision screw collet chuckClamping 4 to 32 mm

Face and shell mill holders

Face mill and shell mill holders →

Face mill holder, inch3/4″ to 1-1/2″ — for shops running inch arbors
Face mill holder, metricDIN 6357, ø16 to ø60
Combi shell mill holderø16 to ø40

End mill holders

End mill holders →

End mill holder, Weldonø6 to ø50, coolant version available (K)
End mill holder, whistle notchø6 to ø40
Screw-in milling cutter holderM8, M10, M12, M16 threads

Adapters, drilling and tapping

Morse taper adapterMT1 to MT5, tang or drawbar, DIN 6364
Tool holder adapter sleeveBT to BT, and BT to HSK-C from HSK32C to HSK100C
Drill chuck adapterB12, B16, B18, B22
Keyless drill chuck holderClamping 1 to 16 mm
Precision drill chuck holderClamping 1 to 16 mm
Quick change tapping chuckWith length compensation, M3 to M33

Adjustment, modular and metrology

Runout adjustable flange adapterø60 to ø140
Flange adapter sleeveModule to HSK-C
UM adjustable tool holderø12 to ø32
Boring bar blankMachine your own
Test arborø32, ø40, ø50 × 300 mm
ATC arm alignment toolFor setting the tool changer arm

Dual contact (BBT)

Stability at speedThe flange face and the taper both carry load, so the holder stays put at high rpm
Surface finishLess deflection at the nose shows up directly in the finish
Dimensional accuracyRepeatable position means repeatable size
ATC repeatabilityThe holder returns to the same place every change
Boring roundnessBetter roundness on bored features
Tool lifeLess vibration, longer edge life

Dual contact only works if the spindle is cut for it. Mongtec builds dual contact holders to the industry-standard geometry — confirm your spindle is a dual contact spindle before ordering.

Body diameters (D, D1), gauge lengths (L2, L1) and the set-screw thread (G) are in the printed catalogue and are supplied with the quotation.

Send the operation and the spindle taper — we quote the right family

CNC mill tool holders → · Shrink fit tool holders → · Hydraulic tool holders →