BT30 Toolholder Info

Looking for information about assembly, care and maintenance of BT30 toolholders for documenting my makerspace 1100MX. So far have found the following resources.

BT30 Toolholder Assembly

Tormach Info
NOTICE! You must only use BT30-45° (ISO7388-3-JF30-45) type pull studs with this machine (Pull Stud, BT30-45°(PN 37553)). Other pull stud types or angles can cause damage to the pull stud clamping mechanism.

Use the following items to tighten the pull studs to 40 Nm (30 ft lb) of torque:
-Socket, BT30 Pull Stud (PN 39420)
-Tool Tightening Fixture, BT30 (PN 39681)
-Torque wrench Under- or over-tightening the pull studs can cause poor contact between the tool holder and the spindle taper.

Tool Holder Setup and Machine Loading Procedure

Techniks Torque Specifications
ER 20 - COLLETS I.D. OVER 1/16″ (2MM) - 59 ft/lbs
ER 20 - COLLETS I.D. UNDER 1/16″ (2MM) - 24 ft/lbs

Machinist’s Guide to Toolholder Maintenance


Notes from Hoffman, P. J., & Hopewell, E. S. (2019). Precision Machining Technology. Cengage Learning.

National Machine Tool Builder (NMTB) series taper: 30, 35, 40, 45, 50 and 60. Taper of 3 -½” per foot.

Common flange types: CAT flange (V flange) and BT flange. CAT pull studs (retention knobs) have inch-series threads, BT pull studs have metric threads.

Collet styles: ER, TG and DA. ER-type collet size range is ~1mm (~0.040”)

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