China Suppliers Factory HSK-A-FMB BT-FMA BT-FMB Face Mill Holders for Precision Machining

HSK-A-FMB holders use the HSK (Hollow Shank Taper) interface, which provides superior rigidity, higher clamping force, and better repeatability — ideal for high-speed machining centers. BT-FMB holders use the BT (MAS-BT) taper shank interface, which is widely compatible with conventional and CNC milling machines. The choice depends on your machine spindle type and application requirements.

FMA holders are designed for face mills with inch-standard bore sizes (e.g., 25.4mm, 31.75mm, 38.10mm, 50.80mm), commonly used with American-standard cutters. FMB holders are designed for metric bore sizes (e.g., 22mm, 27mm, 32mm, 40mm), suitable for metric-standard face milling cutters. Selecting the correct type ensures proper fit and secure clamping of your milling cutter.

The BT-FMB-BG series features an extended taper shank (BG) design, which provides additional support and rigidity for deep-reach or extended-length milling operations. This design helps reduce vibration and deflection when machining in deep cavities or when a longer projection length is required, making it suitable for applications where standard-length holders cannot reach the workpiece.

The "C" suffix (e.g., FMB22C, FMB27C) indicates that the holder includes a coolant through-hole (water hole) feature, allowing coolant to be delivered directly to the cutting zone for improved chip evacuation and tool life. The "F" suffix (e.g., FMB40F, FMB60F) typically refers to a flange-type design with a different mounting configuration, as indicated by the Figure "B" type in the specification table. Always verify the water hole column (√ or -) in the specification table for coolant capability.

To select the correct face mill holder, consider the following key parameters: (1) Spindle interface type — HSK-A, BT30/40/50, or SK30/40/50; (2) Cutter bore diameter (D1) — must match your face mill's bore size; (3) Total gauge length (L) — choose based on the required projection from the spindle face; (4) Coolant requirement — select a "C" suffix model if through-coolant is needed; (5) Washer requirement — check the washer column to ensure compatibility with your cutter's retention screw. Refer to the specification tables above for complete dimensional data.

No, SK-FMB holders are not directly interchangeable with BT holders. SK (Steilkegel) holders use the DIN 69871 / ISO 7388 taper standard, which is common in European CNC machining centers, while BT holders use the Japanese MAS-BT standard. Although both are 7:24 taper types, their pull-stud (retention knob) interfaces and flange dimensions differ. Always confirm your machine spindle specification before ordering to ensure correct holder compatibility.