BT40 Retention Knobs w/ Coolant Thru for CNC Tool Holders ISO 7388-2 Type A (often designated as LDA40)
These pull studs have a through-hole for through-tool coolant. Based on the international standard ISO 7388/2-1984 Type A, an LDA40 pull stud typically conforms to the following physical metrics:
- Machine Interface / Taper Size: BT 40 / SK 40
- Thread Size (g1): M16x2
- Knob/Head Diameter (D1): 19 mm
- Neck/Neck Bolt Diameter (D2): 14 mm
- Pilot/Shoulder Diameter (D3): 17 mm
- Coolant ID Diameter (D4): 7.5 mm
- Overall Length (L1): 54 mm
- Functional Length (L2): 26 mm
- Thread Length (L3): 20 mm
- Wrench/Drive Size (SW): 19 mm
