CAT, BT Holders For Large Heads

Direct Mount Tool Holders For Large Boring Heads

Direct Mount Holders – CAT50 & BT50

Part No. Description
BT 550.160 BT50 Tool Holder - 160mm reach
CT 550.160 CAT50 Tool Holder - 100mm reach

Large Head Adapter Mount

Part No. Description
ADT 100-50 Large head adapter - adds 50mm length

Tool Holders For Adapter Mount Option

Part No. Description
BT 340.100.200 BT40 Tool Holder - 200mm reach
BT 350.100.170 BT50 Tool Holder - 170mm reach
BT 350.100.260 BT50 Tool Holder - 260mm reach
BT 350.100.320 BT50 Tool Holder - 320mm reach
CT 350.100.190 CAT50 Tool Holder - 190mm reach
CT 350.100.260 CAT50 Tool Holder - 260mm reach
CT 350.100.320 CAT50 Tool Holder - 320mm reach
HSK 100A.100.185 HSK100A Tool Holder - 185mm reach

Use With 300, 400, 500 Series Heads

Part No. Description
A 300, A 400, A 500 Finish heads - 300, 400, 500
D 300, D 400, D 500 Rough heads - 300, 400, 500


  • Maximum rigidity and accuracy
  • CAT, BT, HSK100A spindles
  • Nickel-chrome alloy steel ensures best reliability and repeatablility

Large Boring Head Mounting Instructions

installation large boring heads diagram

Refer to diagrams above for finish heads and rough heads.

1. Loosen slide block screws (#19 finish heads, #16 rough heads)

2. Remove set clamp screws (#20 finish heads, #17 rough heads)

3. On finish boring heads only, remove shield lock screws #4

4. Move slide blocks / shield off-center until the four counterbored bolt holes located in the body below the slide blocks are completely exposed.

5. Place taper shank holder or adapter on back side of boring head with pilot completely engaged in pilot cavity.

6. Insert 4 socket head cap screws into counterbored holes and tighten to 90 ft-lbs torque.

7. Push slide blocks back into position to line up with threaded holes below.

8. Insert nut / close shield lock screws and tighten

9. Adjust boring head to desired diameter and tighten slide block lock screws