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All Products ➞ Bordo ➞ Drills ➞ Specialist ➞ Stub Drills ➞ Black Metric HSS Bulk
11.5mm HSS Black Stub Drill
| Part Number: | 2021-11.50 |
| Brand: | Bordo |
| Barcode: | 9326518037743 |
| Pack Qty: | 5 |
| Feed per revolution mm: | 0.23 |
| Spindle Speed Aluminium/Brass RPM: | 1689 |
| Spindle Speed Cast Iron RPM: | 665 |
| Spindle Speed Free Cutting Steel RPM: | 1191 |
| Spindle Speed Malleable Iron RPM: | 748 |
| Spindle Speed Med. Carbon Steel RPM: | 831 |
| Spindle Speed Stainless Steel RPM: | 332 |
| Spindle Speed Tool Steel RPM: | 499 |
| Spindle Speed Wood/Plastic RPM: | 2520 |
| Diameter (mm): | 11.5 |
| Flute Length (mm): | 47 |
| Overall Length (mm): | 95 |
About this item:
- 11.5mm HSS Black Stub Drill
- Stub drills (screw machine twist drills) have a shorter overall length than Twist drills for maximum rigidity and longer tool life.
- 135° Split Point (crankshaft point).
- Split point is self centering and the short distance from the drill axis to the outer corners results in faster penetration, reducing the need for end thrust.
- They are designed primarily for machining operations in lathes (screw machines) but can also be used in manual hand held drills.
- Bordo Stub Drills have two helical flutes with 30 degrees of helix angle. This provides fast chip ejection and very stable drilling operation.
- Black Finish Stub Drills (also called blue finish) achieve their distinctive colour by steam tempering, a thermal process resulting in a porous tool coating.
- Black finish tools are generally recommended for ferrous applications where the oxide layer aids chip flow and heat dissipation.