Screw Extractors

1/4in (6.35mm) Left Hand Drill Bit Carded - Cobalt Series

Product Code: 9LI14COL

Key Features
For the removal of damaged bolts (stud) and screws
Ideal for Stainless Steel and Hi-Tensile Steel
Fully ground HSS Cobalt increases strength and drill life
Improves heat resistance for increased strength and drill life
135 Deg Split Point cuts faster and reduces wandering

Technical Specifications
Brand ALPHA
Series Cobalt
Type of Measure Imperial
Diameter (in) 1/4
Flute Length (mm) 34
OAL (mm) 64
Barcode 9342386099041
Category Screw Extractors
Longest side (mm) 200.00
Median side (mm) 40.00
Shortest side (mm) 7.00
Weight (gr) 30.00
Box Quantity 10.00
Carton Quantity 140.00
Order Quantity 1
Unit Of Measure
Box: 10
Carton: 140
  • For the removal of damaged bolts (stud) and screws 
  • 8% cobalt 

 

Technical data:

  • Diametre: 1/4″, 6.35mm 
  • Overall length: 64mm
  • Flute length: 34mm 

 

Directions for use: 

  1. If possible, grind or flatten the head of the damaged bolt or screw.

  2. Use a heavy hammer and centre punch to mark the centre of the bolt or screw. This will prevent the drill from wandering.

  3. Drill into the bolt or screw in reverse using a small size left-hand drill with a variable speed reversible drill.

  4. If the bolt does not reverse out, use the small hole as a pilot hole and change to a larger size left-hand drill. Most bolts come out before the hole drilling operation is finished.

  5. The drill will grab the bolt when breaking through the backside. Typically, this is the stage when the broken fastener will spin out of the threaded hole. When drilling through the broken bolt, vibration will help to break the bolt free.

Note: If this drilling operation has not removed the broken stud or bolt, the hole drilled will form a pilot hole for a screw extractor.


Relevant page in the Alpha catalogue
Products to compare:
Comparing Products