Deep Hole Drilling Guidelines

 
Step 1: Approach
  • 50 RPM max
  • 12 IPM (300 mm/min)
Details:
  • Feed the longer drill within 1/16" (1.5mm) short of the workpiece at a maximum of 50 RPM and 12 IPM (300 mm/min) feed rate.
Coolant: OFF
Step 2: Feed-In
  • Speed at 75% of recommended start
  • Feed at 50% of recommended start
Details:
  • Drill 3/4" deep at 75% recommended speed and 50% recommended feed to establish the hole.
Coolant: ON
Step 3: Deep Hole Drilling - Blind
  • 100% RPM
  • 100% IPR (mm/rev)
Details:
  • Drill to full depth at recommended speed and feed for longer drills (according to Allied Machine speed and feed charts).
  • No peck cycle recommended.
Coolant: ON
Step 4: Deep Hole Drilling at Breakout
  • 50% RPM
  • 100% IPM (mm/rev)
Details:
For through holes only:
  • Reduce speed by 50% prior to breakout.
  • Do not break out more than 1/8" (3mm) past the full diameter of the drill.
Coolant: ON
Step 5: Drill Retract
  • 50 RPM max
Details:
  • Reduce speed to a maximum of 50 RPM before retracting from the hole.
Coolant: OFF
Tool failure can cause serious injury. To Prevent:
  - When using holders without support bushing, use a short T-A® holder to establish an initial hole that is a minimum of 2 diameters deep.
              - Do not rotate tool holders more than 50 RPM unless it is engaged with the workpiece or fixture.
Visit www.alliedmachine.com/Support/Safety/Deep-Hole-Drilling-Guidlines/T-A®-and-GEN2-T-A®.aspx for the most up to date information and procedures. Factory technical assistance is available for your applications through our Application Engineering Team.