Broken Tap Removal Tools – Tech Help/How To

Armor Mills and Armor Mills: Broken Tap Removal Tools Help and FAQ

Broken Tap Removal Tools

Armor Mill™ and Armor Drill Tools are Premim Solid Carbide Broken Tap Removal Tools used to drill out broken high spreed steel and cobalt steel drills and taps.

These extremely rugged tools can drill into rough and jagged shaped broken drills or taps where other tools might walk, unless spot drilled with a larger drill.

Due to both tools rugged design, they can also be used to machine hardened Steels, Granite, Armor Plate and other very hard materials.

  • Armor Mills and Armor Mills are designed for use in a rigid tool holder, in CNC Machines, Machining Centers, Kneemills, and Lathes with the parts held securely.
  • Produced from a Premium, Ultra-Fine, Nano Grade Solid Carbide for maximum tool strength and durability
  • Produced from Premium Solid Carbide for maximum rigidity.
  • Standard cutter diameters from .078″ – .500″.
  • Manufactured in house.
  • 2L keeps 1,000s of tools in stock, ready to ship.

Both the Armor Mill and Armor Drill can be used to drill out broken taps and drills. Choice of which tool will rely on your application. Please review the below details for more information.

How to Use Armor Drills – view details.
How to Use Armor Mills – view details.

See all available tool sizes and purchase Armor Drills and Armor Mills here.

Armor Drills – Broken Tap Removal Tool

How to Remove Broken Taps and Drills

Armor Drills Broken Tap Removal Tools

Use an Armor Drill when the tap or drill is broken off above the surface of the workpiece or when the broken tap or drill has a flat top surface that will not cause the drill tip to walk or deflect.

  • It is recommended to use in a rigid machine (machining centers, kneemills, and lathes) with the parts held securely.
  • Use of coolant is typically recommended and will extend the life of the tool bit.
  • Using the handwheel at the lowest speed, feed very slowly and keep a steady feedrate until the tool has plunged far enough into the broken tool to encounter a stable cutting condition. In other words, as the tool begins cutting into the uneven jagged surface of the broken tool, feed extremely slowly to prevent the tool from walking which will put high side loads on the cutting tool and lead to breakage.
  • It is important to prevent the tools from walking or deflecting, especially when first contacting the uneven part surface.
  • Once the tool is fully into the cut and seems stable, feeding with the cnc control at the noted feeds and speeds is possible.
  • Peck or stop frequently to remove chips from the hole.
  • If the part needs to be drilled with a hand drill, operate the drill at faster rpms, use a strong, steady force, and keep the drill as straight as possible.
  • Note: Consider the noted feeds and speeds as a reference point. Variations in the table may be required depending on material being machined and cutting conditions. In particular, stone such as granite and marble have different machining properties among different varieties and even at different spots within the same piece of stone
  • See all available tool sizes and purchase Armor Drills here.

Please note as with all machining, it is important to take appropriate safety precautions.

RPM= Spindle Speed
D = Diameter of tool
IPR = Inches per rev
IPM = Inches per minute
IPT = Inches per tooth
SFM and SFPM = Surface feet per minute 

Material Recommended Speed
(SFPM) and Feedrates (IPT)
Cutter Diameter = .078″ Cutter Diameter = .125″
Granite
Stone
50- 125 SFPM
0.0001 – 0.0005 IPT
1500-2500 RPM
F5.0 IPM
Plunge = 1.5 IPM
1500-2500 RPM
F6.0 IPM
Plunge = 1.5 IPM
Broken Taps and Drills
Armor Plate
Hardened Steel and Drills
50- 125 SFPM
0.0001 – 0.0005 IPT
1500-2500 RPM
Plunge = 0.1 IPM
1500-2500 RPM
Plunge = 0.1 IPM
Copyright © 2021, 2L inc., www.2Linc.com
D taps 1

Armor Drill: Step 1

  • Remove excess drill/tap material to create as flat a surface as possible.
D taps 2

Armor Drill: Step 2

  • Spot drill the broken tap with the largest dia. Armor Drill.
  • Drill at 1,200-2,500 RPM.
D taps 3

Armor Drill: Step 3

  • Drill down through the broken tap.
  • Use coolant if possible.
  • Peck and flush out chips with air blast.
  • Remove remnants of broken tap with pick.

Armor Mills – Broken Tap Removal Tools

How to Remove Broken Taps and Drills

Armor Mills Machine Granite, Hard Materials

Armor Mills can be used when the tap or drill is broken off below the surface of the workpiece or when the broken tap or drill has an uneven top surface tat would cause the tool tip to walk or deflect.

Details & Speeds and Feeds:

  • It is recommended to use the Armor Mill in a rigid machine (machining centers, kneemills, and lathes) with the parts held securely.
  • Using the handwheel at the lowest speed, feed very slowly and keep a steady feedrate until the tool has plunged far enough into the broken tool to encounter a stable cutting condition. In other words, as the tool begins cutting into the uneven jagged surface of the broken tool, feed extremely slowly to prevent the tool from walking which will put high side loads on the cutting tool and lead to breakage.
  • It is important to prevent the tools from walking or deflecting, especially when first contacting the uneven part surface.
  • Once the tool is fully into the cut and seems stable, feeding with the cnc control at the noted feeds and speeds is possible.
  • Peck or stop frequently to remove chips from the hole.
  • If the part needs to be drilled with a hand drill, operate the drill at faster rpms, use a strong, steady force, and keep the drill as straight as possible.
  • Use of coolant is typically recommended and will extend the life of the tool bit.
  • Note: Consider the noted feeds and speeds as a reference point. Variations in the table may be required depending on material being machined and cutting conditions. In particular, stone such as granite and marble have different machining properties among different varieties and even at different spots within the same piece of stone.
  • See all available tool sizes and purchase Armor Mills here.

Please note as with all machining, it is important to take appropriate safety precautions.

RPM = (SFPM x 3.82) / D
IPM = (No. of teeth) x IPT x RPM
RPM= Spindle Speed
D = Diameter of tool
IPR = Inches per rev
IPM = Inches per minute
IPT = Inches per tooth
SFM and SFPM = Surface feet per minute

Material Recommended Speed
(SFPM) and Feedrates (IPT)
Cutting the Shown Piece of Granite, 2L used:
Cutter Diameter = .078″
Depth of Cut per pass = .020″
Cutter Diameter = .125″
Depth of Cut per pass = .030″
Granite
Stone
Armor Plate
Steel
50- 125 SFPM
0.0001-0.001 IPT
6000 RPM
F5.0 IPMPlunge = 2.0 IPM
6000 RPM
F6.0 IPMPlunge = 2.0 IPM
Broken Taps and Drills 50- 125 SFPM
0.0001-0.0005 IPT
1500-2500 RPM
Plunge = 0.1 IPM
1500-2500 RPM
Plunge = 0.1 IPM
Copyright © 2021, 2L inc., www.2Linc.com
A taps 1

Armor Mill: Step 1

  • If possible, use a punch to make the top surface of the broken tap/drill flat before drilling.
A taps 2

Armor Mills: Step 2

  • Drill at 1,200-2,500 RPM.
  • Feed extremely slow (especially when first contacting uneven surface).