Chatterless Countersinks™

6-Flute Design Eliminates Harmonics for Smooth Countersinking

Jump to: Single Flute 6-Flute HSS 6-Flute Carbide Double-Ended Threaded Shank Heavy Duty Multi-Flute

The Chatter-Free Difference

Traditional single-flute countersinks create harmonics that cause chatter marks. Our 6-flute design eliminates this problem.

Severance Chatterless Countersinks feature a patented 6-flute design with unequal spacing that breaks up the harmonic patterns responsible for chatter. The result is smooth, burr-free countersinks with excellent surface finish - even in interrupted cuts and difficult materials.

Traditional Countersinks
  • Single flute creates harmonics
  • Chatter marks on surface
  • Rough finish, burrs
  • Tool grabbing in soft materials
Chatterless Design
  • 6 flutes break up harmonics
  • Smooth, mark-free finish
  • Clean, burr-free edges
  • Controlled cutting action
Severance Chatterless Countersinks - 6-Flute Design
Available Angles

Countersinks available in standard included angles:

  • 60° (30° per side)
  • 82° (41° per side) - Standard
  • 90° (45° per side)
  • 100° (50° per side)
  • 110° (55° per side)
  • 120° (60° per side)
Pro Tip

82° included angle is the standard for flat-head machine screws in the USA. Use 90° for metric applications.

Single Flute Countersinks

Single Flute Countersink diagram

Economical option for light-duty applications. Single flute design with pilot for accurate hole centering.

Body Dia. Pilot Dia. Angle Shank HSS EDP
1/4" #30 82° 1/4" 02700
5/16" #21 82° 1/4" 02701
3/8" #10 82° 1/4" 02702
1/2" F 82° 1/4" 02703
5/8" 17/64" 82° 3/8" 02704
3/4" 21/64" 82° 3/8" 02705

6-Flute HSS Chatterless Countersinks

6-Flute HSS Chatterless Countersink diagram

Premium M2 high-speed steel countersinks with the original 6-flute chatterless design. Standard 82° included angle.

82° Included Angle (Standard)

Body Dia. Shank Dia. OAL Tool Name HSS EDP
1/8" 1/8" 1-1/2" CS-125-82 02800
3/16" 3/16" 1-3/4" CS-187-82 02801
1/4" 1/4" 2" CS-250-82 02802
5/16" 5/16" 2-1/4" CS-312-82 02803
3/8" 3/8" 2-1/2" CS-375-82 02804
1/2" 1/2" 2-3/4" CS-500-82 02805
5/8" 1/2" 3" CS-625-82 02806
3/4" 1/2" 3-1/4" CS-750-82 02807
1" 1/2" 3-1/2" CS-1000-82 02808
1-1/4" 1/2" 4" CS-1250-82 02809
1-1/2" 3/4" 4-1/4" CS-1500-82 02810
2" 3/4" 4-1/2" CS-2000-82 02811
3" 1" 5" CS-3000-82 02812

90° Included Angle

Body Dia. Shank Dia. OAL Tool Name HSS EDP
1/4" 1/4" 2" CS-250-90 02820
3/8" 3/8" 2-1/2" CS-375-90 02821
1/2" 1/2" 2-3/4" CS-500-90 02822
3/4" 1/2" 3-1/4" CS-750-90 02823
1" 1/2" 3-1/2" CS-1000-90 02824

100° Included Angle

Body Dia. Shank Dia. OAL Tool Name HSS EDP
1/4" 1/4" 2" CS-250-100 02830
3/8" 3/8" 2-1/2" CS-375-100 02831
1/2" 1/2" 2-3/4" CS-500-100 02832
3/4" 1/2" 3-1/4" CS-750-100 02833
1" 1/2" 3-1/2" CS-1000-100 02834

6-Flute Carbide Chatterless Countersinks

6-Flute Carbide Chatterless Countersink

Solid carbide construction for maximum tool life in abrasive materials and high-volume production. 10-20x longer life than HSS in most applications.

82° Included Angle - Carbide

Body Dia. Shank Dia. OAL Tool Name Carbide EDP
1/8" 1/8" 1-1/2" CSC-125-82 03000
3/16" 3/16" 1-3/4" CSC-187-82 03001
1/4" 1/4" 2" CSC-250-82 03002
5/16" 5/16" 2-1/4" CSC-312-82 03003
3/8" 3/8" 2-1/2" CSC-375-82 03004
1/2" 1/2" 2-3/4" CSC-500-82 03005
5/8" 1/2" 3" CSC-625-82 03006
3/4" 1/2" 3-1/4" CSC-750-82 03007
1" 1/2" 3-1/2" CSC-1000-82 03008

90° Included Angle - Carbide

Body Dia. Shank Dia. OAL Tool Name Carbide EDP
1/4" 1/4" 2" CSC-250-90 03020
3/8" 3/8" 2-1/2" CSC-375-90 03021
1/2" 1/2" 2-3/4" CSC-500-90 03022
3/4" 1/2" 3-1/4" CSC-750-90 03023
1" 1/2" 3-1/2" CSC-1000-90 03024

Double-Ended Countersinks

Double-Ended Countersink diagram

Two countersinks in one tool - when one end wears, flip it around for a fresh cutting edge. Economical for high-volume shops.

Body Dia. Angle OAL Tool Name HSS EDP
1/4" 82° 2-1/4" CSDE-250-82 02850
3/8" 82° 2-1/2" CSDE-375-82 02851
1/2" 82° 2-3/4" CSDE-500-82 02852
3/4" 82° 3-1/4" CSDE-750-82 02853
1/4" 90° 2-1/4" CSDE-250-90 02860
3/8" 90° 2-1/2" CSDE-375-90 02861
1/2" 90° 2-3/4" CSDE-500-90 02862

Threaded Shank Countersinks

Threaded Shank Countersink diagram

Threaded shank design for use with countersink holders and quick-change systems. Secure clamping prevents slippage.

Body Dia. Thread Size Angle Tool Name HSS EDP
1/4" 1/4-28 82° CSTS-250-82 02880
5/16" 1/4-28 82° CSTS-312-82 02881
3/8" 1/4-28 82° CSTS-375-82 02882
1/2" 3/8-24 82° CSTS-500-82 02883
5/8" 3/8-24 82° CSTS-625-82 02884
3/4" 1/2-20 82° CSTS-750-82 02885
1" 1/2-20 82° CSTS-1000-82 02886

Heavy Duty Countersinks

Heavy Duty Countersink diagram

Extra-robust construction for demanding applications. Larger shank diameters and increased flute depth for aggressive material removal.

Body Dia. Shank Dia. Angle OAL HSS EDP Carbide EDP
1/2" 1/2" 82° 3" 02900 03050
5/8" 5/8" 82° 3-1/4" 02901 03051
3/4" 5/8" 82° 3-1/2" 02902 03052
1" 3/4" 82° 4" 02903 03053
1-1/4" 3/4" 82° 4-1/4" 02904 03054
1-1/2" 1" 82° 4-1/2" 02905 03055
2" 1" 82° 5" 02906 03056

Multi-Flute Countersink Sets

Complete sets of our most popular countersinks in convenient storage cases.

5-Piece HSS Set

Contains 1/4", 3/8", 1/2", 3/4", and 1" countersinks in 82° angle.

EDP: 02950

5-Piece Carbide Set

Contains 1/4", 3/8", 1/2", 3/4", and 1" carbide countersinks in 82° angle.

EDP: 03080

4-Flute Chatter-Free® Econo-Sinks®

An economical alternative to our 6-flute countersinks, the 4-Flute Econo-Sinks provide excellent chatter-free performance at a lower cost. Ideal for general-purpose countersinking applications.

4-Flute Econo-Sink
Features:
  • 4-flute chatter-free design
  • Economical pricing for high-volume applications
  • Available in HSS and Carbide
  • Standard angles: 82° and 90° included
  • Sizes from 1/4" to 1" diameter
Head Dia. Shank Dia. Angle HSS EDP Carbide EDP
1/4"1/4"82°0260002650
3/8"1/4"82°0260202652
1/2"1/4"82°0260402654
5/8"3/8"82°0260602656
3/4"3/8"82°0260802658
1"1/2"82°0261002660

Chatter-Free® Stop-Countersink Cutters

Stop-Countersink Cutters provide precise depth control for consistent countersink dimensions. The built-in stop collar ensures repeatable results without the need for depth setting adjustments.

Stop-Countersink Cutter
Features:
  • Built-in depth stop for consistent countersink depth
  • Chatter-free cutting action
  • Available for specific screw sizes (#4 through 1/2")
  • HSS and Carbide options
  • Ideal for production environments requiring repeatability

HSS Stop-Countersink Cutters

Screw Size Body Dia. Pilot Dia. 82° EDP 100° EDP
#41/4".1120240002420
#65/16".1400240202422
#83/8".1640240402424
#107/16".1900240602426
1/4"1/2".2500240802428
5/16"5/8".3120241002430
3/8"3/4".3750241202432
1/2"1".5000241402434

Micrometer Stop Countersink Units

Precision micrometer-adjustable stop units allow for exact depth control in countersinking operations. The micrometer collar provides fine adjustment for perfect countersink depth every time.

Micrometer Stop Unit
Features:
  • Micrometer adjustment for precision depth control
  • Accepts standard countersink cutters
  • Graduated collar for easy depth reading
  • Spring-loaded for consistent pressure
  • Available in multiple shank sizes
Unit Size Shank Dia. Max Cutter Dia. EDP Number
SC-241/4"1/2"02500
SC-413/8"3/4"02502
SC-423/8"1"02504
SC-471/2"1"02506
SC-571/2"1-1/2"02508
SC-635/8"2"02510
SC-823/4"2-1/2"02512

Adjustable Drill Countersinks

Combination drill and countersink tools that allow adjustment for different screw sizes and countersink depths. One tool handles multiple fastener sizes, reducing tool changes and setup time.

Adjustable Drill Countersink
Features:
  • Adjustable for multiple screw sizes
  • Combination drill and countersink in one tool
  • Set screw locks drill in position
  • Accepts standard twist drills
  • 82° and 100° included angles available

Note: Drills sold separately. Accepts standard jobber length drills.

Body Dia. Drill Range Shank Dia. 82° EDP 100° EDP
3/8"#1 - #101/4"0230002320
1/2"#10 - 1/4"3/8"0230202322
5/8"1/4" - 5/16"3/8"0230402324
3/4"5/16" - 3/8"1/2"0230602326
1"3/8" - 1/2"1/2"0230802328

Technical Data & Speed/Feed Recommendations

Chatterless Countersinks perform best at moderate speeds with consistent feed rates. The 6-flute design allows for higher feed rates than conventional countersinks while maintaining a smooth finish.

HSS Countersinks
Material RPM (1/2" dia) Feed IPR
Aluminum 2000-3000 .003-.006"
Brass/Bronze 1500-2500 .002-.004"
Mild Steel 500-1000 .002-.003"
Stainless Steel 300-600 .001-.002"
Carbide Countersinks
Material RPM (1/2" dia) Feed IPR
Aluminum 4000-6000 .004-.008"
Brass/Bronze 3000-5000 .003-.005"
Mild Steel 1000-2000 .002-.004"
Stainless Steel 600-1200 .001-.003"
Why Chatterless?

Traditional 4-flute countersinks create harmonic vibrations that cause chatter marks on the countersink surface. The 6-flute Chatterless design interrupts these harmonics, producing smooth, professional finishes even at higher feed rates. This allows for faster cycle times without sacrificing quality.

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Need a Custom Countersink Solution?

We manufacture custom angles, sizes, and configurations. Contact our engineering team for a quote.

Contact Us 989-777-5500