Drill, Tap and Die

Resources for selecting metal drill bits for your project.

Practical Summary: https://www.youtube.com/watch?v=9r-4nuaBsQA

  • Use TiN coated drills for milk steel and aluminum.

  • TiCN coated drills for cast iron.

  • Use TiAlN coated drills for hardened steels

  • Cobalt and carbide drills are ground with self-centering points so there is no need to spot drill with cobalt and carbide.

  • HSS drills can only drill 2-3 times the drill diameter before switching to peck drilling.

  • Carbide drills can drill up to 5x the drill diameter before needing to peck drill.

  • When drilling a hole 8 times deeper than the diameter, engage the metal at a slower speed. Then speed up the bit

  • Sharpen your drill bits when the holes start to go out of tolerance and the wear and chipping are below .02”

Titanium Drill Bit Set

230 pc titanium drill bit set 3/16” to 1/2”, Wood, Cast Iron, Aluminum Alloy, Plastic: https://amzn.to/3DSv1mp

Cobalt Drill Bit Set

115 pc Cobalt drill bits Fractional size 1/16” to 1/2” in 1/64th, Increments for hardened metals, stainless steel, cast iron, wood, plastics: https://amzn.to/4hveumd

Boring Bar for R8

Floating Tap Set

Floating Tap Set Reversible Lathe

Hand Tapping with a Mill or Lathe for Alignment

Hand Tap & Die Sets

Basic Economy Set: https://amzn.to/4lr3BVK

127pc Set W/ Ratchet and Drill Bits: https://amzn.to/4j7culR

Replacement Taps: https://amzn.to/3EjjY62

110pc Metric: https://amzn.to/4jnXIXy

Tapping & Cutting Fluid: https://amzn.to/4cvixy8

Machine/Power Taps

Tap Set (M2-M12) : https://amzn.to/3RifX4M

Titanium Tap Bits SAE (4-40, 6-32, 8-32): https://amzn.to/4lNI4ab

Titanium Tap Bits SAE (3/8-16, 5/16-18, 1/2-13, 5/8-11) : https://amzn.to/4lvH621

HSS Drill Tap Bits Metric & SAE (1/4-20, 3/8-16, 1/2-13, 5/16-18, M4x0.7, M5x0.8, M6x1.0, M8x1.25, M10x1.5): https://amzn.to/4cQKoZX

HSS Combined Drill & Tap Bits Metric & SAE: (6-32, 8-32, 10-24, 10-32, 1/4-20, 1/4-28, 3/8-16, 3/8-24, 5/16-18, 5/16-24, 7/16-14, 7/16-20, 1/2-13, 1/2-20) (M6X1.0, M8x1.25, M10x1.5) https://amzn.to/3RiefjS

Detailed Drill Analysis

Video: https://www.youtube.com/watch?v=sykjB7fS1Po

Summary: Material, Coating & Geometry.

Material

  • HSS: Basic and inexpensive. Forgiving in drill presses and hand drilling. Easy to resharpen.

  • HSS w/Cobalt: Holds up better than HSS. More heat and wear resistance. Easy to re-sharpen.

  • Carbide: Best heat and chip resistance. Allows for coolant through-holes (T.S.C). Carbide can cost 10x more and last 10x longer. Lower cost per hole. Very stiff and less forgiving. Need to know how to use it. Carbide can run faster.

Coating

  • Bright Finish: Cheapest. Can be used on low-carbon steel and aluminum.

  • Black Oxide: More lubricity than bright finish. Resistance to oxidation. Heat treatment offering 50% longer life.

  • Titanium Nitride: Most common. Great entry-level coating. Not meant for hard materials and high heat transfer. Is bright gold color.

  • Titanium Carb Nitride: Step up from TiN. Higher performing. Slightly harder, better wearing than TiN. blueish or purple in color.

  • Titanium Aluminum Nitride: Higher performing than TiN & TiCN. Higher surface temperatures. Great for steels and stainless steels. Not great for aluminum.

Geometry

  • Length: Stub is preferred for CNC but whatever the shortest needed for the length.

  • Flute length? 2 times the flute diameter above the tope of the hole to allow the chips to escape.

  • Drill point angle: Jobber angle approximately 118 degrees for mild steels, aluminum and other soft metals. Stub length and approximately 135 degrees for hard steels and harder/tough materials in general.

  • Helix Angle: General purpose has a 30 degree angle. Used for most materials. 10 degree angle is for special applications such as harder steels or aluminum alloys to improve chip removal. Larger angles up to 40 degrees are used for difficult materials like stainless steel.

Note 1: We attempt to find the best balance between quality and price. However, many of these parts are made in China and the quality may vary over time. Please check your parts before the return window ends.

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