What Materials Can Spot & Chamfer Drills (Custom) Cut? Workpiece Compatibility Guide
September 16, 2026 · Exactalloy Technical Team
The same tool behaves very differently across ISO material groups. Use this table, then confirm with a trial cut.
Quick answer: Spot & Chamfer Drills (Custom) suits ISO P (steel) and M (stainless) best, works in K (cast iron) and N (aluminium) with the right coating, and needs reduced parameters in S (superalloys) and H (hardened).
ISO P — steel
The reference application. Run at the mid to high end of the surface speed range with continuous coolant.
ISO M — stainless steel
Work-hardening demands a positive, sharp geometry and no dwell; keep feed high enough to cut below the hardened layer.
ISO K — cast iron
Free graphite is abrasive; wear-resistant coatings and air blast or dry cutting work best.
ISO N — aluminium
Use a polished edge with high speed and generous chip room; avoid coatings that promote built-up edge.
ISO S / H — superalloys and hardened steel
Reduce surface speed, raise coolant pressure, and accept shorter tool life per edge.
Specifications at a glance
| ISO group | Material | Relative speed | Coolant |
|---|---|---|---|
| P | Carbon / alloy steel | 100 % | Flood / through |
| M | Stainless steel | 60 % | Flood, high pressure |
| K | Cast iron | 110 % | Dry / air blast |
| N | Aluminium | 250 % | Mist / air |
| S | Titanium, Inconel | 35 % | High pressure |
| H | Hardened steel | 45 % | Air or MQL |
Frequently asked questions
Can one tool cover both steel and aluminium?
Physically yes, but coating and edge preparation are optimised per group — expect a compromise.
Do you support trial cutting before volume orders?
Yes, samples are supplied for evaluation on your machine.
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Exactalloy supplies Spot & Chamfer Drills (Custom) from stock, made-to-order and reground. Send your drawing or specification for a quotation and lead time within 24 hours. Contact us or browse all products.