CNC grinding: end mills, drills & special cutters
See how we use a CNC grinder to make carbide end mills, drills and special cutters.
Watch on YouTubeDIN 6537 Standard Sizes · Coolant-Thru Drill Depth Ratio
12D DIN 6537 Carbide Coolant-Thru Drills
These are German DIN 6537 standard-size coolant-through carbide drills. Designed for oil galleries, tie-rod holes, and structural deep-hole features in forged and cast components. The 12D ratio requires precise machine setup (low runout, rigid fixturing) but delivers repeatable hole straightness well beyond what conventional drills can achieve. Internal coolant is essential at this depth.
12xD coolant drilloil gallery drillextra deep hole drillingforged steel deep drill
Applications
Oil galleries · Tie-rod holes · Forged steel parts · Cast housings with long oil passages
Feed-In Method
Start in a prepared pilot hole. Feed carefully through entry, run continuous internal coolant, and avoid peck cycles unless chips prove unstable.
Pilot Hole
Required for reliable entry and straightness. Use a short, high-accuracy pilot drill before the 12D tool.
Coolant Requirement
Internal coolant at 40-60 bar is required. Confirm pump flow and filtration before production.
12D DIN 6537 SKU Range
Complete 12D DIN 6537 Coolant-Thru Drill Sizes
Extra deep — oil passages, tie rods, cast and forged components
| CUTTER DIA (D1) h7 | FLUTE LENGTH (L2) | SHANK DIA (D2) h6 | OVERALL LENGTH (L1) | Price | SKU PAGE | |
|---|---|---|---|---|---|---|
| 3.00 | 0.1181 | 55.00 | 4.00 | 92.00 | $18.37 | Details |
| 4.00 | 0.1575 | 64.00 | 6.00 | 102.00 | $29.30 | Details |
| 5.00 | 0.1969 | 78.00 | 6.00 | 118.00 | $34.66 | Details |
| 6.00 | 0.2362 | 78.00 | 6.00 | 118.00 | $34.66 | Details |
| 7.00 | 0.2756 | 108.00 | 8.00 | 146.00 | $60.99 | Details |
| 8.00 | 0.3150 | 108.00 | 8.00 | 146.00 | $60.99 | Details |
| 9.00 | 0.3543 | 120.00 | 10.00 | 162.00 | $89.67 | Details |
| 10.00 | 0.3937 | 120.00 | 10.00 | 162.00 | $89.67 | Details |
| 11.00 | 0.4331 | 156.00 | 12.00 | 204.00 | $147.47 | Details |
| 12.00 | 0.4724 | 156.00 | 12.00 | 204.00 | $147.47 | Details |
| 13.00 | 0.5118 | 182.00 | 14.00 | 230.00 | $224.23 | Details |
| 14.00 | 0.5512 | 182.00 | 14.00 | 230.00 | $224.23 | Details |
| 15.00 | 0.5906 | 208.00 | 16.00 | 260.00 | $328.78 | Details |
| 16.00 | 0.6299 | 208.00 | 16.00 | 260.00 | $328.78 | Details |
| 17.00 | 0.6693 | 234.00 | 18.00 | 285.00 | $453.65 | Details |
| 18.00 | 0.7087 | 234.00 | 18.00 | 285.00 | $453.65 | Details |
| 19.00 | 0.7480 | 258.00 | 20.00 | 310.00 | $606.54 | Details |
| 20.00 | 0.7874 | 258.00 | 20.00 | 310.00 | $606.54 | Details |
Process Notes
What to Confirm Before Running 12D
Feed-In
Start in a prepared pilot hole. Feed carefully through entry, run continuous internal coolant, and avoid peck cycles unless chips prove unstable.
Pilot Hole
Required for reliable entry and straightness. Use a short, high-accuracy pilot drill before the 12D tool.
Cooling
Internal coolant at 40-60 bar is required. Confirm pump flow and filtration before production.
RFQ Data
Share drawing, required straightness, coolant pressure, fixture condition, material grade, and batch quantity.
RFQ Checklist
Quote 12D DIN 6537 coolant-thru drills faster
- Diameter list and quantities
- Work material and hardness
- Hole depth, blind/through condition, tolerance
- Coolant pressure, filtration, machine/toolholder
- Coating preference and annual quantity
FROM OUR WORKSHOP
Watch us grind and inspect our tools
Two videos filmed in our workshop: CNC tool grinding and dimensional inspection.
Measuring carbide end mills at 0.001 mm
Watch our ZOLLER inspection process for precision carbide end mills.
Watch on YouTube