How to read a carbide micro drill part number
A part number on a drawing should be enough to rebuild the tool. Ours follow a fixed pattern, and the production catalogue holds 11,717 of them.
The pattern
SERIES-DIAMETER-SUFFIX
| Part of the code | Meaning | Example |
|---|---|---|
| Prefix | Grinding series | DC426 |
| Four digits | Cutting diameter in thousandths of a millimetre | 1000 = 1.000 mm |
| Suffix | Flute, coating or customer variant | 04 |
So DC426-1000-04 is a black-coated solid carbide drill with a 1.000 mm cutting diameter.
The geometry callout
Every part number also carries a dimensional string:
D1 * flute length * shank diameter * overall length * point angle
For the example above the record reads D1.00*7*3*38: 1.00 mm cutting diameter, 7 mm flute, 3 mm shank and 38 mm overall length. All values are in millimetres.
When the string is longer
Step drills and multi-diameter tools do not fit four numbers. Their callout is reproduced verbatim, for example D1.45*3.7*120°+1.85*4.0*70°*3*38. We do not simplify it into a single diameter, because that is exactly the information an engineer needs.
If a code on your drawing does not resolve in the lookup, send the string. We will identify the nearest standard geometry or confirm it is a custom grind.
The catalogue is filterable by family, series code, coating and diameter band, so you can check whether a neighbouring diameter already exists before asking for a custom programme.