Application guide
Carbide micro drilling for CNC machining
For CNC micro drilling, identify the material, hole diameter and depth before choosing a catalogue family. Check the flute length and shank for that size, and specify whether the application requires internal coolant.
Separate the tool families before choosing a size
01
Standard micro drills
The catalogue lists RNT micro drills on 3 mm and 4 mm shanks, with external or through-coolant. Include the actual material grade when requesting a tool.
02
Standard coolant drills
Through-coolant RNT micro drills start at Φ0.6 mm. RNS deep micro drills, from 8xD to 30xD, are all through-coolant.
03
Custom micro through-coolant
Micro through-coolant and other non-standard geometries are reviewed against the application. Send the diameter, depth and coolant requirements rather than assuming a standard combination.
Check diameter, flute length and shank together
The four RNT tables below have different flute lengths and coolant configurations. Read the dimensions as a set, rather than selecting on diameter alone.
| Series | Diameter | Flute length | Shank / OAL |
|---|---|---|---|
| RNT, 3 mm shank, external coolant | Φ0.1–2.9 | 4–10 | 3 / 38 |
| RNT, 3 mm shank, through-coolant | Φ0.6–2.9 | 5–10 | 3 / 38 |
| RNT, 4 mm shank, external coolant | Φ2–4 | 10–20 | 4 / 50 |
| RNT, 4 mm shank, through-coolant | Φ2–4 | 10–20 | 4 / 50 |
Flute lengths differ from one diameter band to the next. Check each pairing in the RNT and RNS micro drill tables, catalog chapter 01 (PDF).
Listed diameter bands do not establish every available ordering increment. Confirm the required diameter and geometry before selecting the tool.
Prepare the small-hole enquiry
- Material grade and hardness, hole diameter, depth and blind or through condition.
- Entry and exit geometry, cross-holes, and the part drawing where available.
- Hole tolerance, surface finish and permitted burr condition.
- Machine and spindle, holder, tool reach and available coolant equipment.
- Batch quantity, current tooling and the issue the new tool needs to address.
For a geometry outside the standard table, use the custom tooling enquiry route. Cutting conditions are reviewed for the actual setup.
Send the small-hole requirements
Include the material, diameter, depth and machine conditions. A drawing helps distinguish the standard options from a custom requirement.