YINGBA · CARBIDE CNC CUTTING TOOLS
Step Countersink Drills
One tool for the pilot hole and the countersink in aluminium and plastics.
4.1 mm cutting Ø · 1 and 2 flute · 8 mm shank
Quick answer: a step countersink drill cuts a pilot hole and its countersink in a single operation, which keeps the two diameters concentric and saves a tool change. It is used on aluminium plate and aluminium signage, acrylic, PVC, nylon, POM and composite panels where a flush fastener or a deburred hole is required.
Materials and machines
- Materials: Pure aluminium, aluminium plate and profile, aluminium sign plate, acrylic, PVC, nylon, POM, MDF and plywood
- Machines: Advertising CNC engraving machines, CNC nesting routers, CNC engraving-milling machines, edge trimming machines
Feed rate, spindle speed and depth of cut must be matched to the tool diameter, material, machine rigidity and workholding. These are application-specific and are confirmed for each order.
Complete size list
Available in one-flute and two-flute versions with the same cutting diameter.
Step countersink drill
The pilot and countersink are ground on one body, so the hole and the seat stay concentric.
| Shank (mm) | Cutting Ø (mm) | Flutes | Cutting length (mm) | Overall length (mm) |
|---|---|---|---|---|
| 8 | 4.1 | 1 | 6 | 80 |
| 8 | 4.1 | 2 | 6 | 80 |
Frequently asked questions
What is a step countersink drill used for?
Cutting a pilot hole and its countersink in one pass so a fastener sits flush, and so the hole is deburred. It is used on aluminium, aluminium signage and plastics.
Why use a step drill instead of two separate tools?
It keeps the pilot and the countersink concentric and removes a tool change, which improves repeatability on production runs.
Single flute or two flute?
A single flute clears chips fastest and is useful in gummy plastics; a two-flute version gives a stronger cut and a cleaner seat at higher feed.
Which materials is it specified for?
Pure aluminium, aluminium plate and profile, aluminium sign plate, acrylic, PVC, nylon, POM, MDF and plywood.
Can I order a different countersink diameter?
Yes. Cutting diameter, step geometry and overall length can be produced to your drawing.
Related guides and tools
Need a matched tool recommendation?
Tell us the material, the operation and your machine. YINGBA will review the requirement and prepare a B2B quotation.