Buy Metric Spiral Flute Taps Online in Australia
Metric Spiral Flute Tap Selection — Quick Reference
Spiral flute taps are designed for BLIND HOLES — helix angle of flutes LIFTS CHIPS back up + out of hole instead of packing them at the bottom. Critical where through-tap can't pass through (blind hole) + standard spiral-point tap can't be used. Workshop standard for blind threading.
| Spiral Flute Spec | Best For |
|---|---|
| HSS Standard Spiral Flute | Mild + low-alloy steel blind holes — workshop default |
| HSS Cobalt Spiral Flute (M35/M42) | Stainless + tough alloys blind holes |
| TiN-Coated Spiral Flute (Gold) | Extended life + production blind tapping |
| TiCN / TiAlN Coated | Production + harder materials |
| Metric Coarse Sizes (M3-M16+ typical) | Standard workshop range |
| Metric Fine Sizes (Mf) | Precision + fine-thread blind holes |
| Plug Tap (Blind Hole Bottoming) | Finishes thread to bottom of blind hole |
| Intermediate Tap (Through-Hole) | Standard chamfer — through holes |
Critical difference vs spiral POINT tap: Spiral POINT taps eject chips FORWARD (through-hole only); Spiral FLUTE taps lift chips BACKWARD (blind holes). DON'T USE spiral point in blind holes — chips pack the bottom + jam the tap. DON'T USE spiral flute in through holes — chips can't eject forward + slow cutting. Match flute geometry to hole type. Brands: Sutton Tools, Bordo, OSG. Companion: all taps, threading, metric spiral point taps, metric straight flute taps, threading tap chart.
Metric Spiral Flute Taps
Spiral flute taps are the right choice for cutting threads in blind holes — the helix angle of the flutes lifts chips back up and out of the hole, instead of packing them down at the bottom where they jam the tap and ruin the thread. AIMS Industrial stocks metric spiral flute taps for fitters, machinists, and toolmakers working in steel, stainless, alloy, and non-ferrous materials.
Why spiral flute taps
- Blind holes — chips evacuate up and out, not down into the bottom of the hole
- Soft and gummy materials — the helix shears the chip rather than tearing it, giving a cleaner thread
- Powered tapping — better suited to CNC and tapping head use than straight-flute hand taps
- Aluminium, copper, and stainless — long, stringy chips that would clog a straight-flute tap clear easily through a spiral
Sizes and pitches
We stock metric coarse from M2 to M24, plus the common metric fine pitches (M8×1, M10×1, M10×1.25, M12×1.25, M12×1.5, M14×1.5, etc.). Helix angles vary by application — 15°-25° for general steel, 35°-45° for aluminium and other long-chip materials.
Brands and coatings
The range includes Sutton Tools, Bordo, and Champion in HSS and HSS-E (cobalt) grades. Coating options include bright (general purpose), TiN (extended life in steel), TiCN (harder steels), and TiAlN (high-temperature work in tough alloys).
Tapping practice
Match the helix angle to the material, drill to the correct tapping drill size, and use a quality tapping fluid (Molycut, Tap Magic). Spiral flute taps prefer to be driven by a tapping head or CNC — they're not as forgiving as straight-flute taps in a hand wrench.
Helix angle — match it to the material
The helix angle of the flutes drives chip evacuation. Low-helix taps (15-25°) suit harder, short-chip materials like medium-carbon steel and stainless. Medium-helix (25-35°) is the all-rounder for general workshop use. High-helix (35-45°) is for long-chip, gummy materials like aluminium, copper, and softer alloys — the steeper helix lifts chips out fast before they pack and jam. If your work mix is heavily one material, match the tap to it; if it's varied, medium-helix covers most of the work.
Coatings worth paying for
TiN-coated HSS spiral flute taps roughly double tap life in steel over uncoated. TiCN handles harder steels above 35 HRC. TiAlN and AlTiN are the right call for stainless and tough alloys at higher cutting speeds. For low-volume general work, uncoated HSS-E (cobalt) is often the most economical balance.
Choosing the right tap
Not sure whether your application needs spiral flute or spiral point? contact our team — we'll talk through hole type, material, and operation to get you the right tap first time.