Tap Sets

Tap Sets — Metric, UNC, UNF & BSP Threading Tools for Workshop & Trade

AIMS Industrial stocks a comprehensive range of tap sets for cutting internal threads in steel, aluminium, cast iron, and engineering plastics. Our range from Sutton Tools, Bordo, Goliath, and P&N covers Metric, UNC, UNF, BSPF, and BSW thread forms — in hand tap sets, straight flute machine tap sets, and taper/intermediate/bottoming combinations for hand tapping and CNC applications.

Tap Set Types & Thread Standards

• Metric Straight Flute Tap Sets (ISO529): Sutton Tools T901 Metric HSS straight flute tap sets are manufactured to ISO529 dimensions — covering M3 to M12 metric coarse pitch in a complete range set for engineering workshop and maintenance use.
• Metric Hand Tap Sets (Taper/Int/Bottom): Sutton Tools M203 and M243 metric hand tap sets include all three tap styles (taper, intermediate, and bottoming) for complete through-hole and blind-hole threading — tungsten chrome construction for extended tool life in steel and cast iron.
• UNC Tap Sets: Sutton Tools T903 UNC (Unified National Coarse) straight flute tap sets cover imperial coarse thread forms for maintenance of American-standard fastener threads in imported equipment, tooling, and machinery.
• UNF Tap Sets: Sutton Tools T904 UNF (Unified National Fine) tap sets are designed for fine-pitch imperial threads where higher tensile strength and vibration resistance are required — typical in aerospace, automotive, and precision instrument applications.
• BSP & BSW Tap Sets: Sutton Tools BSPF and BSW hand tap sets cover British Standard Pipe and Whitworth thread forms — essential for maintenance and repair of older Australian and UK-origin plant, hydraulic fittings, and fluid system components.
• Bordo & Goliath Tap Sets: Bordo and Goliath metric and imperial tap sets provide alternative sizing and value options — stocked for workshop replenishment and trade use across a full range of thread standards.

Tap Set Selection & Tapping Technique

• Tap Type for Application: Taper taps start the thread and are used first in through-holes; intermediate taps continue threading; bottoming taps cut to the base of blind holes where full thread depth is required. Use all three in sequence for blind-hole threading.
• Thread Pitch Selection: Always verify metric coarse vs. fine pitch, and imperial TPI, before selecting a tap — mismatched tap pitch on existing threads destroys the thread form and may require helicoil insertion to recover the fastener hole.
• Cutting Speed & Lubrication: Use tapping compound or cutting fluid on all HSS taps — dry tapping in steel dramatically shortens tap life and risks tap breakage. In aluminium, a light oil or kerosene/oil mix prevents built-up edge on tap flutes.
• Drill Size Compatibility: Always use the correct drill size for the selected tap — under-drilling leaves insufficient material removal room and breaks taps; over-drilling produces undersized, weak threads. Drill size charts are available from Sutton Tools for all thread standards.

Australian Business, Local Supply: As a proudly Australian business since 1988, we stock locally and work with trusted local Australian manufacturers and distributors to ensure fast, reliable supply.

Shop the full range above, or contact our team for expert advice on the right product for your application or reach out if you need a quote. Fast dispatch from our Australian warehouse.

People Also Ask — Tap Sets

Q: What's in a typical hand tap set?

A standard tap set covers a range of thread sizes in 3-tap configurations: taper tap (starts the thread), plug tap (cuts the working portion), bottoming tap (finishes close to the bottom of blind holes). Metric workshop sets typically cover M3 through M12 or M16 in coarse pitch. Imperial sets cover UNC, UNF, or both. Specialty sets add metric fine, BSP/NPT, BSW/BSF as needed.

Q: Do I need taper, plug, and bottoming taps for every job?

Only for blind holes where you need to thread close to the bottom. For through holes, a plug tap alone usually works — the taper of the plug tap's first few threads provides enough lead-in for hand-driven work. For machine work (drill press, mag drill, CNC), spiral point taps replace the 3-tap hand set entirely — single tap, through holes only. Blind hole machine work uses spiral flute taps.

Q: What's the difference between HSS, HSS-Cobalt, and HSS-Powder Metal taps?

HSS handles mild steel, aluminium, brass, and general workshop materials. HSS-Cobalt (M35 5% Co, M42 8% Co) handles stainless steel and tougher alloy steels at HSS speeds. HSS-Powder Metal (HSS-PM, ASP series) gives the toughness of HSS with the hot hardness of cobalt — used in production threading of difficult materials. For workshop kit, HSS-Cobalt covers most non-trivial materials cost-effectively.

Q: Why do my taps keep breaking?

Common causes: wrong tap drill (too small — excessive torque on the tap), tap not started square to the work, no cutting fluid (heat builds in the cutting edges), spiral point tap in a blind hole (chips pack and snap), chip not broken regularly during hand tapping (chip jams), or tap dull from prior heavy use. Check the tap drill size against the chart, use cutting fluid, and back the tap off every 1/4 turn to break chips.

Q: What tap set covers a general workshop?

Metric coarse M3-M12 in 3-tap hand sets handles 80% of general assembly and repair work. Add metric M14, M16, M20 if you work on larger equipment. UNC and UNF in 1/4-inch through 1-inch handle imperial-spec automotive and US-origin equipment. BSP 1/8 to 1/2 inch handles plumbing and pneumatic work. Stocking taps in HSS-Cobalt rather than plain HSS adds modest cost and dramatically extends life in stainless work.