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OSG Threading Tap - UNF Spiral Flute HSS-E - Steam Oxide Coated - Blind Hole - 1.1/4 x 12

OSG Threading Tap - UNF Spiral Flute HSS-E - Steam Oxide Coated - Blind Hole - 7/16 x 20

SKU:OSG-23204814A

The OSG UNF Spiral Flute Threading Tap is a precision tapping tool designed for blind-hole applications, delivering accurate threads with consistent results. Crafted for demanding metalworking tas... Read more ↓
P
M
FormUNF
Size7/16
Pitch20
Flute Length25
Shank Diameter8
Overall Length85
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£82.22
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1–2 days estimated lead time — subject to availability
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The OSG UNF Spiral Flute Threading Tap is a precision tapping tool designed for blind-hole applications, delivering accurate threads with consistent results. Crafted for demanding metalworking tasks, it combines cobalt-enhanced HSS with a durable steam oxide finish to stand up to higher speeds and tougher materials.

  • Thread Type: UNF (Unified National Fine) with a spiral flute geometry that promotes smooth cutting and efficient chip evacuation in blind holes.
  • Size & Pitch: 7/16-20 UNF, a fine-pitch standard for precise fastener engagement in structural and mechanical assemblies.
  • Material: HSS‑E (high-speed steel with cobalt) for enhanced hardness, heat resistance, and extended tap life.
  • Coating: Steam oxide coating reduces friction, improves heat dissipation, and provides additional protection in challenging workshop environments.
  • Flute Design: Spiral flutes optimize chip removal, minimizing clogging and extending tool life during blind-hole tapping.
  • Applications: Ideal for tapping blind holes in steel, cast iron, and other common metal workpieces where access is limited.

With the OSG UNF Spiral Flute Threading Tap, you can achieve clean, accurate threads quickly and reliably. The cobalt-enhanced steel stands up to higher cutting speeds and temperatures, while the spiral flute and steam oxide coating work together to reduce wear and heat buildup. This makes it a dependable choice for production runs, repairs, and precision assemblies where consistent thread quality and long tool life matter most.

Form UNF
Size 7/16
Pitch 20
Flute Length 25
Shank Diameter 8
Overall Length 85
Substrate HSS-E
Style Spiral Flute

What time are Protool open?

We are open Monday to Friday between 8:30am and 5pm.

Do you offer Free Next Day delivery?

Yes! We offer Free Next Day delivery via Royal Mail Tracked 24 on all orders over £50 ex VAT*. We also offer Free DPD Local Next Day delivery on all orders over £100 ex VAT*.

We also offer the following:

  • Royal Mail Tracked 24 — £5.90 (FREE on orders over £50 ex VAT*). Order before 4:30pm for next day delivery. No signature required.
  • DPD Local Next Day — £8.00 (FREE on orders over £100 ex VAT*). Standard next day delivery to UK mainland addresses.
  • Royal Mail Special Delivery — £12.50. Guaranteed delivery before 1pm the next working day.
  • DPD Saturday Delivery — £25.00. Must be ordered on Friday before 4pm. Pre-12pm delivery.

For delivery to Scottish Highlands & Islands, Northern Ireland, Republic of Ireland, or overseas locations, additional charges apply. Please see our delivery page for full details, or call us on 01732 887 334.

*T's & C's and exclusions apply. Please see our delivery page for more information on all our services.

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Full Range: OSG Threading Taps - UNF Spiral Flute HSS-E - Steam Oxide Coated - Blind Hole

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You are viewing OSG-23204814A. Click any other SKU to view its full details.

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