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OSG Threading Tap - UNC Spiral Flute HSS-E - Steam Oxide Coated - Blind Hole - 5/16 x 18
| Form | UNC |
| Size | 5/16 |
| Pitch | 18 |
| Flute Length | 22 |
| Shank Diameter | 8 |
| Overall Length | 72 |
Learn more about Klarna
The OSG UNC Spiral Flute Threading Tap is a high-performance tool designed for precise blind-hole threading in metalworking projects. Built for machinists who demand reliability, this tap combines advanced materials and coating to deliver accurate threads and extended tool life.
- Size / Thread: 5/16"-18 UNC threading tap for blind-hole applications, optimized for consistent, standard-threaded fasteners.
- Material: HSS-E (high-speed steel with cobalt) for superior wear resistance and heat tolerance during repetitive cuts.
- Coating: Steam Oxide coating enhances durability and corrosion resistance, supporting longer tool life in tough environments.
- Flute design: Spiral flute geometry provides efficient chip evacuation, reducing chip packing in blind holes and improving cutting stability.
- Application: Specifically engineered for threading blind holes in a variety of metals where access is limited and precision matters.
- Brand technology: Leveraging OSG’s advanced threading technology to produce accurate threads with consistent finish and dependable performance.
This tap helps you achieve clean, repeatable threads with minimal rework, even on challenging materials. The combination of HSS-E cobalt and Steam Oxide coating delivers reliable performance under higher cutting temperatures, while the spiral flute design minimizes chip buildup in blind holes. Ideal for critical machining tasks where precision, durability, and extended tool life are essential.
| Form | UNC |
| Size | 5/16 |
| Pitch | 18 |
| Flute Length | 22 |
| Shank Diameter | 8 |
| Overall Length | 72 |
| 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.
Full Range: OSG Threading Taps - UNC Spiral Flute HSS-E - Steam Oxide Coated - Blind Hole
View full collection →You are viewing OSG-22204744. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Flute Length | Shank Diameter | Overall Length | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| OSG-22204534 | No. 2 | 56 | 9.5 | 2.8 | 44.5 | £64.30 | In Stock | |
| OSG-22204554 | No. 3 | 48 | 9.5 | 2.8 | 44.5 | £64.30 | In Stock | |
| OSG-22204574 | No. 4 | 40 | 11 | 3.15 | 48 | £39.97 | In Stock | |
| OSG-22204594 | No. 5 | 40 | 11 | 3.15 | 48 | £39.97 | 1-2 days | |
| OSG-22204614 | No. 6 | 32 | 13 | 3.55 | 50 | £24.13 | In Stock | |
| OSG-22204644 | No. 8 | 32 | 13 | 4.5 | 53 | £24.13 | In Stock | |
| OSG-22204664 | No. 10 | 24 | 16 | 5 | 58 | £24.13 | In Stock | |
| OSG-22204684 | No. 12 | 24 | 17 | 5.6 | 62 | £29.55 | 1-2 days | |
| OSG-22204714 | 1/4 | 20 | 19 | 6.3 | 66 | £20.00 | In Stock | |
| OSG-22204744 Viewing | 5/16 | 18 | 22 | 8 | 72 | £23.19 | In Stock | |
| OSG-22204794 | 3/8 | 16 | 24 | 10 | 80 | £29.55 | In Stock | |
| OSG-22204844 | 7/16 | 14 | 25 | 8 | 85 | £41.11 | In Stock | |
| OSG-22204894 | 1/2 | 13 | 29 | 9 | 89 | £41.63 | In Stock | |
| OSG-22204944 | 9/16 | 12 | 30 | 11.2 | 95 | £53.03 | In Stock | |
| OSG-22205014 | 5/8 | 11 | 32 | 12.5 | 102 | £61.69 | In Stock | |
| OSG-22205154 | 3/4 | 10 | 37 | 14 | 112 | £92.73 | In Stock | |
| OSG-22205264 | 7/8 | 9 | 38 | 16 | 118 | £128.64 | In Stock | |
| OSG-22205384 | 1 | 8 | 45 | 18 | 130 | £154.71 | In Stock | |
| OSG-22205514 | 1.1/8 | 7 | 48 | 20 | 138 | £265.95 | 1-2 days | |
| OSG-22205644 | 1.1/4 | 7 | 51 | 22.4 | 151 | £338.98 | In Stock |
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