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Carmex Carbide Threading Insert - Whitworth - TiAlN Coated - 21-20W
| Application | Threading |
| Thread Form | WHIT (BSW BSF BSP) |
| Internal or External | Internal & External |
| Insert Size | 21 |
| Pitch | 20 |
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The Carmex Carbide Threading Insert in Whitworth form is a durable, TiAlN-coated solution for machinists who regularly cut Whitworth threads and other common profiles. Designed for versatility, it handles both internal and external threading tasks with dependable precision.
- Model/Coating: TiAlN-coated carbide insert from Carmex, built for strength and heat resistance in demanding threading operations.
- Thread profiles: Covers all common thread profiles, with reliable performance on Whitworth forms.
- Length options: Available in 5 lengths from 12 mm to 40 mm to fit a wide range of setups and pitches.
- Pitch range: Suitable for pitches from 0.5 mm (32 TPI) up to 6.0 mm (4 TPI), enabling both fine and coarse thread work.
- Double-edged design: Inserts are double-sided with two cutting edges (except for BSPT/NPT/NPTF/American Buttress/API RD), improving tool life per edge.
- Internal/External capability: For many thread profiles, the same insert can machine both internal and external threads (with noted exceptions for ISO/UN/NPSM/UNJ/Acme).
This threading insert delivers practical, real-world benefits: extended tool life from a hard carbide with a resilient TiAlN coating, reduced downtime thanks to dual cutting edges, and the flexibility to tackle a broad spectrum of thread forms without swapping inserts. Its design focuses on reliability and consistency, helping you achieve accurate thread profiles across a range of materials and applications.
| Application | Threading |
| Thread Form | WHIT (BSW BSF BSP) |
| Internal or External | Internal & External |
| Insert Size | 21 |
| Pitch | 20 |
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: Carmex Carbide Threading Inserts - Whitworth - TiAlN Coated
View full collection →You are viewing 21-20W. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| 12-19W | 12 | 19 | £26.50 | 5 days | |
| 14-11W | 14 | 11 | £34.92 | In Stock | |
| 14-14W | 14 | 14 | £26.50 | In Stock | |
| 14-16W | 14 | 16 | £26.50 | In Stock | |
| 14-19W | 14 | 19 | £26.50 | In Stock | |
| 14-20W | 14 | 20 | £26.50 | In Stock | |
| 14-24W | 14 | 24 | £26.50 | In Stock | |
| 21-11W | 21 | 11 | £35.22 | In Stock | |
| 21-14W | 21 | 14 | £35.22 | In Stock | |
| 21-16W | 21 | 16 | £35.22 | In Stock | |
| 21-19W | 21 | 19 | £35.22 | In Stock | |
| 21-20W Viewing | 21 | 20 | £35.22 | In Stock | |
| 30-11W | 30 | 11 | £48.30 | In Stock | |
| 30-14W | 30 | 14 | £48.30 | In Stock | |
| 30-16W | 30 | 16 | £48.30 | In Stock | |
| 40-11W | 40 | 11 | £83.54 | 5 days | |
| 40-8W | 40 | 8 | £83.54 | 5 days |
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