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Carmex Carbide Threading Insert - Whitworth - TiAlN Coated - 21-20W

SKU:21-20W

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, i... Read more ↓
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ApplicationThreading
Thread FormWHIT (BSW BSF BSP)
Internal or ExternalInternal & External
Insert Size21
Pitch20
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£35.22
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In Stock— only 4 left
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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.

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Staff are very helpful and polite.Goods that were in stock were dispatched same day and back orders were quick in coming through .
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Phone requests are handled quickly and without any fuss. The website is easy to use and straightforward to order from. It’s especially helpful that it shows real‑time availability, so we don’t need to call to confirm whether parts will arrive.
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Full Range: Carmex Carbide Threading Inserts - Whitworth - TiAlN Coated

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You are viewing 21-20W. Click any other SKU to view its full details.

Product SKUInsert SizePitchPriceStock Order
12-19W 1219£26.50 5 days
14-11W 1411£34.92 In Stock
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14-24W 1424£26.50 In Stock
21-11W 2111£35.22 In Stock
21-14W 2114£35.22 In Stock
21-16W 2116£35.22 In Stock
21-19W 2119£35.22 In Stock
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40-11W 4011£83.54 5 days
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