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Carmex Carbide Threading Insert - Unified - TiAlN Coated - 21E24UN

SKU:21E24UN

The Carmex Carbide Threading Insert is a unified-thread, TiAlN-coated solution built for machinists and production shops that demand precise, dependable threading across common profiles. Coati... Read more ↓
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ApplicationThreading
Thread FormUN
Internal or ExternalExternal
Insert Size21
Pitch24
Download Cutting Data
£35.22
Prices shown ex. VAT
In Stock— only 5 left
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Mon – Thurs 8:30 – 17:30 · Fri 8:30 – 16:30

The Carmex Carbide Threading Insert is a unified-thread, TiAlN-coated solution built for machinists and production shops that demand precise, dependable threading across common profiles.

  • Coating: TiAlN-coated carbide inserts for enhanced hardness and heat resistance, helping maintain cutting performance in demanding materials.
  • Thread profiles coverage: A versatile collection that covers all common thread forms, designed to minimize tool changes and maximize setup flexibility.
  • Lengths: Five available lengths ranging from 12 mm to 40 mm to suit different workpiece sizes and access needs.
  • Pitch range: Capable of threading pitches from 0.5 mm (32 TPI) to 6.0 mm (4 TPI), enabling a wide array of standard screws and fasteners.
  • Double-sided edges: Each insert provides two cutting edges (double-sided) to extend tool life, with exceptions for BSPT/NPT/NPTF/American Buttress/API RD profiles.
  • Internal/External threading capability: For many thread profiles, the same insert can machine both internal and external threads, reducing tooling complexity—note: ISO/UN/NPSM/UNJ/Acme profiles have specific exclusions.
  • Designation: Unified 21E24UN threading insert for standardized performance across common applications.

Designed for reliability in job shops and production environments, this insert reduces tool changes and inventory complexity while delivering consistent thread quality. The TiAlN coating helps sustain performance in higher-temperature cuts, and the double-edged design means fewer insert replacements during a run. Whether you’re tackling internal bores or external threads, this unified solution covers a broad range of profiles with solid, repeatable results.

Application Threading
Thread Form UN
Internal or External External
Insert Size 21
Pitch 24

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.

★★★★★
Nice experience staff are very helpful and interested...
Staff are very helpful and interested in providing a good service making us the customer feel valued.
Bill
★★★★★
first place we look
honest about stock and prices are competitive.
Phil
★★★★★
Polite and helpful
Staff are very helpful and polite.Goods that were in stock were dispatched same day and back orders were quick in coming through .
Graham
★★★★★
Buying experience
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.
Jeremy

Full Range: Carmex Carbide Threading Inserts - Unified - TiAlN Coated

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You are viewing 21E24UN. Click any other SKU to view its full details.

Product SKUInsert SizePitchPriceStock Order
12I16UN 1216£26.50 In Stock
12I18UN 1218£26.50 5 days
12I20UN 1220£26.50 In Stock
12I24UN 1224£26.50 5 days
12I28UN 1228£26.50 In Stock
12I32UN 1232£26.50 In Stock
14E10UN 1410£32.37 5 days
14E11UN 1411£32.37 5 days
14E12UN 1412£26.50 In Stock
14E14UN 1414£26.50 In Stock
14E16UN 1416£26.50 In Stock
14E18UN 1418£26.50 5 days
14E20UN 1420£26.50 In Stock
14E24UN 1424£26.50 In Stock
14E28UN 1428£26.50 In Stock
14E32UN 1432£26.50 5 days
14I10UN 1410£26.50 In Stock
14I11UN 1411£26.50 In Stock
14I12UN 1412£26.50 In Stock
14I14UN 1414£26.50 5 days
14I16UN 1416£26.50 In Stock
14I18UN 1418£26.50 In Stock
14I20UN 1420£26.50 In Stock
14I24UN 1424£26.50 In Stock
14I27UN 1427£26.50 In Stock
14I28UN 1428£26.50 In Stock
14I32UN 1432£26.50 In Stock
14I9UN 149£26.50 In Stock
21E10UN 2110£35.22 5 days
21E11UN 2111£43.03 5 days
21E12UN 2112£35.22 5 days
21E14UN 2114£35.22 5 days
21E16UN 2116£35.22 In Stock
21E18UN 2118£35.22 In Stock
21E20UN 2120£35.22 In Stock
21E24UN Viewing2124£35.22 In Stock
21I10UN 2110£35.22 In Stock
21I12UN 2112£35.22 5 days
21I14UN 2114£35.22 In Stock
21I16UN 2116£35.22 In Stock
21I18UN 2118£35.22 In Stock
21I20UN 2120£35.22 In Stock
21I24UN 2124£35.22 In Stock
21I7UN 217£35.22 In Stock
21I8UN 218£35.22 In Stock
30E10UN 3010£48.30 5 days
30E12UN 3012£48.30 5 days
30E14UN 3014£48.30 5 days
30E16UN 3016£48.30 5 days
30E18UN 3018£48.30 5 days
30E20UN 3020£48.30 5 days
30E6UN 306£48.30 5 days
30E8UN 308£48.30 5 days
30I10UN 3010£48.30 5 days
30I12UN 3012£48.30 In Stock
30I14UN 3014£48.30 5 days
30I16UN 3016£48.30 5 days
30I18UN 3018£48.30 In Stock
30I20UN 3020£48.30 5 days
30I5UN 305£48.30 In Stock
30I6UN 306£48.30 5 days
30I8UN 308£48.30 5 days
40E10UN 4010£83.54 5 days
40E12UN 4012£83.54 5 days
40E14UN 4014£83.54 5 days
40E16UN 4016£83.54 5 days
40E6UN 406£83.54 5 days
40E8UN 408£83.54 5 days
40I10UN 4010£83.54 5 days
40I12UN 4012£83.54 5 days
40I14UN 4014£83.54 5 days
40I16UN 4016£83.54 5 days
40I4.5UN 404.5£83.54 5 days
40I4UN 404£83.54 5 days
40I6UN 406£83.54 5 days
40I8UN 408£83.54 5 days

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