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Carmex Carbide Threading Insert - UNJ - TiAlN Coated - 21I18UNJ
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | Internal |
| Insert Size | 21 |
| Pitch | 18 |
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The Carmex Carbide Threading Insert - UNJ - TiAlN Coated - 21I18UNJ is a versatile, high-precision threading solution built for machinists who work with UNJ and other common thread profiles. Crafted from carbide and finished with a TiAlN coating, it delivers reliable performance across challenging cutting conditions.
- Material: Carbide insert for exceptional rigidity, wear resistance, and long edge life during high-speed threading.
- Coating: TiAlN coating enhances hardness and heat resistance, helping maintain sharpness and extend tool life.
- Length options: Five lengths available, ranging from 12 mm to 40 mm, to suit different thread profiles and pitch requirements.
- Pitch range: Depending on length, capable of handling pitches from 0.5 mm / 32 TPI up to 6.0 mm / 4 TPI for broad threading versatility.
- Double-sided design: Most inserts feature two cutting edges to maximize usable life (excluding BSPT/NPT/NPTF/American Buttress/API RD profiles).
- Internal/External threading versatility: For many thread profiles, a single insert can machine both internal and external threads, reducing tool changes (with exceptions for ISO / UN / NPSM / UNJ / Acme).
- UNJ-ready: Specifically suited for UNJ thread forms, aligned with the 21I18UNJ designation for precise UNJ applications.
Designed to streamline threading work, this insert helps shops reduce downtime and tooling costs. The TiAlN-coated carbide body maintains edge life under demanding passes, while the range of available lengths and broad profile coverage lets you tackle a wide variety of threading tasks with a single insert family. Whether you’re producing fine pitches or coarser threads, you can expect consistent performance, clean finishes, and reliable repeatability across multiple jobs.
| Application | Threading |
| Thread Form | UNJ |
| Internal or External | Internal |
| Insert Size | 21 |
| Pitch | 18 |
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 - UNJ - TiAlN Coated
View full collection →You are viewing 21I18UNJ. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| 14I24UNJ | 14 | 24 | £22.91 | 5 days | |
| 14E24UNJ | 14 | 24 | £22.91 | 5 days | |
| 14I20UNJ | 14 | 20 | £22.91 | 5 days | |
| 14E20UNJ | 14 | 20 | £22.91 | 5 days | |
| 14I18UNJ | 14 | 18 | £29.81 | In Stock | |
| 14E18UNJ | 14 | 18 | £22.91 | 5 days | |
| 14I16UNJ | 14 | 16 | £22.91 | 5 days | |
| 14E16UNJ | 14 | 16 | £22.91 | 5 days | |
| 14I14UNJ | 14 | 14 | £22.91 | 5 days | |
| 14E14UNJ | 14 | 14 | £22.91 | 5 days | |
| 14I12UNJ | 14 | 12 | £22.91 | 5 days | |
| 14E12UNJ | 14 | 12 | £22.91 | 5 days | |
| 21I24UNJ | 21 | 24 | £30.44 | 5 days | |
| 21E24UNJ | 21 | 24 | £30.44 | 5 days | |
| 21I20UNJ | 21 | 20 | £30.44 | 5 days | |
| 21E20UNJ | 21 | 20 | £30.44 | 5 days | |
| 21I18UNJ Viewing | 21 | 18 | £30.44 | 5 days | |
| 21E18UNJ | 21 | 18 | £30.44 | 5 days | |
| 21I16UNJ | 21 | 16 | £30.44 | 5 days | |
| 21E16UNJ | 21 | 16 | £30.44 | 5 days | |
| 21I14UNJ | 21 | 14 | £30.44 | 5 days | |
| 21E14UNJ | 21 | 14 | £30.44 | 5 days | |
| 21I12UNJ | 21 | 12 | £39.62 | In Stock | |
| 21E12UNJ | 21 | 12 | £30.44 | 5 days |
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