Please log in here to access all benefits, including promotional discounts and faster checkouts.

Carmex Vertical Milling CMT Three Flute Insert - Threading - C18I20UNMT7
| Application | Threading |
| Thread Form | UN |
| Internal or External | Internal |
| Insert Diameter | 17.8 |
Learn more about Klarna
Compatible holders
The ones our customers buy most.Description
The Carmex Vertical Milling CMT Three Flute Insert - Threading (C18I20UNMT7) is a versatile vertical milling insert designed for threading, grooves, and chamfers. When paired with Carmex vertical milling indexable inserts and tool holders, it handles a wide range of precision milling tasks with reliable, repeatable results.
Its ground profile delivers high precision and excellent performance, even under demanding cutting conditions. This design supports high machining parameters while maintaining a high-quality surface finish, and the solid, accurate clamping method enables full repeatability. The same insert works for right-hand or left-hand threads, simplifying setup and inventory. Toolholders come with a Weldon shank and coolant bore, and chamfer inserts are available to complete finishing tasks.
- Precision-ground profile for consistent threading: Delivers accurate thread geometry and reliable surface quality across production runs.
- High-parameter performance with superior surface finish: Optimized for aggressive cutting parameters while preserving finish quality and part accuracy.
- Universal threading with reliable clamping: One insert works for both right- and left-hand threads, with solid clamping; toolholders include Weldon shank and coolant bore, and chamfer inserts are available for finishing tasks.
This threading-focused insert provides a dependable, efficient solution for machining shops aiming to improve throughput, reduce setup time, and achieve consistent, high-quality threaded features on a variety of materials.
Part Numbers
- Protool Part Number
- C18I20UNMT7
- Brand
- Carmex
- Category
- Thread Mill
Delivery
Free UK mainland delivery on orders over £50 ex VAT. In-stock items ordered before 4:30pm are dispatched the same working day. Full delivery information.
Returns
14-day returns on unused stock items in original packaging. Special-order and bespoke tooling is non-returnable. Read our returns policy.
Technical Support
Over 30 years of machining experience behind the counter. Call 01732 887334, Mon–Thurs 8:30–17:30, Fri 8:30–16:30.
Trade Accounts
Credit accounts, contract pricing and scheduled call-off orders available for trade customers. Apply for an account.
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 Vertical Milling CMT Multi Flute Inserts - Threading - UN
View full collection →You are viewing C18I20UNMT7. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| C10I13UNMT7 | 10 | 13 | £33.36 | In Stock | |
| C25I8UNMT7 | 25 | 8 | £47.16 | In Stock | |
| C18I12UNMT7 | 17.8 | 12 | £41.92 | 5 days | |
| C25I4UNMT7 | 25 | 4 | £47.16 | In Stock | |
| C18I8UNMT7 | 17.8 | 8 | £41.92 | In Stock | |
| C18I32UNMT7 | 17.8 | 32 | £45.76 | In Stock | |
| C18I20UNMT7 Viewing | 17.8 | 20 | £41.92 | In Stock | |
| C18I16UNMT7 | 17.8 | 16 | £41.92 | 5 days | |
| C18I14UNMT7 | 17.8 | 14 | £41.92 | 5 days | |
| C12I32UNMT7 | 12 | 32 | £37.36 | In Stock | |
| C12I24UNMT7 | 12 | 24 | £33.76 | 5 days | |
| C12I20UNMT7 | 12 | 20 | £33.76 | In Stock | |
| C12I18UNMT7 | 12 | 18 | £33.76 | 5 days | |
| C12I11UNMT7 | 12 | 11 | £33.76 | In Stock | |
| C12I10UNMT7 | 12 | 10 | £33.76 | In Stock | |
| C25I7UNMT7 | 25 | 7 | £47.16 | 5 days | |
| C25I6UNMT7 | 25 | 6 | £47.16 | 5 days | |
| C25I5UNMT7 | 25 | 5 | £47.16 | 5 days | |
| C18I9UNMT7 | 17.8 | 9 | £41.92 | 5 days | |
| C18I28UNMT7 | 17.8 | 28 | £41.92 | In Stock | |
| C18I24UNMT7 | 17.8 | 24 | £41.92 | In Stock | |
| C18I18UNMT7 | 17.8 | 18 | £41.92 | In Stock | |
| C18I11UNMT7 | 17.8 | 11 | £41.92 | In Stock | |
| C12I28UNMT7 | 12 | 28 | £33.76 | In Stock | |
| C12I16UNMT7 | 12 | 16 | £33.76 | 5 days | |
| C12I12UNMT7 | 12.4 | 12 | £33.76 | In Stock | |
| C10I20UNMT7 | 10 | 20 | £33.36 | 5 days | |
| C10I18UNMT7 | 10 | 18 | £33.36 | In Stock | |
| C10I12UNMT7 | 10 | 12 | £33.36 | In Stock |
No products match your filters.






