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Carmex Vertical Milling CMT Three Flute Insert - Threading - C18I4TRMT7
| Application | Threading |
| Thread Form | Trapez |
| Internal or External | Internal |
| Insert Diameter | 17.8 |
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The ones our customers buy most.Description
The Carmex Vertical Milling CMT Three-Flute Insert for Threading is an indexable cutting insert designed for vertical milling, enabling threads, grooves, and chamfers with precision.
Built for engineers, buyers, tradespeople, and hobbyists, this solution emphasizes high-precision threading and reliable performance. Ground-profile inserts in the CMT Vertical Mill-Thread line deliver excellent results at higher machining parameters and a smooth surface finish, while a solid, accurate clamping method ensures full repeatability. The same insert handles both right-hand and left-hand threads, and the toolholders include a weldon shank and coolant bore; chamfer inserts are also available.
- Ground-profile inserts for high precision: Precise, ground profiles ensure consistent form and tight tolerances for threading and grooves, delivering reliable results even at higher speeds and loads.
- Solid, repeatable clamping: The robust clamping method provides accurate repeatability across cycles, helping reduce rework and keep production moving smoothly.
- RH/LH threading compatibility with ready-to-use tooling: The insert works for both right- and left-hand threads, and toolholders include weldon shank and coolant bore, with chamfer inserts available to simplify setup and workflow.
By combining ground-profile precision, repeatable clamping, and universal threading capability, this insert helps you achieve consistent thread quality and reliable performance in vertical milling applications. The weldon-shank toolholders with coolant bore streamline integration, and chamfer inserts extend your capability without adding extra tooling.
Part Numbers
- Protool Part Number
- C18I4TRMT7
- 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 Single Flute Inserts - Trapez
View full collection →You are viewing C18I4TRMT7. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| C10I2TRMT7 | 10 | 2 | £33.36 | In Stock | |
| C12I2TRMT7 | 12 | 2 | £28.04 | 5 days | |
| C18I3TRMT7 | 17.8 | 3 | £41.92 | In Stock | |
| C18I4TRMT7 Viewing | 17.8 | 4 | £41.92 | 5 days | |
| C18I5TRMT7 | 17.8 | 5 | £41.92 | 5 days | |
| C25I6TRMT7 | 25 | 6 | £47.16 | 5 days |
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