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Carmex Vertical Milling CMT Three Flute Insert - Threading - C251/4RDMT7

SKU:C251/4RDMT7

The Carmex Vertical Milling CMT Three Flute Insert – Threading (C251/4RDMT7) is a versatile, indexable insert designed for vertical milling applications. It excels at producing threads, grooves, ... Read more ↓
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ApplicationThreading
Thread FormRound- DIN 407
Internal or ExternalInternal
Insert Diameter25
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£47.10
Prices shown ex. VAT
5 days estimated lead time — subject to availability
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Free delivery over £50 ex VAT
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14-day returns
30+ years expertise
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01732 887334
Mon – Thurs 8:30 – 17:30 · Fri 8:30 – 16:30

Description

The Carmex Vertical Milling CMT Three Flute Insert – Threading (C251/4RDMT7) is a versatile, indexable insert designed for vertical milling applications. It excels at producing threads, grooves, chamfers and more with consistent results, making it suitable for engineers, machinists, tradespeople, and hobbyists who value reliable performance.

Built around a ground profile, this CMT threading insert delivers high precision and a smooth surface finish even when you push cutting parameters. Its solid and accurate clamping method ensures full repeatability across multiple parts, so you can count on repeatable results job after job. The same insert supports right-hand or left-hand threading, simplifying stocking and setups, and the toolholders include a weldon shank and coolant bore for practical, integrated use. Chamfer inserts are also available if you need to add finishing features in the same setup.

  • Ground profile for high precision: Delivers tight tolerances and high-quality surfaces during threading and grooves, even at higher cutting parameters.
  • Solid, repeatable clamping: Provides reliable workholding and full repeatability across parts and setups.
  • Versatile threading and accessories: One insert handles both right- and left-hand threads, with weldon shank toolholders and coolant bore, and chamfer inserts available for streamlined setups.

This combination of precision geometry, reliable clamping, and universal threading capability helps you complete threaded, grooved, and chamfered features in fewer setups with consistent quality. By reducing tool changes and enabling standardization across jobs, it speeds up workflows and improves finish quality, giving you predictable results and greater confidence in every part you ship.

Part Numbers

Protool Part Number
C251/4RDMT7
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.

Ask our technical team about this tool

Not sure if this is the right tool for your job? Ask us about speeds and feeds, material suitability, holders or alternatives — 30+ years of machining experience on the other end.

Prefer to talk? Call 01732 887334 — Mon–Thurs 8:30–17:30, Fri 8:30–16:30.

Full Range: Carmex Vertical Milling CMT Single Flute Inserts - Round DIN 405

View full collection →

You are viewing C251/4RDMT7. Click any other SKU to view its full details.

Product SKUInsert SizePitchPriceStock Order
C181/6RDMT7 17.86£42.14 In Stock
C181/8RDMT7 17.88£42.14 In Stock
C251/4RDMT7 Viewing254£47.10 5 days

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