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Carmex Thread Mills Solid Carbide - Fast Type - For Hard Materials - UN (UNC UNF UNEF UNS) - No. 4 x 40 - MT3
| Thread Form | UN (UNC UNF UNEF UNS) |
| Size | No. 4 |
| Pitch | 40 |
| Diameter (D) | 2.1 |
| Flute Length (l) | 1.91 |
| Shank Diameter (d) | 6 |
Learn more about Klarna
Carmex FSH solid carbide thread mills are engineered for hard materials and precision UNC/UNF/UNEF/UNS thread production. This No. 4 x 40 tool with an MT3 shank delivers dependable performance in demanding applications, from aerospace components to precision dies.
- Thread format and size: Designed for UNC, UNF, UNEF, and UNS threads; No. 4 x 40 size for reliable fit and finish.
- MT3 shank: Compatible with standard MT3 collets for secure, repeatable mounting.
- Ultra-fine grade with PVD coating: MT3-grade carbide with a multi-layer PVD coating enhances heat resistance and wear life in harsh materials.
- High-flute-count geometry: Up to 7 flutes on selected models improves rigidity, chip evacuation, and surface finish in tough workpieces.
- Fast Type design: Optimized geometry for rapid thread milling, reducing cycle times without sacrificing accuracy.
- Hard material capability: Machining capability up to 65 HRC, making it suitable for stainless steels, nickel-based superalloys, and other hard materials.
The combination of a stable cutting edge, multi-layer coating, and a versatile threading size makes this Carmex thread mill a reliable choice for high-precision internal threads. Expect clean, consistent thread profiles, longer tool life, and reduced burr formation across repeated runs. For best results, pair with appropriate coolant, use conservative feeds and speeds, and perform finish passes to achieve the tight tolerances your parts demand.
| Thread Form | UN (UNC UNF UNEF UNS) |
| Size | No. 4 |
| Pitch | 40 |
| Diameter (D) | 2.1 |
| Flute Length (l) | 1.91 |
| Shank Diameter (d) | 6 |
| No of Flutes | 4 |
| Overall Length (L) | 58 |
| Thread Mill Style | Mini (Fast) |
| Internal or External | Internal |
| Coating | MT3 |
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 Thread Mills - UN - Mini Type For Hard Materials Up To 65HRC (FSH)
View full collection →You are viewing FSH06021D640UNMT3. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Flute Length | Reach | Overall Length | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| FSH06021D640UNMT3 Viewing | No. 4 | 40 | 1.91 | 6.3 | 58 | £83.11 | 5 days | |
| FSH06021D940UNMT3 | No. 4 | 40 | 1.91 | 9.2 | 6 | £114.68 | 5 days | |
| FSH06024D1040UNMT3 | No. 5 No. 6 | 40 | 1.91 | 10.2 | 58 | £83.11 | 5 days | |
| FSH06024D740UNMT3 | Mo. 5 No. 6 | 40 | 1.91 | 7 | 58 | £83.11 | 5 days | |
| FSH06025D1132UNMT3 | No. 6 | 32 | 2.38 | 11.3 | 58 | £83.11 | 5 days | |
| FSH06025D732UNMT3 | No. 6 | 32 | 2.38 | 7.8 | 58 | £83.11 | 5 days | |
| FSH06032D1332UNMT3 | No. 8 | 32 | 2.38 | 13.3 | 58 | £83.11 | 5 days | |
| FSH06032D932UNMT3 | No. 8 | 32 | 2.38 | 9.1 | 58 | £83.11 | 5 days | |
| FSH06038E1032UNMT3 | No. 10 | 32 | 2.38 | 10.5 | 58 | £83.11 | 5 days | |
| FSH06038E1532UNMT3 | No. 10 | 32 | 2.38 | 15.3 | 58 | £83.11 | 5 days | |
| FSH06048E1420UNMT3 | 1/4 | 20 | 3.81 | 14 | 58 | £83.11 | 5 days | |
| FSH06048E2020UNMT3 | 1/4 | 20 | 3.81 | 20.3 | 58 | £83.11 | 5 days | |
| FSH06052F1328UNMT3 | 1/4 | 28 | 2.72 | 13.6 | 58 | £83.11 | 5 days | |
| FSH06052F2028UNMT3 | 1/4 | 28 | 2.72 | 20 | 58 | £114.70 | 5 days | |
| FSH08066F1624UNMT3 | 5/16 3/8 | 24 | 3.18 | 16.9 | 64 | £110.83 | 5 days | |
| FSH08066F2424UNMT3 | 5/16 3/8 | 24 | 3.18 | 24.9 | 64 | £110.83 | 5 days |
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