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Carmex Thread Mills Solid Carbide - Internal Thread - UN (UNC UNF UNEF UNS) - 1/4 x 20 - MT7
| Thread Form | UN (UNC UNF UNEF UNS) |
| Size | 1/4 |
| Pitch | 20 |
| Diameter (D) | 4.5 |
| Flute Length (l) | 12.1 |
| Shank Diameter (d) | 6 |
Learn more about Klarna
Carmex MT line solid carbide internal thread mills deliver precise, cost-efficient threading for UN family threads. Designed for machining professionals, these tools make reliable internal threads in metal parts with consistent results.
- Thread forms supported: Internal threads in UN family formats (UN, UNC, UNF, UNEF, UNS)
- Size: 1/4"-20 thread size for common UN threading applications
- Shank: MT7 Morse Taper shank for secure toolholding and broad machine compatibility
- Material: Solid carbide construction for rigidity, wear resistance, and long tool life
- Flute count: 3–5 flutes to optimize cutting action, chip evacuation, and finish
- Cutting geometry: Geometry optimized for clean, accurate internal thread generation with minimal chatter
Use cases span precision assemblies in automotive, aerospace, and general mechanical components where reliable UN-threaded connections are essential. The 3–5 flute design supports higher feed rates and efficient material removal, helping reduce cycle times without sacrificing thread accuracy. Ideal for both prototyping and production environments where consistency and durability matter most.
| Thread Form | UN (UNC UNF UNEF UNS) |
| Size | 1/4 |
| Pitch | 20 |
| Diameter (D) | 4.5 |
| Flute Length (l) | 12.1 |
| Shank Diameter (d) | 6 |
| No of Flutes | 3 |
| Overall Length (L) | 58 |
| Thread Mill Style | Standard |
| Internal or External | Internal |
| Coating | MT7 |
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 Solid Carbide Thread Mills - UN (UNC UNF UNEF) - For Internal Thread (MT)
View full collection →You are viewing MT06045C1220UNMT7. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Flute Length | Reach | Overall Length | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| MT06025C640UNMT7 | No.5 | 40 | 6 | 6 | 58 | £86.80 | 5 days | |
| MT06032C632UNMT7 | No. 8 No. 10 No. 12 | 32 | 6.8 | 6.8 | 58 | £86.80 | In Stock | |
| MT06045C1220UNMT7 Viewing | 1/4 | 20 | 12.1 | 12.1 | 58 | £86.80 | 5 days | |
| MT0604C1128UNMT7 | 1/4 | 28 | 11.3 | 11.3 | 58 | £86.80 | 5 days | |
| MT06052C1528UNMT7 | 1/4 | 28 | 15 | 15 | 58 | £86.80 | In Stock | |
| MT0605C1418UNMT7 | 5/16 | 18 | 14.8 | 14.8 | 58 | £86.80 | 5 days | |
| MT0605C1424UNMT7 | 5/16 | 24 | 14.3 | 14.3 | 58 | £86.80 | 5 days | |
| MT0606C1428UNMT7 | 7/16 1/2 | 28 | 14.1 | 14.1 | 58 | £86.80 | 5 days | |
| MT0606C1616UNMT7 | 3/8 | 16 | 16.7 | 16.7 | 58 | £86.80 | 5 days | |
| MT0606C2018UNMT7 | 5/16 | 18 | 20.5 | 20.5 | 58 | £104.16 | 5 days | |
| MT08074C2416UNMT7 | 3/8 | 16 | 24.6 | 24.6 | 64 | £115.62 | In Stock | |
| MT0807C2014UNMT7 | 7/16 | 14 | 20.9 | 20.9 | 64 | £115.62 | 5 days | |
| MT0807C2120UNMT7 | 7/16 1/2 | 20 | 21 | 21 | 64 | £115.62 | In Stock | |
| MT0807C2124UNMT7 | 3/8 | 24 | 24 | 24 | 64 | £115.62 | In Stock | |
| MT0808C2213UNMT7 | 1/2 | 13 | 22.5 | 22.5 | 64 | £115.62 | 5 days | |
| MT10085C2814UNMT7 | 7/16 | 14 | 28.1 | 28.1 | 73 | £133.36 | 5 days | |
| MT10098D3213UNMT7 | 1/2 | 13 | 32.2 | 32.2 | 73 | £133.36 | In Stock | |
| MT1010C2612UNMT7 | 9/16 | 12 | 26.5 | 26.5 | 73 | £133.36 | 5 days | |
| MT1010C2811UNMT7 | 5/8 | 11 | 28.9 | 28.9 | 73 | £133.36 | 5 days | |
| MT1010D2618UNMT7 | 9/16 5/8 - 1 1/8 1 5/8 | 18 | 26.1 | 26.1 | 73 | £133.36 | In Stock | |
| MT12116D3712UNMT7 | 9/16 | 12 | 37 | 37 | 84 | £166.90 | 5 days | |
| MT1212C3410UNMT7 | 3/4 | 10 | 34.3 | 34.3 | 84 | £166.90 | 5 days | |
| MT1212D3116UNMT7 | 3/4 | 16 | 31 | 31 | 84 | £166.90 | In Stock | |
| MT1212D3811UNMT7 | 5/8 | 11 | 38.1 | 38.1 | 84 | £166.90 | 5 days | |
| MT1212E2720UNMT7 | 3/4 - 1 | 20 | 27.3 | 27.3 | 84 | £166.90 | In Stock | |
| MT16147E4910UNMT7 | 3/4 | 10 | 49.5 | 49.5 | 105 | £196.90 | 5 days | |
| MT1615C389UNMT7 | 7/8 | 9 | 38.1 | 38.1 | 105 | £196.90 | In Stock | |
| MT1615E3714UNMT7 | 7/8 | 14 | 37.2 | 37.2 | 105 | £196.90 | 5 days | |
| MT1616C428UNMT7 | 1 | 8 | 42.9 | 42.9 | 105 | £196.90 | 5 days | |
| MT1616E4112UNMT7 | 1 - 1 1/2 | 12 | 41.3 | 41.3 | 105 | £196.90 | 5 days | |
| MT2020D457UNMT7 | 1 1/8 - 1 1/4 | 7 | 45.3 | 45.3 | 105 | £237.79 | 5 days |
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