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Carmex Thread Mills Mini Type - Through Coolant - UN (UNC UNF UNEF UNS) - No. 4 x 40 - MT7
| Thread Form | UN (UNC UNF UNEF UNS) |
| Size | No. 4 |
| Pitch | 40 |
| Diameter (D) | 2.1 |
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Description
Carmex’s Thread Mills Mini Type with through coolant is a precision solid carbide cutter designed for small-diameter internal threading in pre-drilled holes. Built for UN-thread forms, it delivers reliable performance in tight spaces with efficient chip evacuation.
- Tool type: Solid carbide thread milling cutter (MTSB) with an internal coolant bore
- Coolant delivery: Through-tool coolant bore provides high-pressure liquid directly to the cutting edge, cooling the tool and aiding chip removal
- Thread forms supported: UNC, UNF, UNEF, and UNS threading standards
- Size and shank: No. 4 cutting diameter, 40 mm length; MT7 shank
- Cutting geometry: Optimized miniature thread-milling geometry for smooth traversal along the threading circle
The through-coolant design reduces heat buildup at the cutting edge, helping extend tool life and maintain consistent thread accuracy throughout the hole. With enhanced chip clearance and cooling, this cutter is well-suited for precise, durable threads in small diameters across demanding materials and applications, from mold making to precision mechanical assemblies.
Part Numbers
- Protool Part Number
- MTSB06021D940UNMT7
- 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 Carbide Thread Mills - UN Mini Type With Internal Coolant Bore (MTSB)
View full collection →You are viewing MTSB06021D940UNMT7. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Flute Length | Reach | Overall Length | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| MTSB06012C480UNMT7 | No. 4 | 80 | 0.95 | 4.9 | 58 | £117.11 | 5 days | |
| MTSB06014C572UNMT7 | No. 1 | 72 | 1.06 | 5.9 | 58 | £117.11 | 5 days | |
| MTSB06016C456UNMT7 | No. 2 No. 3 | 56 | 1.36 | 4.8 | 58 | £117.11 | 5 days | |
| MTSB06016C756UNMT7 | No. 2 No. 3 | 56 | 1.36 | 7 | 58 | £117.11 | 5 days | |
| MTSB06019D548UNMT7 | No. 3 No. 4 | 48 | 1.59 | 5.6 | 58 | £117.11 | 5 days | |
| MTSB06021D1240UNMT7 | No. 4 | 40 | 1.91 | 12 | 58 | £117.11 | 5 days | |
| MTSB06021D640UNMT7 | No. 4 | 40 | 1.91 | 6.3 | 58 | £117.11 | 5 days | |
| MTSB06021D940UNMT7 Viewing | No. 4 | 40 | 1.91 | 9.2 | 58 | £117.11 | In Stock | |
| MTSB06024D740UNMT7 | No. 5 No. 6 | 40 | 1.91 | 7 | 58 | £117.11 | 5 days | |
| MTSB06025D1132UNMT7 | No. 6 | 32 | 2.38 | 11.3 | 58 | £117.11 | 5 days | |
| MTSB06025D732UNMT7 | No. 6 | 32 | 2.38 | 7.8 | 58 | £117.11 | 5 days | |
| MTSB06032D1332UNMT7 | No. 8 | 32 | 2.38 | 13.3 | 58 | £117.11 | 5 days | |
| MTSB06032D932UNMT7 | No. 8 | 32 | 2.38 | 9.1 | 58 | £117.11 | 5 days | |
| MTSB06035D1024UNMT7 | No. 10 No. 12 | 24 | 3.18 | 10.7 | 58 | £117.11 | 5 days | |
| MTSB06035D1524UNMT7 | No. 10 No. 12 | 24 | 3.18 | 15.5 | 58 | £117.11 | 5 days | |
| MTSB06037D1032UNMT7 | No. 10 | 32 | 2.38 | 10.5 | 58 | £117.11 | 5 days | |
| MTSB06037D1532UNMT7 | No. 10 | 32 | 2.38 | 15.3 | 58 | £117.11 | 5 days | |
| MTSB06052D2028UNMT7 | 1/4 | 28 | 2.72 | 20 | 58 | £117.11 | 5 days | |
| MTSB08066D2424UNMT7 | 5/16 3/8 | 24 | 3.18 | 24.9 | 64 | £156.17 | 5 days | |
| MTSB10092E3420UNMT7 | 7/16 1/2 | 20 | 3.81 | 34.6 | 73 | £202.07 | 5 days |
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