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Carmex Carbide Tiny Tool - Boring Bar - MTR - K20 Grade - 3.1mm Minimum Diameter x 15mm Reach x R0.1
| Application | Boring (MTR) |
| Minimum Diameter | 3.1 |
| Reach (L1) | 15 |
| Radius (R) | 0.1 |
| Grade | K20 |
| Holder | SIM****H3 |
Learn more about Klarna
The Carmex Carbide Tiny Tool is a compact, solid carbide boring bar designed for tight-diameter borework and precise turning. With a minimum diameter of 3.1 mm, a 15 mm reach, and a tight R0.1 nose radius, it fits into restricted passages while delivering clean, repeatable cuts. Built on K20 grade solid carbide, this tiny tool is suited for engineers, machinists, hobbyists, and shop-floor operators, delivering dependable performance in boring and general turning tasks.
Two coating variants are offered on this tool line to match material and speed requirements. BXC is a PVD TiN-coated grade optimized for low cutting speeds and performs well with a wide range of stainless steels (ISO P30-P50 / K25-K40). BMK uses a sub-micron grade with advanced PVD triple coating, delivering extremely high heat resistance and smooth cutting for general-purpose use across materials.
- Coating options for optimized material performance: Choose BXC for stainless steels at low speeds or BMK for high-heat, general-purpose cutting, extending tool life and improving surface finish.
- Ultra-compact, rigid geometry for tight bores: 3.1 mm minimum diameter, 15 mm reach, and a 0.1 mm nose radius enable precise, repeatable cuts in restricted spaces with solid carbide rigidity.
- Versatile boring and turning capability: Designed primarily for boring but suitable for general turning, reducing tool changes and increasing workflow flexibility across mixed operations.
This tiny carbide bar combines size, strength, and adaptable coatings to deliver consistent, reliable performance in small-diameter work. It helps you achieve accurate bore quality, smooth finishes, and efficient setups—whether you're machining precision features in stainless steel or tackling a range of materials with a single tool.
| Application | Boring (MTR) |
| Minimum Diameter | 3.1 |
| Reach (L1) | 15 |
| Radius (R) | 0.1 |
| Grade | K20 |
| Holder | SIM****H3 |
| L | 39 |
| F | 1.3 |
| D | 3 |
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.