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Carmex Carbide Tiny Tool - Thread Relief, Chamfering & Grooving - MDR - K20 Grade - 4.1mm Minimum Diameter x 0.8mm Reach x R0.5
| Application | Thread Relief Chamfering & Grooving (MDR) |
| Groove Depth (L1) | 18 |
| Minimum Diameter | 4.1 |
| Reach (H) | 0.8 |
| Radius (R) | 0.5 |
| L | 51 |
Learn more about Klarna
The Carmex Carbide Tiny Tools - Small Thread Relief, Chamfering & Grooving Tool (MDR) is a compact, high-precision cutting tool built for tiny features. Designed for engineers, machinists, hobbyists, and technicians working in tight spaces, it delivers accurate thread relief, clean chamfers, and precise grooves on small parts.
Crafted from premium K20-grade carbide, this MDR tool combines standout durability with dependable performance. Its small 4.1 mm minimum diameter, 0.8 mm reach, and R0.5 corner radius make it ideal for delicate operations where precision and surface finish matter.
- Small-diameter precision for tight spots: Perfect for tiny threads, chamfers, and grooves on miniature parts. The compact tip maintains accurate cutting geometry in confined spaces, delivering clean starts and reduced burrs on every pass.
- Premium K20 carbide for long life: Made from high-grade carbide that resists wear and maintains a sharp edge through demanding jobs, minimizing tool changes and delivering consistent results across multiple parts.
- Compact reach and corner geometry: With a 0.8 mm reach and an R0.5 radius, this tool handles thread relief, chamfering, and grooving with controlled transitions and smooth surface finishes on small features.
This tiny tool helps you streamline your workflow by allowing precise operations in tight areas without sacrificing edge quality or performance. Its durable carbide and compact design reduce downtime from tool changes, improve part-to-part consistency, and support reliable results in small-diameter components, making it a dependable choice for production and hobby projects alike.
| Application | Thread Relief Chamfering & Grooving (MDR) |
| Groove Depth (L1) | 18 |
| Minimum Diameter | 4.1 |
| Reach (H) | 0.8 |
| Radius (R) | 0.5 |
| L | 51 |
| B | 1.5 |
| F | 1.8 |
| D | 4.0 |
| Grade | K20 |
| Holder | SIM****H4 |
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 Tiny Tools - Thread Relief, Chamfering & Grooving - Grade K20 (MDR)
View full collection →You are viewing MDR4R0.5L18K20. Click any other SKU to view its full details.
| Product SKU | Groove Depth | Minimum Diameter | Reach | Radius | Grade | Holder | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|---|
| MDR6R0.5L27K20 | 27 | 6.1 | 1.4 | 0.5 | K20 | SIM****H6 | £30.73 | 5 days | |
| MDR5R0.5L24K20 | 24 | 5.1 | 1.2 | 0.5 | K20 | SIM****H5 | £26.23 | 5 days | |
| MDR4R0.5L18K20 Viewing | 18 | 4.1 | 0.8 | 0.5 | K20 | SIM****H4 | £22.48 | 5 days | |
| MDL4R0.5L18K20 | 18 | 4.1 | 0.8 | 0.5 | K20 | SIM****H4 | £22.48 | 5 days | |
| MDL5R0.5L24K20 | 24 | 5.1 | 1.2 | 0.5 | K20 | SIM****H5 | £26.23 | 5 days | |
| MDL6R0.5L27K20 | 27 | 6.1 | 1.4 | 0.5 | K20 | SIM****H6 | £30.73 | 5 days |
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