Please log in here to access all benefits, including promotional discounts and faster checkouts.

Carmex Carbide Tiny Tool - Boring Bar - MTL - K20 Grade - 1mm Minimum Diameter x 4mm Reach x R0.05 (Left Hand)

Carmex Carbide Tiny Tool - Boring Bar - MTL - K20 Grade - 1mm Minimum Diameter x 4mm Reach x R0.05 (Left Hand)

SKU:MTL1R0.05L4K20

The Carmex Carbide Tiny Tool is a micro boring bar crafted from solid carbide (K20 grade). With a 1 mm minimum diameter, 4 mm reach, and a left-hand geometry featuring an R0.05 tip, it’s built for... Read more ↓
M
K
N
S
ApplicationBoring (MTL)
Minimum Diameter1
Reach (L1)4
Radius (R)0.05
View all specifications ↓
Download Cutting Data
£22.40
Prices shown ex. VAT
5 days estimated lead time — subject to availability
Free delivery over £50 ex VAT
Secure checkout
14-day returns
30+ years expertise
Klarna
Pay in 3 interest-free instalments. No extra cost if paid on time. 18+ only.
Learn more about Klarna
Speak to our team
01732 887334
Mon – Thurs 8:30 – 17:30 · Fri 8:30 – 16:30

Description

The Carmex Carbide Tiny Tool is a micro boring bar crafted from solid carbide (K20 grade). With a 1 mm minimum diameter, 4 mm reach, and a left-hand geometry featuring an R0.05 tip, it’s built for clean, accurate internal cuts on small parts. While optimized for boring, it also handles a wide range of general turning tasks, giving you a compact, versatile tool for delicate work and fine tolerances.

This tiny tool is offered in two high-performance grades to match different materials and speeds. BXC is a PVD TiN-coated grade designed for low cutting speeds and broad stainless-steel compatibility (ISO P30-P50 / K25-K40). BMK is a sub-micron grade with advanced PVD triple coating, delivering exceptional heat resistance and smooth cutting for demanding applications (ISO K10-K20). These options let you tailor the tool to the job without switching tools.

  • Dual coating options for versatility: BXC TiN-coated for low-speed cutting and stainless steels, or BMK’s triple-coated sub-micron grade for high-heat performance—so you can tackle a wide range of materials with one tiny tool.
  • Micro-diameter bore bar with long reach: 1 mm minimum diameter and 4 mm reach, plus a precise R0.05 radius for tight internal features and smooth bore finishes in confined spaces.
  • Solid carbide efficiency and heat resistance: K20-grade carbide combined with advanced coatings delivers durable cutting life, stable performance, and reliable results across challenging materials.

This micro boring tool helps you complete precise internal work with fewer tool changes, better surface finishes, and consistent results. Its small footprint fits into tight bores while maintaining rigidity and control, enabling smoother workflows, tighter tolerances, and improved productivity across a variety of materials.

Part Numbers

Protool Part Number
MTL1R0.05L4K20
Brand
Carmex
Category
Tiny Tool Inserts
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.

Ask our technical team about this tool

Not sure if this is the right tool for your job? Ask us about speeds and feeds, material suitability, holders or alternatives — 30+ years of machining experience on the other end.

Prefer to talk? Call 01732 887334 — Mon–Thurs 8:30–17:30, Fri 8:30–16:30.

Complete Your Project

Tooling and consumables that work with this product.
All 12 →