Product Description
CMT Hinge Boring Bit 25 x 57.5mm Left-Hand Rotation by CMT is a precision-engineered boring bit designed specifically for drilling flat-bottom hinge cup holes used in European-style concealed hinge installations. Built around a tungsten carbide (HW) cutting head with a super-strength steel body, this 25mm diameter bit delivers clean, accurate bores in cabinet doors, face frames, and panel components. The left-hand (LH) rotation and 10x26mm parallel shank with driving flat make it compatible with boring machines equipped with adaptors or chucks, giving woodworkers and cabinet shop operators a reliable tool for repeatable, high-quality results.
Key Features
- HW (Tungsten Carbide) Cutting Head with Precision Balanced Centre Point - the carbide construction maintains a sharp, accurate cutting edge through extended production runs, reducing downtime and regrind frequency.
- 2 Precision Ground HW Cutting Edges (Z2) - dual carbide cutting edges distribute cutting load evenly, producing smooth, flat-bottom bore walls essential for proper European hinge cup seating.
- 2 Negatively Ground Spurs (V2) - the negative grind geometry scores the wood fiber ahead of the cutters, preventing tear-out at the bore perimeter and delivering clean entry on hardwood, MDF, chipboard, and plywood surfaces.
- PTFE Coating on the Cutter Portion - the orange or black P.T.F.E. surface treatment resists pitch and resin adhesion, keeping the bit running freely and extending service life between cleanings.
- Super-Strength Steel Body - provides rigidity and vibration resistance during boring operations, contributing to dimensional accuracy across repeated hole cycles.
- Parallel Shank with Driving Flat and Length Adjusting Screw - the 10x26mm shank design seats securely in boring machine adaptors or chucks, and the adjusting screw allows precise depth-of-cut setting for consistent hinge cup depth.
- Left-Hand (LH) Rotation - matches the spindle direction of left-hand boring machine spindles, ensuring correct cutting action and chip evacuation without forcing the bit in the wrong direction.
Why This Product
- The flat-bottom bore geometry produced by the negatively ground spurs and precision carbide cutters is the exact geometry required for European concealed hinges - no secondary operations needed to achieve proper hinge cup fit.
- The HW carbide cutting head withstands the demands of high-volume cabinet production on composite panels such as MDF, chipboard, and plywood without rapid edge degradation that would compromise hole quality.
- The P.T.F.E.-coated cutter portion reduces resin and pitch buildup during boring in solid hardwood and softwood, meaning less frequent cleaning and more consistent performance across a production shift.
- The 10x26mm parallel shank with driving flat and length adjusting screw makes this bit a direct fit for boring machines equipped with adaptors or chucks, simplifying tool changeover and depth setup in multi-spindle production environments.
Specifications
- Manufacturer Part Number: 317.250.12
- Brand: CMT Orange Tools
- Diameter: 25mm
- Total Length: 57.5mm
- Shank: 10x26mm
- Rotation: LH (Left-Hand)
- Number of Spurs: 2
- Number of Teeth: 2
- Tooth Geometry: Negatively ground spurs
- Material: HW (Tungsten Carbide)
- Product Type: Hinge Boring Bit
Approved Applications
- Drilling flat-bottom hinge cup holes for European-style concealed hinge installation
- Cabinet door hinge cup boring
- Face frame hinge mounting preparation
- Use on boring machines equipped with adaptors or chucks
- Panel processing in solid hardwood, softwood, chipboard, MDF, and plywood
Frequently Asked Questions
What machines is this hinge boring bit compatible with?
This bit is designed for boring machines equipped with adaptors or chucks. The 10x26mm parallel shank includes a driving flat and a length adjusting screw to ensure secure, accurate seating in those machine configurations.
Why does rotation direction matter, and which direction does this bit rotate?
This bit is a left-hand (LH) rotation tool. Using a bit in the wrong rotation direction for your spindle will cause incorrect cutting action, poor hole quality, and potential tool damage. Always confirm your boring machine spindle rotates left-hand before installing this bit.
What is the purpose of the negatively ground spurs on this bit?
The 2 negatively ground spurs score the wood fiber at the perimeter of the bore before the main cutters remove material. This prevents tear-out and splintering at the hole edge, which is especially important when boring cabinet door panels where a clean, finished appearance is required.
What does the P.T.F.E. coating on the cutter portion do?
The orange or black P.T.F.E. coating applied to the cutter portion resists the adhesion of pitch, resin, and glue. This keeps the cutting surfaces cleaner during use, reduces the friction that can cause burning or discoloration in the bore, and extends the interval between cleanings for more consistent performance over time.
Reviews
FAQs
Standard Shipping is free on most orders over $50 within the contiguous US. If the order is under $50.00, the shipping is $9.99 set fee for shipping within the contiguous US.
Most of our products will ship within 1 to 3 Business Days. Some Special order products will ship within 2 to 5 Business Days. Preorders will be shipped to you on a first come first serve basis as soon as available from the manufacturer. Items that are "Made-to-Order" (Custom order products) will be shipped when fabrication is completed, shipping and delivery times will vary and depend on manufacturing.
Products that are shipped directly from the manufacturer will have processing and fulfilment times subject to manufacturer availability.
Preorders are shipped on a first come first serve basis as soon as available from the manufacturer, the sooner you place your Preorder the sooner your order will ship.
Freight shipping Policy:
Orders/Items too large or heavy may require special handling/Shipping and may require to be sent by truck. Someone must be present to accept truck deliveries. Standard truck delivery is to a dock facility designed to receive freight. You will be notified within 24 hours of ordering to confirm delivery. Lift gates for deliveries are available for an additional fee.
We offer Financing options through Clicklease
Please email your Return request to info@FactoryDirectSupplyOnline.com
Include the order number and the reason for your return.
All returns, regardless of their categorization, must include all original parts, be in their original packaging, and in the condition in which they were received. You may not qualify to receive a refund If the returned item is used, damaged, missing any parts, or is damaged during return shipping.
Checkout our complete Return policy
You can contact us through our contact page! We will be happy to assist you.