The CMT 299.220.00 Reduction Ring from CMT is a precision-machined saw blade arbor adapter designed to reduce a 1-inch (25.4mm) outer diameter down to a 20mm inner bore, allowing circular saw blades with a 1-inch arbor hole to be mounted securely on machines with a 20mm arbor. Whether you are adapting a table saw blade, miter saw blade, or other circular saw blade to a smaller spindle, this reducing bushing delivers a snug, reliable fit that keeps your blade centered and stable during operation.

Key Features

• 1-inch (25.4mm) outer diameter to 20mm inner bore reduction - bridges the gap between blade arbor holes and smaller machine spindles, expanding compatibility across a wide range of circular saw blades and machines
• Maximum thickness of 0.089 inches - a slim profile ensures the ring seats flush within the blade's arbor hole without adding unwanted runout or blade deflection
• Adjustable arbor hole compatibility - provides a flexible solution for fitting blades to different arbor sizes, reducing the need to purchase multiple blade sets for different machines
• Available in multiple saw blade arbor adapter ring sizes - makes it straightforward to find the exact reduction pairing you need for stationary table saws, miter saws, and other equipment
• Machined to precise tolerances - a secure, wobble-free fit helps maintain accurate cuts and protects both the blade and the machine spindle

Why This Product

• Solves the common mismatch between a 1-inch blade arbor hole and a 20mm machine spindle, letting you use a wider selection of saw blades without replacing equipment
• The slim 0.089-inch maximum thickness keeps the blade seating geometry intact, so your cuts remain precise and square after the adapter is installed
• Designed specifically as a saw blade reducing bushing, this ring is engineered for the high-speed, high-vibration environment of circular saw applications rather than being a generic spacer
• Part of a range of arbor adapter ring sizes from CMT, making it easy to build a set of reduction rings that cover multiple machine and blade combinations in your shop

Specifications

• Manufacturer Part Number: 299.220.00
• Brand: CMT Orange Tools
• Outer Diameter: 1 inch (25.4mm)
• Small Diameter: 20mm
• Bore Diameter: 20mm
• Maximum Thickness: 0.089 inches

Approved Applications

• Reducing the arbor size of circular saw blades to fit a 20mm machine spindle
• Adapting table saw blades from a 1-inch arbor hole to a 20mm arbor
• Adapting miter saw blades from a 1-inch arbor hole to a 20mm arbor
• Providing an adjustable arbor hole fit for a variety of saw blade and machine pairings

Frequently Asked Questions

What does the CMT 299.220.00 reduction ring actually do?

This ring is a saw blade reducing bushing that fits inside a saw blade's 1-inch (25.4mm) arbor hole and reduces it down to a 20mm bore. This lets you mount a blade with a 1-inch arbor hole onto a machine that has a 20mm spindle, without needing a different blade or a different machine.

Will this reduction ring fit my table saw and my miter saw?

Yes - the bushing is designed for use with circular saw blades in general, including table saw blades and miter saw blades. As long as your blade has a 1-inch arbor hole and your machine has a 20mm arbor, this ring is the correct adapter.

What is the maximum thickness of this reduction ring, and does it affect blade installation?

The maximum thickness is 0.089 inches. This slim dimension is intentional - it allows the ring to seat fully within the blade's arbor hole so the blade sits correctly against the machine flange, maintaining proper geometry and minimizing runout.

Are other sizes of CMT arbor adapter reduction rings available?

Yes - the CMT 299 series includes reduction rings available in different saw blade arbor adapter ring sizes. If you need a different outer diameter or inner bore combination, additional options are available within the same product family.