Table Saw Dado Blade: What It Is and Can Your Saw Use One?

On this page (11 sections)

1. What a dado blade is
2. What a dado set cuts
3. Can your saw use a dado blade?
4. Check the arbor size and the blade diameter
5. Groove widths and the shims
6. Dado safety comes from the manual
7. Dado set sizes and what each one needs
8. When a regular blade is enough
9. Blade changes for a dado set
10. Sleds and dado cuts
11. Read the manual before you use a dado set

A table saw dado blade is a stack of saw blades and chippers that cuts a wide, flat-bottomed groove in one pass. Not every saw can use one, so check your saw's manual for the blade diameter, the arbor size and any dado limits before you buy a set.

This guide explains what a dado set does, what to check on your saw, and why the manual comes first. It doesn't say that any particular saw can run one.

What a dado blade is

A dado set has two outside blades, a set of inside chippers and a stack of shims. The outside blades cut the edges of the groove, and the chippers clear the wood between them.

The shims let you change the groove width in small steps. The width depends on how many pieces you stack, so the set's instructions decide the exact build.

What a dado set cuts

A dado set cuts a groove that's wide and flat at the bottom. Shelf supports, drawer parts and joinery often need that shape.

Grooves can run across the grain or along it, depending on the joint. The set cuts the groove in one pass when it's built and set up correctly, which is why it's used for shelving and cabinet parts.

Can your saw use a dado blade?

Not every saw can. Some portable saws aren't designed for dado work, and the manual says whether the saw allows a dado set and at what blade size.

All three sets here are 8-inch sets. Check the diameter your saw's manual allows before you buy, and don't assume a set fits because the saw takes a regular 10-inch blade.

Check the arbor size and the blade diameter

The arbor is the shaft the blade mounts on, and its size has to match the set's bore. Two of these sets list a 5/8-inch arbor, so check your saw's arbor size first.

The manual also shows how the set mounts, which washers go with it and the nut order. Follow those steps before you run the saw.

Groove widths and the shims

The width of the groove is set by the number of chippers and shims in the stack. Add or remove shims until the groove matches the piece it has to fit.

Test the setup on scrap wood before you cut the real stock. Measure the groove with a rule or calipers, and adjust the stack until it matches your part.

Dado safety comes from the manual

Dado work often means changing the guard, riving knife or throat plate setup. Check the manual for the parts you must remove or swap, and don't run the saw without a part unless the manual allows it for that cut.

Set the stack with the saw unplugged, and check every chipper and shim before you turn the saw on. Wear eye and ear protection, and keep your hands out of the blade path.

Dado set sizes and what each one needs

The three sets here are all 8-inch sets, but they differ in parts and groove range. The Freud has two blades, three chippers and a shim set, the Diablo has 12 teeth with shims for fine adjustment, and the Mibro has 14 pieces in a case.

Each set needs a blade diameter and arbor match. Check the manual for the diameter it allows before you buy, since a set that's too large won't fit the saw.

Table saw dado blade setup checks

Check the set's parts against the packing list before you start. Confirm the arbor size, the diameter and the shim count for the groove you need.

Test the setup on scrap before you cut the real stock, and recheck the stack after each adjustment. Keep the chippers and shims in their case so none are lost.

When a regular blade is enough

If the groove doesn't need a flat bottom or a set width, a regular blade may be the simpler choice. Check the manual for the cuts it allows before you decide.

Our best table saw blades roundup compares five regular 10-inch blades for rips and crosscuts.

Blade changes for a dado set

A dado set needs a careful blade change because the stack has more parts than a single blade. Our how to change a table saw blade guide walks through the steps, and the manual sets the rest.

The blade's rotation arrow matters on every blade in the stack, so check the direction before you tighten. Our table saw blade direction guide explains the arrow check.

Sleds and dado cuts

A sled holds stock for crosscuts, which is a different job from a dado cut. Our table saw sled guide explains when a sled helps.

For the saw itself, our portable table saw guide covers the saw types, and it helps you check what your saw can take.

Read the manual before you use a dado set

A dado set is a specialist accessory. The manual decides whether your saw can use one, and it sets the blade size, the arbor, the washers and the guard setup.

Check each step against your saw's manual, and stop if a step doesn't match. Wear eye and ear protection, and keep your hands out of the blade path.

Frequently asked questions

What is a dado blade for a table saw?

A dado blade is a stacked set of outside blades, inside chippers and shims that together cut a wide, flat-bottomed groove in one pass. That makes it useful for shelves and joinery, and the set must be fitted and set up as the manual describes.

Can any table saw use a dado blade?

No. Check your saw's manual for the blade diameter, the arbor size and whether it allows a dado set at all, since some saws aren't designed for dado work.

What size dado set do I need?

The sets here are 8-inch sets, so check the diameter your saw's manual allows before you buy. Groove widths in these sets run from 1/4 inch to 7/8 inch, depending on the set and the shims you use.

Do I need to change the guard to use a dado set?

Dado work often means changing the guard and riving knife setup. Check the manual for the parts you must remove or swap, and don't run the saw without a part unless the manual allows it for that cut.