You are here

How do I make smooth-bottomed dadoes?


How can I cut dadoes with smooth, even bottoms using my tablesaw dado set? My set leaves ridges even though I just had it sharpened.
—Walter McCoy, Salina, Kan.


Unfortunately, Walter, very few stacked dado sets leave a perfectly smooth, flat channel, even when brand new. In most cases, it’s not a big deal because you’ll never see the joint after you’ve assembled the project. But when you need it dead flat, use a dado cleanout bit, shown above, in your handheld router. These bits have a shallow cutter, 18 " to 14 " in thickness, leaving room on the dado’s shoulder for the bearing to register against. If your dado needs to be a specific depth upon completion, be sure to deduct the to-be-routed depth when setting the height of your stacked dado set.

The stacked dado set that cut this channel left ridges in the bottom caused by slight height variances between chippers and blades.

The remove the ridges, set a cleanout bit to shave 1⁄32" or so from the dado bottom. Holding the bearing against the shoulder, rout down and back.

Read more about

Tip of the Day

Put the skewer to glue squeeze-out

Removing excess glue from inside corners can be a challenge. I used to do the job with a putty... read more