With a good stacked-dado set costing from $80 to $270, you may be thinking twice about pulling the trigger on that purchase. To help justify spending so much, consider the fast, effective joinery you can crank out using only a tablesaw and dado set.
Joint in middle of board

1. Dado or groove joint

You cut these narrow channels in different directions: Dadoes go across the grain; grooves run with the grain. Not only do they add significant mechanical strength to butt joints, but also the "walls" of the dado or groove provide additional glue surface area for superior bonding.

Front view of board going thru dado blades

2. Rabbet joint

A partial groove or dado cut along the end or edge of a workpiece, a rabbet allows you to attach a cabinet top, bottom, or back flush with the adjacent workpiece.

Top joint over laps bottom

Here's how: Install your full dado set and clamp an auxiliary rip fence to your tablesaw's fence. Bury part of the blade in the fence by lowering the blade below the table; moving the auxiliary fence over the blade; and, with the saw turned on, slowly raising the blade into the auxiliary fence. You can now fine-tune the width of your rabbet by adjusting your rip fence instead of the width of your dado set.

Board on side of Auxiliary fence

3. Tongue-and-groove joint

In this joint, the center tongue of one board (about 13 the thickness of the board) fits into the groove of the adjoining board. This provides a strong mechanical bond while aligning your boards—ideal for edge-to-edge joints.

Joint more like a puzzle, in the middle
Note: When adjusting the fence, remember that adjustment doubles because you recut both sides of the tongue.

Here's how: To perfectly center the groove, set the rip fence to locate the groove approximately in the center of the board; cut the groove. Then, rotate the workpiece 180° and make another pass with the workpiece's opposite face against the fence. For the tongue, use an auxiliary rip fence and cut a rabbet along both edges of the board, leaving the tongue a little oversize. Test the fit, adjust the fence, and recut both rabbets.

2 photos, tongue joint

4. Half-lap joint

For a frame joint far stronger than a miter, make it a half-lap by cutting away half the thickness of two boards where they overlap. A stacked-dado set hogs out the waste quickly and smoothly (below).

L shape joint, on top of one another

Here's how: Set your blade depth to slightly less than half the thickness of your workpiece. Position the rip fence so the distance between the far edge of the dado blade and the fence equals the width of the mating workpiece. After you cut the two mating pieces, check the fit; then sneak up to the perfect depth in succeeding cuts. (Like the tongue-and-groove joint, each adjustment doubles because it comes from both halves of the joint.)

Wide dado cut