How to Cut Perfect Dadoes and Grooves on a Table Saw

You can tell a tidy shop by its joints. Dadoes and grooves—those clean, square channels that lock shelves, dividers, and panels into place—are the quiet heroes of strong, repeatable woodworking. A dado runs across the grain; a groove runs with the grain. Same three-sided trench, different direction. Get them right, and casework snaps together like it was meant to be. Miss by a millimeter, and glue-ups turn into wrestling matches.

This guide shows you how to cut perfect dadoes and grooves on a table saw—safely, precisely, and repeatably—using a stacked dado set or multiple passes with a single blade. We’ll cover setup, shimming for press-fit accuracy, tear-out prevention, stopped cuts, and the little calibration habits that separate “good enough” from “chef’s kiss.”

What are Dadoes?

A dado is a three-sided slot cut across the wood’s grain to receive another piece—often a shelf, divider, or panel—so the parts lock together with strength and automatic alignment. Picture a trench with two vertical walls and a flat bottom: that extra glue surface and mechanical capture make casework far sturdier than simple butt joints. Woodworkers cut dadoes with a stacked dado set on a table saw or with a router and straight bit; they can be through (running edge to edge) or stopped/blind (ending within the board). Depth typically runs about one-third to one-half the thickness of the host board, adjusted for the load and material. By contrast, when the same slot runs with the grain, it’s called a groove, and in British usage, a dado is often called a housing joint.

Tools & Materials

• Table saw in good tune (arbor true, blade 90° to table)
• Stacked dado set (outside blades, chippers, shims) or a single FTG blade
• Dado throat plate (wide opening) or zero-clearance insert for single-blade passes
• Crosscut sled or miter gauge with a long sacrificial fence
• Featherboards (fence and table) and push blocks
• Calipers (digital preferred) and a reliable square
• Pencil/marking knife, painter’s tape (for veneers), scrap for test cuts
• Optional: stop block, sacrificial rip fence, shop vac/dust collection

Safety Essentials

• Power down and unplug when changing blades or shimming.
• Use the dado throat plate; never run a stack in a standard insert.
• Remove the riving knife and blade guard only when required by the dado setup; re-install after.
• Keep hands well away—push blocks for narrow work, featherboards for control.
• Stand slightly to the side of the cut line; never directly behind the workpiece.
• No fence + miter gauge combo for crosscuts; use a stop block on a sled or the miter fence instead.

Dado vs. Groove: Which Is Which—and Why It Matters

• Dado (across the grain): bookshelf to side panels, drawer bottoms into sides, cabinet dividers. The cross-grain fibers are fragile—tear-out is more likely.
• Groove (with the grain): center panels in rails/stiles, long slots for backs or drawer bottoms. The grain supports the cut; the setup favors the rip fence with featherboards.

The geometry is identical, but workholding differs. Dados prefer a sled or miter gauge; grooves prefer the fence.

Choose Your Cutting Method

Stacked Dado Set (Best Accuracy, Fastest)

A quality stack lets you dial the exact width with chippers and shims. It has a flat bottom channel and crisp walls, perfect for production work and plywood.

Pros: Speed, flat bottoms, repeatability

Cons: Requires a throat plate, removing the knife/guard, and a higher cost

Single FTG Blade (Budget-Friendly, Great Results with Care)

Use a flat-top grind blade to avoid the little “bat-ear” ridges an ATB blade leaves. Make multiple passes (“nibbling”) to reach the final width.

Pros: No special hardware, safe with standard throat plate

Cons: More passes, the bottom may need a light clean-up

Planning & Sizing: Fit Beats Labels

Never cut to the number on the box. Plywood varies—“¾ in.” sheets often measure 23/32 in., sometimes a hair less. Solid wood can move. For a joint that sings:

Measure the actual thickness of the mating piece with calipers.

Decide your fit:

• Press fit (dry holds, glue needed): width equals stock thickness or +0.001-0.002 in.
• Slip fit (assembly ease, finish thickness): +0.004-0.008 in.

Record the target width. Cut tests in scrap from the same batch.

Setup: The Repeatable Routine

• Tune the saw: blade at 90° to the table, fence parallel, miter gauge at 90°, sled square.
• Install throat plate: dado insert for stacks; zero-clearance for a single blade.
• Blade height = groove depth. Typical depths:

Shelves: ⅜–½ in. deep in ¾ in. stock

Drawer bottoms: ¼ in. deep in ½–⅝ in. stock

• Reference face strategy: Mark a face and an edge as reference. Keep them against the fence or sled fence for every pass. Consistency cancels minor setup errors.

Cutting Dadoes

With a Stacked Dado Set

Build the stack:

• Use outside blades and chippers close to the target width; add paper/metal shims for the last thousandths. Tighten the arbor firmly.

Test and shim:

• Make a test dado in scrap. Try the mating piece. Too tight? Add a shim. Too loose? Remove a shim or swap a chipper. Label the final shim combo (e.g., “23/32 ply = 1/8 + 1/16 chipper + 0.010 shim”).

Workholding:

• Utilize a miter gauge or crosscut sled and a lengthy sacrificial fence. For repeated locations, clamp a stop block to the wall—never the rip fence—to avoid binding between blade and fence.

Cutting pass:

• Feed at a steady rate. The stack should hum, not screech or burn. Maintain even pressure against the fence. Support larger panels to prevent drifting.

Clean and inspect:

• The bottom should be flat, and the walls should be square. A few micro-ridges are normal—use a light chisel or router plane pass if you need glass-smooth.

With a Single FTG Blade (Multiple Passes)

Layout the width:

• Mark both walls of the dado. Set the fence so the right blade tooth kisses your first layout line.

Score the veneers (optional but wise):

• On veneered plywood, lay painter’s tape over the line or score with a marking knife to prevent splintering.

First “cheek” pass:

• Cut the first wall with the sled or miter gauge. Flip the board if needed to keep the reference face consistent.

Second cheek pass:

• Shift the fence/stop to the other layout line; make the second wall. You’ve now established the width.

Hog out the waste:

• Take a few passes between the cheeks. Slightly overlap each pass for a near-flat floor. Check fit; take hairline “sneak” passes as needed.

Cutting Grooves

Grooves love control. The rip fence sets position; featherboards lock the board for consistent depth and no wandering.

Fence & featherboards:

• Set the fence for the groove location. Use one featherboard on the table (before the blade) to hold stock down, and another on the wall to push stock in. Add push blocks for narrow stock.

Blade selection & height:

• Stacked dado for full width in one pass, or a single blade for a centered groove via two passes. Height = groove depth.

Centering trick (no math!):

• For a centered groove using a single blade, set the fence once and make a pass with the reference face against the wall. Then flip the board end-for-end, reference face still to the wall, and make a second pass. The groove automatically centers itself.

Through vs. stopped grooves:

• Through grooves are straightforward. Mark start/stop lines on the board and throat plate for stopped grooves. Lower the workpiece onto the spinning blade at the start mark, feed to the stop mark, then lift off (or better, use a router for delicate work).

Tear-out and veneer care:

• Tape and/or score the surface to protect fragile grain; ensure sharp cutters and a steady feed.

Notable Cases & Pro Techniques

Rabbets with a Dado Stack

Set the stack width to the rabbet width, add a sacrificial rip fence that rides just over the stack, and set the blade height to the rabbet depth. Run the stock with the reference face to the table and edge to the fence. Clean, square shoulders in two passes.

Housing Joints for Casework

For a flawless cabinet, cut matched dadoes on both sides with a stop block on the sled, then cut shelves to a press/slip target. Label depths so shelves bottom out uniformly—no rocking.

Stopped Dadoes (Safer Method)

Use a crosscut sled with a clamped stop in front of the blade. Start the cut against the stop, feed to your pencil line, and kill the saw with the workpiece in place. Let the blade stop, then withdraw. This avoids the sketchy “drop-on” move.

Veneered Plywood Without Tear-Out

• Blue tape across the cut line.
• Light scoring pass: Raise the blade high enough to kiss the veneer, run the line, then raise to full depth and finish.
• Fresh, clean teeth make the most significant difference.

Cleaner Bottoms with an ATB Blade

If you must use an ATB blade for multiple passes, take a shallow final “polish” pass or knock down ridges with a sharp chisel. Slightly slower feed reduces chatter lines.

Troubleshooting

• Joint too tight: Add 0.004–0.008 in. to width. With a stack, add a thin shim. With a single blade, bump the fence a paper-thickness and take a whisper pass on one wall.
• If the joint is too loose, Remove a shim or swap a chipper. With a single blade, reset the cheek lines closer and remake. If you’re already committed, consider glue and spline.
• Tear-out: Add a zero-clearance insert, score or tape, support with a sacrificial backer, and increase the feed rate slightly to let the tooth shear rather than pry.
• Ridges on the floor are regular with single-blade or poorly aligned chippers. Tighten the stack, reduce overlap gaps, or take a light final pass.
• Burn marks can be caused by a dull blade, pinching fences, or too slow a feed. Clean the resin pitch from the teeth and ensure the fence is parallel.
• Kickback scare: Stop using the fence with a crosscut and move to a sled/miter gauge and a stop block.

FAQs

What’s the ideal fit for plywood shelves?

For 23/32 in. plywood, aim for a slip fit of +0.004–0.006 in. so finish and humidity don’t fight you during assembly.

Do I need a dado stack?

No. A single FTG blade with careful layout and multiple passes produces excellent results. The stack makes it faster and flatter.

How deep should a dado be?

Common practice is ⅓ to ½ the thickness of the receiving board. In ¾ in. sides, ⅜–½ in. depth is robust without weakening the panel.

Are wobble dado blades worth it?

They’re inexpensive but tend to produce curved bottoms and chatter. A stacked set or multi-pass single blade is superior.

Can I cut stopped grooves on the table saw?

Yes—with start/stop marks, careful lowering/lifting, or the safer “stop-block and power-down” method on a sled. For exact stops, a router with a plunge base excels.

Workflow You Can Reuse

• Measure mating stock with calipers.
• Choose method: Stack or Single blade.
• Install the proper throat plate and set the blade height.
• Set up sled/miter gauge (dados) or fence + featherboards (grooves).
• Shim/test to target width; label the combo.
• Cut using the reference face
• Dry-fit and tune; then glue and clamp.

Suggested Shop Upgrades

• Dado throat plate matched to your saw; zero-clearance inserts for common widths.
• A calibrated shim set and a small case labeled with plywood brands/thicknesses are needed.
• Long sacrificial fences for miter gauge and rip fence; quick clamps for stop blocks.
• Featherboards with micro-adjust hardware; a dedicated crosscut sled if you don’t have one yet.

Conclusion

Precision with dadoes and grooves isn’t luck—it’s a ritual. You measure the reality of your stock, choose the method that matches your tools and tolerance for setup, lock in workholding, and sneak up on the fit with deliberate, almost boring test cuts. Do that, and the joint stops being unpredictable. It becomes repeatable, and repeatable is where good work turns into great work.

Think of the process as a small system you carry from project to project. Calipers live on the saw. A labeled shim kit rides with your dado stack. Your sled has a stop block that clamps quickly and securely. A card taped inside your cabinet lists “recipes” you’ve proven: 23/32″ maple ply, press fit → 1/8 + 1/16 chipper + 0.010 shim; blade at ⅜″. When you externalize the variables, you free up headspace. Now you’re building, not troubleshooting.

Fit is a strategic choice, not a guess. Casework that must self-align during glue-up? Aim for a gentle slip fit—room for glue and finish, zero drama under clamps. Fixtures, dividers, and shop jigs that you want rock-solid without clamps? Go for a careful press fit and dry-assembly confidence. Seasonal movement, finish thickness, and project scale all influence that decision. Name your fit before you touch the fence.

Quality control happens before the glue comes out. Dry-fit every shelf, confirm depth and shoulder cleanliness, and check parallelism at the dado’s lips with a square. If something’s off, resist the urge to “make it work” with clamps. Thousandths matter here because errors stack: a hair loose on one shelf and a hair shallow on the next can tilt a whole case. It’s faster to fix the joint than to fight the glue-up.

Safety is the constant bassline under all this. A proper throat plate, thoughtful stance, push blocks, and the discipline to never mix the fence with the miter gauge on crosscuts aren’t fussy rules; they’re the reason you get to keep building tomorrow. When a cut feels sketchy, it is. Stop, rethink, jig it, or move to a router where plunge and stops are safer for what you’re trying to do.

Expect some troubleshooting. Veneer tears? Score and tape. Ridges on the floor? Tighten the stack or take a whisper pass. Burn marks? Clean the teeth and check the fence for pinching. Keep a small notebook with the “why” and the “fix.” In a month, you’ll have your own shop-specific playbook, saving you hours.

From here, the skill ladders naturally. The same control you’ve built for dadoes powers perfect grooves for frame-and-panel work, dead-square rabbets for the backs of cabinets, and bulletproof housing joints in bookcases. Add a sacrificial fence, and you’ll cut dialed-in rabbets. Add a stop system to your sled, and you’re making perfectly mirrored case sides. Precision compounds.

Before you leave the shop, do a 30-second teardown: re-install the riving knife and guard, vacuum the insert, note the winning shim combo, and toss your test offcuts into a labeled bin (they become tomorrow’s setup pieces). That tiny bit of closure keeps your next session frictionless.

In short: measure what is, not what’s printed; control the work, not just the blade; decide the fit, then cut toward it; protect the fibers; and keep the process consistent. Do this, and your dadoes and grooves will stop being “operations” and become assets—clean, square, confidence-inducing joints that make your assemblies slide together and your finished pieces look intentional from every angle.