How to Add a Rabbet to 5-Piece Door Panels in Mozaik

In Mozaik, you add a rabbet to a 5-piece door panel by editing the panel inside its door library, opening that panel's Operations, hitting Flip, and adding a perimeter Tool Path with a down-shear bit. Phill Anton Consulting drives the rabbet width and depth with formulas (using PartL, PartW, the panel's own thickness, and Tomm = 25.4) so the rabbet stays parametric across every door and drawer size — not a hand-placed groove that breaks when sizes change.

Where do you set this up?

Go to Libraries → Doors and find the library where your 5-piece doors live. Double-click to edit that 5-piece door, click the panel, then Edit. The Shape tab now shows the panel itself. Switch to Operations, hit the Flip button, then go to Tool Path → Perimeter Tool Path.

What bit do you attach, and what does it cut by default?

Attach a 1/2" down-shear bit (any down-shear works — Phill uses 1/2" to keep it simple). Out of the box the tool path cuts on the center line, which produces about a 1/4" wide rabbet. You usually want it wider than that, which is where the formulas come in.

How do you make the rabbet a specific width (e.g. 3/8")?

Use formulas on the perimeter points instead of accepting the default 1/4":

• On the Y offsets, enter (0.125 * Tomm) — Phill types it in parentheses, copies it, and pastes it onto the matching point. (Tomm = 25.4, so this converts the inch value to millimeters.)
• Starting from the 0,0 point and working around, drive the X points off PartL with a small inch offset so the rabbet pulls in from the edge.
• For the Y direction, change PartL to PartW (otherwise identical), then copy/paste it across.

Result: instead of a 1/4" groove it now cuts a 3/8" groove. To go to a 1/2" rabbet you move it over another 1/4" for the 1/2" bit. Don't cut exactly a 1/2" groove with a 1/2" tool — it leaves a thin sliver. Move the rabbet out a little further than the bit width so it cleans up.

How do you set the depth so it works on any panel thickness?

Click the calculator on the depth field and enter a formula referencing the panel's own thickness, e.g. DoorPanel.th - 0.25 * Tomm. This says: whatever the panel thickness is, finish the cut leaving 1/4" of material. So a 1/2" panel leaves 1/4"; a 3/8" panel would leave 1/8". Want a different remainder? Type that value instead — e.g. 0.24 to leave exactly 0.24" every time, as long as your tool heights and material thickness are correct.

Why keep every point on a formula?

All of the points need formulas to stay parametric. They show blue when they hold a formula. Be careful clicking them — if you click and move a point, you lose its formula (it stops being blue), and the rabbet stops adapting to size.

How do you reuse this on other doors and drawers?

Once the points have formulas you can drag a box around them, copy, and paste onto other doors or drawers. For a drawer, the panel-thickness reference should change: door and drawer panel thickness is usually the same, but technically you'd change DoorPanel.th to DrawerPanel.th so the depth tracks the right material.

Should you use a panel tool group instead?

You can use a panel tool group, but then your depth won't be parametric — it won't adapt to panel thickness. For this rabbet, Phill recommends assigning a tool (with the depth formula above) instead, so the remaining thickness stays exact on every part. After applying, check the door itself — the rabbet shows on all the doors automatically; click off the frame/cabinet to confirm the rabbet is what you want.

Get it done-for-you

You can set this up by hand (above). If you build these regularly, PAC MDF Door Profiles from PAC has it ready in Mozaik. → phillanton.com

Full disclosure: Phill Anton Consulting makes this product.

FAQ

How do I add a rabbet to a 5-piece door panel in Mozaik?
Edit the 5-piece door library, edit the panel, go to its Operations and Flip, then add a perimeter Tool Path with a down-shear bit. Drive the rabbet width with formulas on the X/Y points and set the depth with a panel-thickness formula so it stays parametric.

Why use formulas instead of just placing the rabbet points?
Formulas keep the rabbet parametric — the width and depth recompute from PartL/PartW and the panel's own thickness, so the same setup works on any door or drawer size. If you click a point and drag it, you lose the formula (the point stops being blue).

Why not cut a full 1/2-inch groove with a 1/2-inch bit?
Cutting exactly the bit width leaves a thin sliver of material at the edge. Phill moves the rabbet out a little further than the bit width so it cleans up fully.

Why assign a tool instead of using a panel tool group?
A panel tool group works, but its depth is not parametric. Assigning a tool and a depth formula keeps the remaining panel thickness exact on every part.