Cuanbian (攒边): Chinese Frame-and-Panel Tabletops

Cuanbian · Frame-and-panel · 攒边

Almost every Chinese tabletop, cabinet door and cabinet side is built the same way: a strong frame, and a thin panel that floats inside it.

The method is called cuanbian dacao zhuangban: assemble the edges (攒边), cut a groove (打槽), fit the panel (装板). It saves precious wood and lets the panel move with the seasons without splitting.

Chinese: 攒边打槽装板 · cuánbiān dǎcáo zhuāngbǎn
Joins: Frame members and panel
Found in: Tabletops, cabinet doors, cabinet sides, seat frames
Signature parts: Mitred frame · groove · panel tongue (边簧) · battens
Works with: Gejiao mitre, battens

Drag to rotate. Slide to take the joint apart, or press Assemble to watch it go together.

How it works

The frame

Two long sides (大边) and two ends (抹头) are joined at the corners with mitred tenons, so only a diagonal shows on top. The long sides carry the mortises, the ends the tenons.

Groove and tongue

A groove runs round the inside of the frame. The panel’s edges are thinned to a tongue, called 边簧, that sits in the groove.

Floating, not glued

The panel goes in without glue or nails and isn’t jammed tight, so it can swell and shrink with the weather. Battens slid into dovetail housings under the panel hold it flat, and their ends tenon into the long sides.

How it's made

Step 1
Groove the long sides
Cut the groove along the inner edge of the long sides, and the mortises for the ends.
Step 2
Tenon the ends
Mitre the ends and cut their tenons.
Step 3
Tongue the panel
Thin the panel’s edges to a tongue all round.
Step 4
Add the battens
Battens under the panel, their ends tenoned into the long sides.
Step 5
Set the panel in
The panel tongue goes into the groove, without glue.
Step 6
Leave room to move
The panel can move with the seasons; only a mitre shows at each corner.

Variations

Panel under a water-stop lip

Some tops have a raised lip round the frame with the panel set below it.

Seat frames

Chair seats use the same frame, with a woven soft seat instead of a panel.

Can you CNC this?

Possible, with design or setup changes

The 45° mitres and their tenons are cut with the frame members lying flat. The panel groove runs along an inside edge, which may need a slot cutter or the part on edge. The panel’s thin tongue is a simple rebate on the underside.

General note: a round cutter cannot leave a sharp inside corner, so every recess keeps the tool radius. Round the mating edges or add dogbone reliefs. Sloping faces, undercuts and curves may need special bits, extra setups or more axes.

Free STL downloads (one file per part)

Long side (front) 大边（前） · cuanbian-long-side-front.stl
Long side (back) 大边（后） · cuanbian-long-side-back.stl
End rail (left) 抹头（左） · cuanbian-end-left.stl
End rail (right) 抹头（右） · cuanbian-end-right.stl
Panel with battens 面心板与穿带 · cuanbian-panel-with-battens.stl

Proportions are illustrative, not measured dimensions. The files are unitless: scale them to suit and check fits and allowances before cutting. Each file is a closed (watertight) solid with its mortises and slots already cut, exported in its assembled position, ready to import into CAM or modelling software. Licence: CC BY 4.0 (credit: Chinese Joinery).