Taoding Sun (套顶榫): Column Through the Base Stone
Taoding tenon
Most Chinese columns just stand on their stone bases, held by a short foot tenon.
Where a column needs real anchoring, the tenon goes much deeper: the taoding sun passes right through the stone.
- Chinese
- 套顶榫 · tàodǐng sǔn
- Joins
- Column foot through base stone to foundation
- Found in
- Columns needing extra stability
- Proportions
- Square, 1/2 of column diameter; length 1/5–1/3 of column height
- Compare
- Column-foot tenon
How it works
Through the stone
The column foot is cut to a long square tenon, half the column diameter on each side. It passes through a hole right through the base stone and the foundation pier, resting on a pad stone below.
How long
From 1/5 to 1/3 of the column height, set by how deep the foundation goes.
How it's made
Step 1Square tenon
Cut a square tenon half the column wide.
Step 2Long
1/5–1/3 of the column height.
Step 3Through hole
Cut a hole right through the base stone.
Step 4Set down
Pass the column through into the foundation.
Step 5Anchored
Used where columns need more stability.
Step 6Depth
Length set by the foundation depth.
Variations
Short foot tenon
The usual short tenon into a socket on top of the stone.
Can you CNC this?
Possible, with design or setup changes
The hole is through stone and into the foundation, so only the column is wood. The long square tenon on its foot may need the column clamped upright or cut from the sides in several setups.
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)
- Foundation 基础 · taoding-sun-foundation.stl
- Base stone 柱础石 · taoding-sun-base-stone.stl
- Column 柱 · taoding-sun-column.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).
Related joints
Questions
What is a taoding tenon?
A long column-foot tenon through the base stone into the foundation.
How big is it?
Half the column diameter square; 1/5–1/3 of the column height long.
Why use it?
For columns needing extra anchoring.