Bit-sal

This engine recreates Bit-sal, where the slats are tilted 45° and woven diagonally inside the frame. The name comes from bit, "slanted," after the way the slats are set at an angle — the diamond grid formed by those crossing slats is the face of this changho. You set only the horizontal cell count; the vertical count is calculated automatically so the cells stay perfectly square, and there is no separate setting for the angle.

Characteristics

Cells are always fixed as squares, with slats laid along their diagonals to create the 45° pattern.
You cannot set the vertical cell count. It is derived automatically from the square cell size determined by the horizontal cell count and slat thickness.
Clipping keeps the slats from protruding outside the frame.

Main Parameters

Item	Description
Door type / panels	Hinged or sliding, 1–4 panels
Frame width / height	Wall opening dimensions (400–3,000mm). The outer panel size is calculated with the frame thickness removed.
Horizontal cells	2–30. The number of square cells across — this and the slat thickness set the cell size, and the vertical count follows automatically.
Auto-fit height	When checked, the frame height is adjusted so the last row meets the bottom rail exactly
Stile / rail thickness	Outer frame thickness (mm)
Slat thickness	Width of each slat (mm). It also determines the cell size (one side of the square).
Use transom panel	Adds a transom panel zone at the top when checked

Bit-sal has no zoning settings like the "vertical ratio" or "top/middle/bottom layout" found in Jeongja-sal and Se-sal. To change the grid density, adjust the horizontal cell count or the slat thickness.

Production Specification

Item	Description
Frame / outer / inner width and height	Automatically calculated measured dimensions
Horizontal / vertical layout lines	Spacing of the square cells, horizontally and vertically
Slat layout line	Distance between diagonal intersections
Half-lap width	Calculated equal to the slat thickness
Stile groove width	Slat thickness × (1 + √2) — the width of the groove the 45° diagonal slats cut into the frame

Parts List

Instead of horizontal and vertical slat groups, parts are listed as a diagonal slat group. Slats of equal length are bundled by each diagonal direction (↘ and ↗) and listed as length × quantity. Frame members, the transom panel (if used) and the door frame follow below.

Finish & Color

Wood, finish, hardware and the frame and slat colors are the same as Se-sal. Note that panel fill is currently disabled, so individual cells cannot be filled with color.

Layering Bit-sal with Jeongja-sal produces the more complex Gyeokja-bit-sal effect. See the Gyeokja-bit-sal page for details.

Example Uses

Lattice patterns for hanok lantern screens (bangdeung)
Contemporary interior screen partitions
Railing patterns for traditional pavilions