Skip to content

Half lap t

joints.half_lap_t

A T-shaped half lap: a lap on the end of the rail, a dado across the stile.

Half lap t, assembled

Half lap t, exploded

Parameters

Parameter Default
stile_length 300
rail_length 200
width 40
stock 20 mm board, oak

Change them in a design file (see Change an example):

from woodwright.examples import joints

design = joints.half_lap_t(stile_length=375)

Drawings

The plans in one PDF: plans.pdf.

Assembly

assembly

Parts

parts

Rail

rail

Stile

stile

Cut list

stile  300 x 40 x 20 mm  oak
       - dado 40 mm, 10 deep, in bottom_face
rail   240 x 40 x 20 mm  oak
       - lap 10 mm thick, 40 long, on left_end

Code

From woodwright/examples/joints.py, which imports the names it uses (see From an example to your own design):

def half_lap_t(
    stile_length: float = 300, rail_length: float = 200, width: float = 40, stock: Stock = OAK
) -> Assembly:
    """A T-shaped half lap: a lap on the end of the rail, a dado across the stile."""
    asm = Assembly("half_lap_t", root_location=STANDING)
    stile = asm.add(Board("stile", stock, length=stile_length, width=width))
    rail = asm.add(Board("rail", stock, length=rail_length, width=width))
    asm.join(HalfLap(lap=rail.left_end, socket=stile.back_edge))
    return asm

Exported with woodwright 0.9.0 on 2026-10-25.