Dowel tusk tenon¶

from woodwright.examples import joints

design = joints.dowel_tusk_tenon(leg_length=625)

leg        500 x 70 x 70 mm  oak
           - through mortise 100 x 45 mm in back_edge
stretcher  540 x 240 x 45 mm  oak
           - tenon 100 x 45 mm, 140 long, end chamfered 2 mm, corners chamfered 20 mm, on left_end
           - 2 holes ø20 for tusks through the tenon on left_end, parallel to leg.front_edge, 8 mm off it
tusk       ø20 x 100 mm  oak, 2 pieces: tusk_1, tusk_2
           - flat taper 4 mm over 50 on front_edge towards right_end
bearing    ø20 x 100 mm  oak
           - flat 20 mm wide, 10 deep, on front_edge

def dowel_tusk_tenon(
    leg_length: float = 500,
    stretcher_length: float = 400,
    width: float = 240,
    tusk_diameter: float = 20,
    tusk_length: float = 100,
) -> Assembly:
    """A tusk tenon held by dowels (after Rex Krueger's workbench): a wide
    stretcher through a 70 mm square leg, held by two tapered dowels through
    its tenon, level, their heads towards the viewer.

    The 45 mm thick stretcher's tenon is as thick as the stretcher and 100
    mm wide, standing out of the leg by as much as the leg is wide, with big
    chamfers at its corners. The tusks, `tusk_diameter` dowels `tusk_length`
    long, have flats planed over their tip halves, tapering 1:12.5, and go
    through straight holes in the second and the fourth fifth of the tenon;
    behind the tenon their flats bear on the round top of a half dowel
    glued flat side down across the leg. Knocked out, the tusks free the
    stretcher.
    """
    asm = Assembly("dowel_tusk_tenon", root_location=orient(right_end=UP, back_edge=LEFT))
    leg = asm.add(Board("leg", POST_STOCK, length=leg_length, width=POST_STOCK.thickness))
    stretcher = asm.add(Board("stretcher", LEG_STOCK, length=stretcher_length, width=width))
    dowel = Stock.rod(diameter=tusk_diameter, species="oak")
    tusks = tuple(asm.add(Rod(f"tusk_{i + 1}", dowel, length=tusk_length)) for i in range(2))
    tenon = 100
    bearing = asm.add(Rod("bearing", dowel, length=tenon))
    asm.join(
        DowelTuskTenon(
            tenon=stretcher.left_end,
            mortise=leg.back_edge,
            position=offset(60, ref=leg.right_end),
            across=CENTERED,
            shoulder=(width - tenon) / 2,
            tenon_thickness=LEG_STOCK.thickness,
            tenon_chamfer=2,
            tenon_corner_chamfer=20,
            tusks=tusks,
            bearings=(bearing,),
            tusk_head=leg.top_face,
            tusk_slope=12.5,
            protrusion=POST_STOCK.thickness,
        )
    )
    return asm