Wedged through tenon¶

from woodwright.examples import joints

design = joints.wedged_through_tenon(stile_length=750)

stile  600 x 60 x 20 mm  oak
       - through mortise 40 x 8 mm in back_edge
       - mortise flared 3 mm at the ends over 40, in back_edge
rail   360 x 60 x 20 mm  oak
       - tenon 40 x 8 mm, 60 long, 2 saw kerfs 2 mm, 40 deep, for wedges, on left_end
wedge  40 x 5 x 8 mm  oak, 2 pieces: wedge_1, wedge_2
       - taper 3 mm on back_edge towards right_end

def wedged_through_tenon(
    stile_length: float = 600,
    rail_length: float = 300,
    width: float = 60,
    kerf: float = 2,
    flare: float = 3,
    stock: Stock = OAK,
) -> Assembly:
    """A through tenon spread by two wedges into a mortise flared towards the outside.

    Two saw kerfs in the end of the tenon, near its edges, take the wedges;
    driven in, they bend the outer parts of the tenon out into the flares at
    the ends of the mortise, so the joint can't pull out even without glue.
    The mortise is flared along the stile, not across it, which would split
    it. The wedges are planed flush with the tenon; the stile stands with
    the tenon's end towards the viewer.
    """
    asm = Assembly("wedged_through_tenon", root_location=orient(right_end=UP, back_edge=LEFT))
    stile = asm.add(Board("stile", stock, length=stile_length, width=width))
    rail = asm.add(Board("rail", stock, length=rail_length, width=width))
    # As thick as the tenon, as long as the kerfs (two thirds of the stile),
    # at the head as wide as the kerf and the spread.
    wedge_stock = Stock.board(thickness=rules.tenon_thickness(stock.thickness), species="oak")
    wedges = tuple(
        asm.add(Board(f"wedge_{i + 1}", wedge_stock, length=width * 2 / 3, width=kerf + flare))
        for i in range(2)
    )
    asm.join(
        WedgedMortiseTenon(
            tenon=rail.left_end, mortise=stile.back_edge, shoulder=10, wedges=wedges, kerf=kerf
        )
    )
    return asm