Mitred frame and panel¶

from woodwright.examples import frames

design = frames.mitred_frame_and_panel(width=750)

left_right  450 x 60 x 20 mm  oak, 2 pieces: left, right
            - mitre 45 deg on right_end, back_edge inside
            - mitre 45 deg on left_end, back_edge inside
            - groove 6 mm, 12 deep, in back_edge
top_bottom  600 x 60 x 20 mm  oak, 2 pieces: top, bottom
            - mitre 45 deg on left_end, back_edge inside
            - mitre 45 deg on right_end, back_edge inside
            - groove 6 mm, 12 deep, in back_edge
panel       500 x 120 x 12 mm  oak, 2 pieces: panel_1, panel_3
            - tongue 6 mm thick, 10 long, on left_end
            - tongue 6 mm thick, 10 long, on right_end
            - tongue 6 mm thick, 10 long, on back_edge
panel_2     500 x 110 x 12 mm  oak
            - tongue 6 mm thick, 10 long, on left_end
            - tongue 6 mm thick, 10 long, on right_end

def mitred_frame_and_panel(
    width: float = 600,
    height: float = 450,
    member_width: float = 60,
    boards: int = 3,
    tongue_length: float = 10,
    clearance: float = 2,
    stock: Stock = OAK,
    panel_stock: Stock = SIDE_OAK,
) -> Assembly:
    """A frame mitred at the corners, a panel glued up from `boards` boards
    tongued into a groove along its inside edges; outside sizes.

    The members are mitred as in a picture frame; the grooves run through
    them and out at the mitres, where they meet and are hidden. The boards
    run along the width, butt-joined edge to edge; the ends of all of them
    and the outer edges of the outer ones are tongued into the grooves. The
    panel's design size is the opening of the frame, the tongues add to it;
    it is centered in the frame's thickness and not glued in, the grooves
    `clearance` deeper than the tongues so that it can swell.
    """
    asm = Assembly("mitred_frame_and_panel", root_location=STANDING)
    left = asm.add(Board("left", stock, length=height, width=member_width))
    top = asm.add(Board("top", stock, length=width, width=member_width))
    right = asm.add(Board("right", stock, length=height, width=member_width))
    bottom = asm.add(Board("bottom", stock, length=width, width=member_width))
    members = [left, top, right, bottom]
    # Going round from the bottom of the left member, the back edges inside.
    for a, b in zip(members, members[1:] + members[:1], strict=True):
        asm.join(MitreCorner(a.right_end, b.left_end, a.back_edge, b.back_edge))
    board_width = (height - 2 * member_width) / boards
    panel = [
        asm.add(
            Board(f"panel_{i + 1}", panel_stock, length=width - 2 * member_width, width=board_width)
        )
        for i in range(boards)
    ]
    # The boards' front edges up (their reference faces are at the back).
    for a, b in itertools.pairwise(panel):
        asm.join(Butt(a.front_edge, b.back_edge))

    def tongue(edge: SideRef, groove: SideRef, position: Position = CENTERED) -> None:
        asm.join(
            TongueAndGroove(
                tongue=edge,
                groove=groove,
                tongue_length=tongue_length,
                position=position,
                across=CENTERED,
                clearance=clearance,
            )
        )

    # From the bottom up; the left member's left end is at the bottom, the
    # right member's right end.
    for i, board in enumerate(panel):
        below = member_width + i * board_width
        tongue(board.left_end, left.back_edge, offset(below, left.left_end))
        tongue(board.right_end, right.back_edge, offset(below, right.right_end))
    tongue(panel[0].back_edge, bottom.back_edge)
    tongue(panel[-1].front_edge, top.back_edge)
    return asm