cheese grater pattern in build123d

cheese-grater.py

import logging
import math
from build123d import *
logging.basicConfig(level=logging.WARN)
from yacv_server import show

# %%

hole_diameter = 20
board_x, board_y = 400, 120
board_thickness = hole_diameter * (0.5 + 0.1)
board_holes_margin_x, board_holes_margin_y = 60, 20

board = extrude(
    Rectangle(board_x, board_y),
    amount=board_thickness,
)
board_bottom_plane = Plane(board.faces().sort_by(Axis.Z).first)
board_top_plane = Plane(board.faces().sort_by(Axis.Z).last)

hole_x_spacing = hole_diameter * 23 / 20
hole_y_spacing = hole_diameter * 1.0
holes_x_count = math.floor((board_x - 2 * board_holes_margin_x) / hole_x_spacing)
holes_y_count = math.floor((board_y - 2 * board_holes_margin_y) / hole_y_spacing)

hole = Sphere(hole_diameter / 2)

holes_b_row_x_offset = hole_diameter * 11.5 / 20
holes_b_row_y_offset = hole_diameter
def HolesCenters(plane, x_count = holes_x_count, y_count = holes_y_count):
    holes_centers_a = [
        plane
        * hole_center
        for hole_center in GridLocations(
            x_spacing=hole_x_spacing,
            y_spacing=hole_y_spacing * 2,
            x_count=x_count,
            y_count=math.ceil(y_count / 2),
            align=(Align.MIN, Align.MIN)
        )
    ]
    holes_centers_b = [
        plane
        * Pos(holes_b_row_x_offset, holes_b_row_y_offset, 0)
        * hole_center
        for hole_center in GridLocations(
            x_spacing=hole_x_spacing,
            y_spacing=hole_y_spacing * 2,
            x_count=x_count,
            y_count=math.floor(y_count / 2),
            align=(Align.MIN, Align.MIN)
        )
    ]
    return holes_centers_a + holes_centers_b

holes_top_x_offset = board_x * -.5 + board_holes_margin_x + hole_x_spacing * .5
holes_top_y_offset = board_y * -.5 + board_holes_margin_y + hole_y_spacing * .5
holes_top_plane = board_top_plane.move(Pos(
    holes_top_x_offset,
    holes_top_y_offset,
    0
))
top_holes = [
    hole_center
    * hole
    for hole_center in HolesCenters(holes_top_plane)
]

holes_bottom_x_offset = holes_top_x_offset - holes_b_row_x_offset
holes_bottom_y_offset = holes_top_y_offset - hole_diameter * 7 / 20
holes_bottom_z_offset = hole_diameter * 12 / 20
holes_bottom_plane = board_top_plane.move(Pos(
    holes_bottom_x_offset,
    holes_bottom_y_offset,
    -holes_bottom_z_offset,
))
bottom_holes = [
    hole_center
    * hole
    for hole_center in HolesCenters(holes_bottom_plane, holes_x_count + 1, holes_y_count + 1)
]

model = board - top_holes - bottom_holes

show(model)

# %%