build123d-utils-jas

Personal build123d utilities, extracted from a pile of CAD projects that each carried their own diverging copy.

uv add build123d-utils-jas            # core
uv add 'build123d-utils-jas[fasteners,preview]'  # + FastHeatSetNut, + ocp_vscode viewer

Supports build123d >=0.11. Developed and tested against both the latest release and a pinned build123d dev revision (see [tool.uv.sources]).

Modules

fast_patch — faster Shape operations

Monkey-patches Shape.__copy__/moved/located/_apply_transform/fix/ bounding_box to skip revalidation and share the underlying TopoDS_Shape. bounding_box also defaults to the fast non-optimal OCC box with a coarse tolerance. Nothing happens at import time — opt in explicitly:

from build123d_utils_jas import apply_fast_patch, no_fast_patch

if __name__ == "__main__":
  apply_fast_patch()

with no_fast_patch():
  ...  # stock build123d behavior restored for this block

helpers — geometry helpers

from build123d_utils_jas import align, lift, raise_to, offset_to, extrude_to, CENTER, MIN, MAX

part = align(part, (CENTER, CENTER, MIN))       # bounding-box alignment to origin
plane = offset_to(Plane.XY.offset(3), bb.max.Z)  # offset a plane to an absolute coordinate
extrude_to(heatsink_bb.min.X)                    # extrude pending sketches to an absolute coordinate

Also flip, shell_loft, make_solid (solid from shells, holes supported), and convex_face_from_points (planar face from a point cloud's hull).

assembly — labeled compounds

from build123d_utils_jas import make_compound, find_part

a = make_compound(label="lamp", base=base, wago=[w1, w2])
find_part(a, "wago")      # -> [wago_0, wago_1]
find_part(a, "cap.can")   # dotted paths descend into nested compounds

vendor — cached STEP imports

from build123d_utils_jas import import_vendor, set_vendor_dir

set_vendor_dir("vendor")  # the default; resolved against the cwd
cob = import_vendor("XLamp CMA1303.STEP", rot=(90, 0, 0))

STEP files are cached on disk as BREP keyed by content hash (vendor/cache/<file>/<sha256>.brep) and memoized in-memory per process, so re-running a script re-imports nothing that didn't change.

viewer — ocp_vscode wrappers (opt-in)

show_object, push_object, show_objects, reset_show are no-ops until init_viewer() is called, so batch runs and imports never need a viewer. Requires the preview extra when actually used.

printing — FDM printability

fix_horizontal_holes(shape) finds horizontal-ish cylindrical/conical bores and cuts their tops into self-supporting flat-roof teardrops, leaving the load-bearing part of the bore round.

fasteners — FastHeatSetNut

A bd_warehouse Nut for heat-set inserts with knurling removed for fast generation, plus a fill_factor property (insert volume vs. hole volume). Requires the fasteners extra.

AI use

AI (Claude) was used to manage the extraction of these utilities from their original per-project copies, and assisted in writing parts of the code. Design decisions and the original implementations are my own.

License

MIT