Setting simple of ThreadedHole to false does not work

[XCYRKDSDA]

This is the pillow block example from the docs. I changed the ClearanceHole to ThreadedHole, and set simple to False.

# Create the pillow block
with BuildPart() as pillow_block:
    with BuildSketch():
        RectangleRounded(width, height, fillet_radius)
    extrude(amount=thickness)
    with Locations((0, 0, thickness)):  # On the top
        PressFitHole(bearing=skate_bearing, interference=0.025 * MM)
        with GridLocations(width - padding, height - padding, 2, 2):
            ThreadedHole(fastener=cap_screw, simple=False)

But in the ocp_vscode window there were no threads in the result model.

I exported the pillow block into a .step file and opened it with freecad, still no threads, only simple holes.

[gumyr]

Thanks for raising the issue. This is actually a limitation of build123d as this ThreadedHole object does two things:
1- makes a hole by creating the hole object and combining it with the ongoing object with mode=Mode.SUBTRACT
2- make the thread which needs to be added to the ongoing object with mode=Mode.ADD (this operation will commonly result in invalid geometry generated by the OCCT CAD kernel)
but, build123d doesn't currently support chained operations like this.

Thread is very difficult for the OCCT CAD kernel to work with so I've found that the best way to work around this limitation is to create an assembly, in this case of the pillow block and the thread, which isn't something ThreadedHole can do by itself. Unfortunately there is no easy fix for this.

[XCYRKDSDA]

I'm not very familiar with mechanical design, but is it ok to make a threaded hole by subtracting a threaded screw? I find it produces an threaded hole that at least looks good.

[XCYRKDSDA]

Manually making a hole and adding IsoThread works. I'll just take it as a temporary solution.

Cylinder(2 / 2, 3, mode=Mode.SUBTRACT,
         align=(Align.CENTER, Align.CENTER, Align.MAX))
with Locations((0, 0, -3)):
    IsoThread(major_diameter=2, pitch=0.4, length=3, external=False,
              end_finishes=("fade", "fade"))