Gridfinity Gram Calibration Weight

I stumbled upon these awesome bins  implemented in CQ by @jdegs. And I had just purchased (accidentally) two sets of these calibration weights for a microgram scale. And, being a devotee of Gridfinity, I had a natural need that I could find no other files out there that met my needs.

So, I first took the pre-rendered 1x1x4 bin with no magnets (not a magnet user). Then I sliced out the center and added five holes for the weights manually (see prototype). The holes aren't the full depth of the weight to reduce filament use, but deep enough to prevent the dreaded jumping out of place.

Then I dove into CQ and brought my Python knowledge to bear. An aside, I'm loving CQ. It works better for me than all other methods I've tried to date (Tinkercad, Fusion360 (at least it was a free trial), FreeCAD, Blender).

So I re-implemented my prototype in CQ, basing it on @jdegs's python file. The file is fairly constrained to my niche use, (so 1x1 and 4 units high). There is some flexbility in the dimensions of the weights, and height of the cup. I did 4 units as it allows me to still nest them in my drawer.

I also turned the initial file into a reusable module for future use. And that's included as well. I had good success using the specific CQ release instance linked to in the original posting.

The key items in the file are:

minimum_holder_thickness = 8 #mm of base to leave
# Have the holes use the bottom socket area
# This does cut down on extruded material at the sacrifice of strength
utilize_bottom_socket = True 
weight_definition = {
    "one": {
        "diam": 14.25,
        "height": minimum_holder_thickness
    },
    "two": {
        "diam": 11.25,
        "height": minimum_holder_thickness - 2
    },
    "three": {
        "diam": 9,
        "height": minimum_holder_thickness - 2
    },
    "four": {
        "diam": 7.25,
        "height": minimum_holder_thickness - 3.2
    },
    "five":{
        "diam": 7,
        "height": minimum_holder_thickness - 5.3
    },
}
#....
#....
#....
f8 = make_weight_holder(weight_definition,
                        unit_height = 4,
                        min_holder_thickness=minimum_holder_thickness,
                        use_bottom_socket=utilize_bottom_socket)

Most of the math is done via the Python dataclass BoxDims.

I hope this is helpful for all you out there. And special thanks to @jdegs for inadvertently putting me onto CQ!

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Also, please ignore my artifacts in the prints. I was purposefully pushing my printer as hard and fast as I could while I iterated on the design.