customizable canister cap wrench [OpenSCAD]

To use this script with full functionality, you need a development version of OpenSCAD with the roof function enabled. There is also a variant for the stable release (currently 2021.01) but it  will not create a bevel inside the hole for the cap.

Some cleaners / detergents come in canisters with very tight caps from the factory. I'm not writing about these for distilled water or screen washer fluid but the sturdier ones for chemicals. It can be quite hard to open them without the proper tool. About three years ago I was so done with it, that I created the initial version, printed a few wrenches and forgot about. The old version might be on thingiverse or cults3d but I don't think I ever published it. I haven't been active there for quite a while now. The contest reminded me of this old script and was the perfect excuse to refine and publish it. Hopefully it's helpful for someone.

The printed key in the pictures is the same as the supplied example but without the text (all the default settings from the script). It fits perfectly on my 5l chemdiscount canisters.

• There are two options to measure the length of the ribs. For even counts it's easier to just measure the outer diameter. With odd counts, it'll be better to measure how far they stand out from the cap. I made a sketch with the required dimensions of the cap as image and also as svg. If the image is enough, you won't need the svg.
• All parameters are commented 
• The supplied model uses all the default parameters except for the text. There is a screenshot with most parameters
• The rounding on the outside is based of the height of the wrench. It's the max added size to the outer dimensions. The larger the percentage the smaller the radius will be (it's calculated). That will also make overhangs more difficult to print

Updates:

2025-07-12: 
New reinforcement options. This will create a tiny internal cavity around the cap opening. This is an easy way to force additional perimeters in this spot without modifiers (see slicer screenshot). If it doesn't work you can increase the size or check the gap filling options of your slicer.