kitchen roll / paper towel holder

Depending on the accuracy of your printer you might have to change the leeway variable for the fixture piece (for retesting you only need to print the fixture).

I used 4mm x 10mm rod magnets which are pressure fit into the print. If you have other magnets at hand you can adjust the following variables: mgd (magnet diameter with leeway) + mgl (magnet length with leeway) and also maybe mz (mount base height) if your magnet has large diameter.