Breville Bambino razor tool

Breville includes a so-called “razor” tool with the Bambino Plus for leveling the amount of coffee in the portafilter.  Being cheapskates, they leave it out of the smaller Bambino model even though it's a few cents of metal material.  This is designed for 54mm portafilters.  You can scale it to match any other size if you want.

I took a picture online and modeled it myself with a couple of small improvements in the “blade” geometry.  Note that you will require support material for the underhanging blade, unless you somehow get it to print standing with the blade up. For those who have a multi-material printer like an XL, I had great results printing with PLA for the body and using PETG supports with zero gap.

Once you print it, you would use it to spin around in the coffee filter AFTER tamping to leave the correct amount of coffee.  I made this as a STEP file after getting annoyed at the number of people uploading low-quality STLs, especially for detailed geometry such as the sharp edge.  This way, you can import directly into any slicer at full quality.