Single-Dose Hopper for Breville/Sage Barista Express/Pro (simple, fully-printable)

Disclaimer

This hopper does not have much finger protection when installed. It is also easy to disengage the grinder lock when installing/uninstalling the hopper.

If you choose to use this, please only install/uninstall it with the machine off, and be careful.

I also encourage you to look into the food safety of your specific filament. Mine is printed with a random cheap PLA, and I will probably die a bit early for it.

Motivation

For a consistently good espresso, you need to be quite precise about the amount of coffee in your puck. The built-in dosing system in the Breville Barista Express is time-based and not precise enough for consistent results. Because of that, a lot of people stop filling up the hopper and weigh just enough beans for one dose, grinding through all of to achieve a more consistent result.

The original hopper, however, does lead to some of the half-ground coffee being retained above and around the burrs, resulting in some output inconsistency. On a more personal note, I have my machine on the countertop under a cupboard, and there's not a lot of clearance above the top of the original hopper, so loading it is a bit awkward.

There's a few single-dose hoppers available on here, notably this one: https://www.printables.com/model/80817-breville-barista-express-single-dose-hopper . For me though, that one fits a bit loose, and I also like the challenge of designing for no hardware and minimal moving parts.

Compatibility

Works with my Breville Barista Express BES870XL, should work for other Breville/Sage machines from the Barista line. Please let you know if you try it with one!

Printing and assembly

Just print each model upside-down, no supports or hardware required.

To assemble,

• Turn your machine OFF to prevent accidental grinder activation
• Remove the stock hopper
• Install the ring/clip: position it pins-up, the rigid side facing away from you, and slide the rigid-side pin into the further slot. Push the spring-loaded pin in and let it spring back into the other slot. It shouldn't activate the switch on the inside in its natural, “resting” position. 
• Position the hopper body with the bevel on the bottom, facing you. Push it into the hopper slot, twist a bit clockwise once fully in
• Et voilà!

Changelog

v2:

• Added a central hub to reduce popcorning and guide the beans better
• Improved fit and stability (added clip feet, more and stronger pins)
• Added a bit of knurling to the main body

Print settings

The tolerances here are pretty tight - please let me know if they turn out too tight for your printer!

The exact print settings shouldn't matter, however, as with most of my functional prints, I printed this with:

• PLA
• 0.4mm nozzle
• 0.3mm layer height
• 0.6mm max line width

Design files

The design is a public document in OnShape:

https://cad.onshape.com/documents/2da9f6a13e257962df9b1fb8