acrylic mods

three parts

Some surprises can be good, some surprises can be bad, and this one is great!

One of our most innovative customers Stephen Sweeney shared with us his mods to his HG one grinder. He’s been hard at work hand crafting beautiful acrylic bases that snap into place using rare earth magnets. Stephen’s created a set of parts for a Londinium I portafilter or for basket dosing with a 58mm basket. In addition he’s made a matching dosing funnel that can be used in both cases. Paul and I tried a few variations on this concept a while back, but our ideas pale in comparison to what Stephen has achieved. We were so excited by Stephen’s news, we had to share it with everyone.

While we don’t carry any of Stephen’s wonderful creations in our store, he is available for custom parts. Please reach out to Stephen directly at if you’re interested in commissioning work. Stephen’s a retired veteran who served our country with distinction. In addition, he’s a lovely gentleman and a real joy to correspond with. In his own words: I derive no profit in making these things, it is just a hobby to benefit the coffee community.

base copyIn order to take advantage of Stephen’s mods, the grinder has to be modified. A 1/2″ diameter hole will need to be drilled into the underside of the base of the grinder to fit a cylindrical rare earth magnet.

It’s highly recommended to use either a drill press or contact your local high school shop class if you don’t feel up to the task.

Notice that the hole isn’t in the center of the base, rather it is offset. Stephen will provide directions and the exact dimensions if you’re interested in ordering a kit. To note, also remember to match the polarity of the magnet in the base to it’s mated part.

Once the magnet in the base is installed, it’s smooth sailing from there. Paul’s a big fan of basket dosing and Stephen’s mod works incredibly well using this technique. The basket is removed from the portafilter handle and placed into the acrylic base. There’s a magnet located in the acrylic cradle which literally snaps the assembly into place directly below the lower funnel of the grinder. And using Stephen’s acrylic funnel, you can grind directly into the portafilter basket and redistribute the grounds prior to tamping.

basket and grinder copy

If basket dosing isn’t your cup of tea, you can use Stephen’s portafilter cradle. Based on his design, it only works with naked or bottomless portafilters, since the low profile of the cradle is unable to accommodate spouts. Once again his custom funnel is necessary, since you will need to redistribute the grounds before tamping. To note, the HG one grinder base is 8.5″ square, so chances are your portfilter handle will hang over the edge of the grinder.

pf and grinder copy

The magnets used in this mod are quite strong, and provide an excellent user experience. Both bases self center with a gratifying snap, and since the parts are acrylic, there’s little chance they will scratch or mar the surface of the grinder. As you can see in this image, the magnets are robust enough to hold the acrylic base to the surface of the grinder even when it’s tilted on it’s side.

strong magnet copy

And finally, while a picture’s worth a thousand words, a video must be worth a million.

A special thank you to Stephen, we honestly couldn’t have designed these parts better ourselves. Your work truly compliments the design of the HG one grinder, and the functionality is even more outstanding.