Portafilter.
The Minima comes with a single and a double spouted portafilter. As I can’t see me using the single I decided to convert it into a bottomless. Quite a easy job if you have access to a lathe, the whole process took me under and hour.
The biggest problem was removing the single spout from the head, it was TIGHT. So tight that I stopped trying to unscrew with the plastic handle for fear of breaking it. I looked around and found a bolt of the same thread, screwed that into the head and holding the single spout in the vice, unscrewed the head using a sturdy metal tube (originally from a sidecar chassis but other tubes are available) over the other end of the bolt for leverage. There is evidence of a locking compound on the thread, heat may have broken the bond but I found brute force to be quite effective. Opening out the hole is straightforward on the lathe and I deburred with a bearing scraper.
I value the bottomless portafilter much more than a single, and will use that in preference to the double.
Everything is working now, nothing left to do. I am having trouble dialling in the grind, mainly because I use the grinder for the Leva and change the setting for the daily Minima test shot. The minima needs a finer grind, especially after converting it with the flow device, otherwise the extraction is about 5-6 bar max on the Minima using Leva’s setting. I have dug out my old Rossi RR45 grinder and will use that exclusively for the Minima so I can avoid having to switch settings.
