Picture of Making a bottomless portafilter
Inspired by asc2 asking on my homemade tamper instructable if my bottomless portafilter was a DIY project I grabbed a spare portafilter and headed to techshop to see if I could successfully lop the bottom off.  This is a pretty simple project if you've got access to a metal lathe.  I don't have one at home so I made it at techshop.

Step 1: Disassemble the portafilter

Picture of Disassemble the portafilter
Start by clamping the portafilter in a vise and unscrewing the handle.  The factory was nice enough to use loctite or something similar so it was a pain to disassemble it.  I was worried that I would ruin the handle so I brought along a rosewood handle that I made a few months ago.  I think if the plan was to keep the same handle I would clamp the body of the portafilter in the vise with a scrap of wood on each side to prevent it from getting all banged up.
silver552 years ago
Job well done, but I did not understand what good is a filter holder without the bottom.

Translated from Italian by Google
Super Doug2 years ago
Cool project Foodgeek! A couple of questions.
~ did the lathe chuck mare the finish on the PF?
~ what speed did you use to turn the bottom out?
~ is cutting fluid (coolant) required for making a cut like this?

Again, great stuff!
FoodGeek (author)  Super Doug2 years ago
Thanks :)

I ended up more like gorilla tight than monkey tight with the chuck but didn't really scratch up the finish. I used something like 460rpm. I sprayed some coolant on the piece but I suspect you could get away without it. This portafilter is a big chunk of brass so it's easy to machine and it's a good heat sink.