Hey guys

I'm looking into having a bottomless PF machined for my Zerowatt machine. To do this i will of course need the measurements of the PF and i was hoping that someone on HB could help me. It seems to me that the measurements needed are:

Inner diameter
Outer diameter
Outer diameter with the "ears"
Height of the ears at the beginning and end
Length of the ears
Total height of the PF(since it will be a bottomless one, i guess the height of the PF "walls" are all that is needed)

Someone with CNC experience are welcome to correct me if i've misunderstod something, but it seems that simplest way to make this is by machining a cylinder with the "ears" and then weld on a couple of cm of threaded bar to fit the handle. I'm guessing this would be easier than having to actually machine the bar with the cylinder as one piece. I'm aware that welding this on would probably be rather ugly, but i'm only interested in getting a working Pf, not a nice looking one.

I wonder if a 3-D scan would help this project, especially if that scan can be made open source?

That would be perfect! That would also make it a lot easier to visualize and share the idea with people who might not know anything about portafilters. If we could somehow scan some of the "lost" portafilters we could make it a lot easier to get older machines up and running! I assume it would also make it possible to make prototypes on 3D printers?
Only problem is, is there anyone here who is able to scan the PF and got a PF?

Why weld? With a CNC machine a lug could probably be made pretty easy, allowing you to drill and thread it and screw in the handle.

It may be good to add the mode and yearl as there are a few Zerowatt machines, and it is not clear to me if they all use the same PF.

I'm just going to move away from the possibility of making a PF, because I think I just solved the problem!! I thought why not and checked if a PV PF will fit AND GUESS WHAT? IT F*CKING FIT!




Here you see the shower screen of the zerowatt with the basket of the PV over it, both with and without the gasket. With the gasket the ears of the PF is a bit too large. I could probably file it down on a new PF, but I guess it would be easier to find a gasket that is a bit smaller?

Is it completely crazy to sand down a gasket, to reduce it's height? I can't imagine that cutting it would be a good idea, since it probably wouldn't result in a level proper seal.

Should work, just give it a try...

CoffeeBeetle wrote:Is it completely crazy to sand down a gasket, to reduce it's height? I can't imagine that cutting it would be a good idea, since it probably wouldn't result in a level proper seal.

I did exactly that and it worked. Congratulations on solving the missing portafilter problem for these orphaned machines!

This is also a fix for Brunellas that lack PFs. Get a PV portafilter and then reduce the height of the PF gasket (or shave the PF if you prefer the more difficult approach).

Good to know. I've heard that the Brunella is a capable little machine as well and it would be a shame to miss a cheap one, just because it's missing a PF.

I've got the Zerowatt up and running using several layers of paper as shims. Don't know how long that will work but it should give me some time to actually make some espresso with it. Speaking of which, holy sh't! I thought it would be decent when everything was done right, but after 2 shots to dial in it just make an amazing shot! It can easily compete with my Zacconi Riviera.
So far the main problems are the looks of it(very few things look good in beige i guess) and the fact that the air under the piston is pushed out of a small "exhaust pipe" in the top of the machine when the lever is pulled down, always taking a bit of near boiling water with it that always lands on the barista's arm. There is no way the designer of this machine used it more than a few times before green-lighting this feature.