So, I've modified my Faema MC (again, see Faema MC) by severely decreasing the output hole size of the grind chamber with some thin translucent plastic sheet and fitting an acrylic tube in the throat with a plunger in it. This allows me to pump out the leftover grinds, (or pump while grinding for especially sticky grinds).

The result is a big conical that is almost retention-free (what retention there is is downstream of the grind chamber exit, mostly in the funnel), without resorting to cocking about with brushes in the throat. Especially on the MC, that is a royal pain since the throat is xbox hueg.

Video and pictures should explain. I'm quite pleased with how it works, less so with the aesthetics, but that wasn't the primary concern when cobbling this together. The setup has seen a few iterations, and this is the first that works well enough.

This is the plunger inside the acrylic tube. 'gaskets' are made from cotton bar tape. This works because it's not sticky and airtight enough for the intended use. The gasket between the acrylic tube and the grinder throat is made from the same stuff.


Firstly, I tried to decrease the hole size with Sugru, but the hole was still way too large, so I glued in place that sheet of plastic as I was out of sugru. The resulting hole should be small enough to give a large enough pressure differential, but big enough to let the grinds out. This took some trial and error to figure out. A good tip would be to start small and gradually increase the hole size until it works. Note that I've sanded smooth what's left of the throat.
The grounds are thrown to the left in any case due to the rotation of the sweeper vanes in the burr chamber, so it makes sense to make the hole larger more to the left of the throat. Of course, this is not an issue if you would fill up the entire throat with something like sugru/3dprinted plug, but when using a piece of plastic like I have the grounds will 'impact' the left side of the throat and stick there more. It's a good idea to have most of the surface area of the created throat closer to the edges of the throat as grinds tend to stick there more.

And a small video of the air blast in action. If the grounds are more sticky, it works better to pump while grinding, which also saves a few precious seconds. But I couldn't film that as I've just got two hands and I need to hold the catch cup in my hand.

I love this mod. I've heard someone say they used a rubber ball with a string on it and jammed it down the grinder throat. I ordered one to try out, but haven't yet got it. If that doesn't work I'll try to go for something like this.

Cotton bar tape looks nice though it does seem to pick up coffee grounds if I'm seeing it right, other than the threaded rod, what material did you use for the piston headers as it were?

Overall great mod!

Thanks!

The pistons are some pvc bar stock I bought at the same place as the acrylic pipe.
The bar tape does pick up some grounds, because when pumping upwards, some small grind particles are also sucked up the tube. So far, no interference or foul smell, and I've been using them for a month now.

Could swear I saw someone else adapt something like the rubber part of a turkey baster to squeeze and purge out grinds also

What about:
http://www.amazon.com/Products-MPS4-Mas ... 005UJLVGI/

or more hilariously in the kitchen:
http://www.amazon.com/WM-Harvey-090360- ... 000UFP5NC/

...it is designer...

Lol

This a neat solution. Well done!
On my old Faema A6 a silicone patty pan worked really well, but on the SC there is a groove running across the threads in the burr carrier which prevents an effective seal - grounds get shot out up from under the adjustment collar and not as much out the throat... oh well!

Or another source of air less plunger like:
http://www.amazon.com/Uniflame-Hardwood ... 003DPX5WE/

The possibilities are endless! I'm still unsure the direction I plan to go...