Hi.
I have bought a new Hey Cafe HC-600 (A Mazzer SJ clone) and it's clumping a lot, even thought it has a doser.
I've read that apparently it takes some time for the new burrs to "burn-in", but I have also read that the static screen on the exit chute might be causing this.
Could anyone elaborate on why the grinder is producing clumps?

If it has a static screen, I would say that is the issue. Try removing it and see if this resolves the problem.

Isn't the purpose of a static screen reducing clumping caused by static electricity? If so, how come it is what causing clumping in the first place.

I'll try removing it, thanks.

I have never used a grinder with a static screen but from what I have seen and understand is that the grinds get compacted behind the screen and pushed through like a meat grinder, if you can envision that. Static doesn't cause clumping. It just causes grinds to stick to everything else (doser walls, etc.), not itself. You notice pretty quick when you have a static issue (grinds flying every which way as if pulled by magnets), but I haven't had any trouble with this on my mazzer. If you take the screen off, you should be relatively clump free.

Understood. Thanks again.

Bezman wrote:Hi.
I have bought a new Hey Cafe HC-600 (A Mazzer SJ clone) and it's clumping a lot, even thought it has a doser.
I've read that apparently it takes some time for the new burrs to "burn-in", but I have also read that the static screen on the exit chute might be causing this.
Could anyone elaborate on why the grinder is producing clumps?

This is a timely question for me. I've been wondering the same thing about my Quamar M80E, the recent doserless model. I think I've put around 6 lbs through mine and there is still significant clumping. I haven't been using WDT and some shots extract evenly but sometimes not. In comparison my Le'Lit PL53 was completely clump free after only 1/2 pound or so through it, and I get consistently good shots with it.

Those static grates not only cause clumps (which by Dan's testing, don't affect quality) but they make it difficult to clear the exit chute. I removed mine a long time ago without issues. Try removing it and see if you can deal with the static.

I thought this was interesting read on the screen function... perhaps less of issue with doser:
http://www.espressovivace.com/schomerbl...g-systems/

I put mine back, and just cut a few wires, to prevent clumping but still slow down the flow a bit.

I started taking apart the static screen and apparently it's electrically grounded.
I don't want to play with electricity just yet, so I'll leave it as it.

I'll try the wire method, see if it works.