Wietse wrote: Either way, it makes me wonder whether burr alignment isn't still another factor that may explain different experiences with different grinders, in spite of what others have commented on this topic. Has anyone else tried to adjust to almost zero on his grinder and heard burr rub before actually getting to zero (with the burr lock knob tightened!)?

I've mentioned this several times in various HG-One threads. You do need to check to see if your burrs are properly aligned. Mine weren't & it took shimming the gearcase to get them right so the grinder would produce a decent grind quality. I wouldn't consider any burr contact outside of the zero point acceptable. I also found that the shim stock that Paul & Craig sent was too thick (.040+) & ended up using some stock in the .020 range under several corners of the gearcase to properly set up the burrs.

You also want to make sure that the threads in the burr carrier & mount are well greased. This will significantly reduce the carrier movement when you retighten the locking knob.

True, you mentioned this John and I do recall reading your comments. However, I also remember that you noticed burr rub in the normal grinding range, correct? I assumed that what you described was a much clearer case of misalignment than what I was seeing (or rather hearing) in my grinder, especially now after a couple of weeks' use. Anyhow, I might reconsider having a look at it; I still have the shims Paul sent me lying around. I'm not sure though if I'd be able to improve alignment if the deviation is so minimal, but maybe I'm wrong and it's worth giving it a try. How hard did you find it to properly diagnose the exact misalignment and to fix it with shims?

PS: I intended to mention this in my first post but I really want to stress that Paul and Craig have been very helpful when I asked them about the possibility of misalignment. It's been said before, but their customer support is excellent. I just wanted to mention that.

Wietse wrote: However, I also remember that you noticed burr rub in the normal grinding range, correct?

I played with it several times but as I recall the actual contact was about 1/4 turn below my pump machine grinding range but the burr alignment is still off throughout the usable adjustment range. You won't get a nice uniform grind unless the inner burr is centered down close to zero. I had contact from 4:00-6:00 looking at the bottom of the burrs. You have to figure out what direction the inner burr needs to move & shim the gearcase accordingly.

With the carrier lock knob tight & the grinder upsidedown just use a 1" long piece of paper to check the alignment. Slip it up between the burrs & slide it around the circumference starting with the carrier adjusted a 1/4 turn tighter then your normal grind point. It should slide freely around with no binding until you've tightened the adjustment in 1/4 turn increments to the point that you can no longer slip the paper in between the burrs. Remember to retighten the lock knob after each adjustment.

For shims I ended up using strips I cut from a roll of the metal heat tape you find in hardware stores. This mic'd up around .020+ thick.

As I am coming up on 10 lbs, my extractions have improved quite a bit. They actually look pretty much perfect, except for some small spritzing. My spritzes are so small that I can't even really see them; I can just tell from the residue on the back of the machine. I'm not sure that effects the taste at all. I certainly can't tell.

My technique is pretty much the same as what I used with my old grinder. I grind into the tumbler, then drop into the portafilter with a dosing funnel, then quick WDT.

I am guessing that proper break in must have a significant effect. I have been so lucky hat i bought my lovingly cared for HG used and have had nothing but perfect extractions right from the start. I have serial #2 with the regular 83mm burrs. I grind directly into the blind tumbler and stir 2-3 times with a mini bar whisk. I dump directly into the portafilter and tamp without leveling or further distribution.

I say keep up with the break in and expect a major improvement. The TIn burrs probably require more work....

I don't know how you can evaluate taste without focusing on ratio.

Just on a side note:

It took me two months and over 12-15 pounds of beans to brake in my Mazzer Robour which has the 71mm burrs set. My guess is it may even take longer with a hand grinder.

This business about burrs alignment is something which is disapinting to me. One would think that this is a quality control issue that needs to be addressed before the units are shipped out.

Rob

damonbowe wrote:I don't know how you can evaluate taste without focusing on ratio.

I evaluate taste by taste, which is obviously subjective. Numbers are guidelines, nothing more.

I use to pull by the numbers when first starting out. After years of pulling shots you just know when things are going well.

I have the TiN's, never did any break in, just started making espresso... Things got better quickly, but I guess this was most likely due to finding the right technique. I've been using the HG-One for 2.5 months now, so that's approx 4 kilo's of coffee. I do notice grinding requires more force and less turns, but I have never run any cleaning tablets through, so maybe there's coffee oils sticking to the burrs making them less slippery so they're pulling in the beans better? Does that sound plausible?

Anyway, here's my method:
- with some RDT there's zero retention.
- catching grinds in Stephens acrylic funnel
- a few 'whisking' stirs with a mini cocktail whisk
- some soft 'thumps' with my middle finger on the side of the basket to settle the grinds, leaving a slightly flattened hill in the middle of my Strega VST single basket.
- a soft tamp
- ca. 10 grams, slightly touching screen, but really slightly
- bottomless PF
- 4 seconds low-pressure pre-infusion seems to help in closing any gaps

Consistent perfect centered shots. No spritzers.

The only time I get spritzers is if:
- grind was too coarse
- beans too old and dry
- pre-infusion pressure too high.
- of course, bad distribution

But even if I do everything right, using old dry beans gets me spritzers.
I home roast, so my beans are rarely older than 7 days, and the extractions are amazing.
Sometimes I buy a bag of melange, to try something new, and if they are old, there it goes: spritzers!

I'm sure you think: yet another anecdotal description of some dude's magic preparation, and you're right, this might not work for you. Like stated before, everybody will develop their own technique, suiting their dosing, basket design and espresso machine etc.
But it can be done and doesn't take too long to learn (and to do).
I think the HG-One is a very capable machine, if you have the patience to learn to use it.
And the big advantage is in the single dosage, zero retention, letting you switch between beans.
In the end, it's the taste that matters the most. And this is where the machine shines.