KnowGood wrote:The only way I would believe any and/or all of this is if your sidewall of your tamper was angled and not straight.

Have you tried it?

Wait...
Does that mean that the rules are now that we actually have to have some personal experience and/or factual evidence before posting our opinion here?!?!

Wow... traffic is gonna go WAY down.

Yeah, I would miss my "thought experiments" (as I'm sure AndyS would). Seriously though, the only tamper I have with a clearly angled side is the TORR:


From HB Roadshow - Espresso Tamper Reviews

It would allow for greater unencumbered nutation action, but it hasn't been an issue for me since (a) the tampers I use aren't that tightly fitted, and (b) the nutation I employ is far less angular than suggested by the diagrams above, similar to Dave's video I posted earlier (without the tapping, of course).

Even if you nutate in a quite exaggerated manner, it works (on my setup). I assume it's because the thing that 'side seals' is not the pressing down the edges as you rotate (which, indeed, the action doesn't really do for that 'outer ring'), but because you make a dense-ish mound in the middle and then smash it down, which, if you tamp with 30 lbs of pressure or more, probably pushes things out sideways (more precisely, radially). But my explanation, however plausible or implausible it may be, is a complete waste of time compared to actually doing it. It's cheap and easy to try. It's not as cheap as thought experiments, though--I will concede that.

Actually, for this it appear doing is a lot easier than talking. Who knew that twirling a tamper handle in a circle could be so complicated?

For the theorists, I would not assume a perfectly straight basket wall nor tamper side edge. I would also not assume a 'tight' fitting tamper, mine isn't. I also noticed comments that the coffee is 'pushed towards the center'. Looks to me that coffee is simultaneously pushed towards the edge as well (equal and opposite reaction).

In my 'version' of 'nutation', which may actually be 'precession', I begin with a straight down tamp, then work along the edge with a gentle up and down motion applying light pressure along the edge of the coffee bed. The tamper is only tilted a few millimeters from perpendicular. I then finish with a firm straight down tamp.

While I can't explain the physics, I can say that after 3-4 months of mostly poor results, this one change in my technique (albeit a bit tedious) has improved the quality of my shots. If the technique had no merit, I would not have consistent success with it. I do.

I'm sure my approach is somewhat unique, but it works well for me, and may for others. Try it, you might like it.

Hi,

first of all do try it, before you say it's useless. It's dead easy to give it a go and you don't even have to change the settings of your grinder, it's only the tamping that's a bit different.

Second of all you nutate the tamper only slightly, not 45deg, not 30deg, just a small move from the vertical position. I've got a convex Torr tamper, the base is identical to the one shown on the photo by Dan above somewhere and the nutation simply makes the egde of the tamper touch the coffee puck edge at a 90deg angle. Think of it like placing the tamper on a flat hard surface and moving the handle slightly to the side so that the edge of the base touches the surface. That's all that I do with the tamper sitting on top of the puck. I believe (feel free to correct me here) that this changes the way the coffee is pressed near the edges. By nutating the tamper you put more (perhaps the same as in the centre is a better description) force on the perimeter, thus 'sealing' the edges better. It looks like using a convex tamper doesn't provide the same compression of the puck on the sides as in the centre. I've tried moving the coffee around the basket, to create a concave surface and then tamp that with a convex tamper and I was still getting donut extractions. Just to note I was getting donut extractions on the Synesso as well, but the extractions carried on without too much problems, no squirts or sprites, just an uneven flow. I'm guessing it has to do something with the low water debit on that machine, but of course I might be wrong.

The best part is that you can do this with a heap in the middle of the basket (at least in my case) which means I do nothing more than nutating, no WDT, no additional re-distribution.

Regards,
dsc.

Without stirring anything up, I just wanted to say thanks.

[Nothing well documented or carefully tested below]

For quite a while I've been weighing, stirring and stockflething,

I've tried various other things, the pours never looked as consistently even.

I know, it's the taste, and I've had some good tasting ugly pours, but I figure a nice looking pour (coffee coming out evenly across the bottom of the basket) is more likely to reflect even distribution, and is my best chance at consistent good shots : nothing worked as well as all the fussing...

For about a week I've been nutating : dose straight into the basket in a heap, sit the tamper on top a bit, make a couple of circles with the handle, then tamp. I actually tamp, spin the tamper and tamp again - it cleans off the loose grounds and the tamper, and doesn't seem to hurt anything.

It worked the first time, has has worked pretty well every time.

I am using an 18 G ridgeless and pretty easy coffee (Klatch House and Joe from Ecco), 20 and one 21g weighing before I grind, cleaning the throat before dosing, so maybe not the toughest test.

I'll try some SO beans this week, and maybe a smaller basket.

So far I feel no need to return to the cut down pudding container and paper clips and I am glad.

[Alexia and SJ]

Thanks.

HB wrote:Have you tried it?

Every morning, but it isn't for sealing as much as it is for centering.

shadowfax wrote: if you tamp with 30 lbs of pressure or more, probably pushes things out sideways (more precisely, radially).

FWIW, working fine for me at somewhere between five and eight lbs, I'm guessing - I'm just using my fingertips to pull the tamper down firmly and using my fingers to ensure level with the basket edge.

grinding finer, tamping lighter.