Display Digital Tamper - Page 2

#11: Post by **jpender** » December 4th, 2022, 1:35 pm

Pressino wrote:I hadn't thought about this before, but your point now makes me wonder if the "best" tamp is the one that maintains the uniformity of coffee density throughout the puck, i.e. with the same density at the top, middle, and bottom of the puck.

I think while most people would agree that radial uniformity across the puck is important the value of top to bottom uniformity is less clear. It's likely that WDT encourages vertical migration of different sized particles. And as the shot progresses further migration probably occurs. At least one person who has actively experimented with intentional unequal vertical distributions claims it improves the shots.

Stir, shake, tap, tamp. Who knows?

#12: Post by **Pressino** » December 5th, 2022, 11:49 am

I'm curious about the experiments with intentional unequal vertical distribution, which ought to help answer the question. What distributions did the experiments test? Top denser than bottom, vice versa, and/or other distributions? I get the idea that radial uniformity is beneficial, e.g. with regard to alleged extraction "defects" like "donut extraction," although I'm not sure that is a real defect other than cosmetic.

For the past couple of days I've been extracting espresso using a "minimal tamping," which involves grinding into a single dose cup, pouring the grinds into a portafilter with a dosing funnel to allow a good WDT w/o spilling coffee outside the PF, then just leveling with an adjustable wedge leveler set to NOT compress the coffee, then gently setting a 1.7mm puck screen on top, then extracting the shot while observing the naked extraction.

The shots have tasted fine and extracted with no visible defects. I haven't checked TDS, and as regards taste, all I can say for now is it's been at least as good as my previous good shots. One thing I did notice is that the progression rate of change of the extraction from first drops to coalescence into the central stream seemed more uniform.

I'm not at all sure that WDT encourages vertical migration of grounds so as to result in an uneven density distribution. It might depend on exactly how it's done. I imagine that it would tend to make the puck more uniform in both vertical and horizonal directions. And just to be more sure that it won't result in non-uniform density, you could perform the WDT in the dosing cup and pour the coffee into the portafilter.

December 5th, 2022, 5:09 pm

Thank you Randy for the appreciative comments.
I've read with interest both tamper reviews.
Sorry for the Smart-Tamp.
The Force Tamper is still alive.
I think this is still your preferred tamper.
Sorry for the question but this was not clear to me:
"Level is important but controlling it mechanically is of greater value when it comes to egonomices".
Can you explain it in a different way?

I appreciate your response

December 5th, 2022, 5:26 pm

Hi Jpender,
thank you for the electronics "cool"

For sure my objective was to be repetitive in controlling both levels and pressure of tamping.
And for me, it works greatly.
My coffee setup is not a high-end coffee system.
Probably, having control of the tamping pressure and knowing that, by the end of tamping, the level it's ok, gives me strong and effective results.
"But wouldn't a scale provide the same thing without need for a specialized tool?" what does you mean with SCALE?

"The tamper weight itself is part of the force but it appears that your tamper zeros without including that. Some people just set the tamper on the grounds and call it good." Thank you for the suggestion: seems I have to pre-calibrate the weight considering the Tamper

Sounds good

"There is some evidence that tamping can be cumulative. That is, if you tamp and then tamp again it makes a difference in the density of the puck versus just the first tamp. So it may be the case that duration of tamp matters as well as maximum pressure." Can be an idea to measure the time spent to reach a tamping pressure target?

#15: Post by **ira** » December 5th, 2022, 5:27 pm

With your tamper it's imperative that the user pay close attention to what's going one, with any of the leveling tampers, you hold the ring against the basket and press insuring level with no effort. And with the Force or other pressure measuring tampers, you also don't worry about pressure, it's the same every time with no thought and no batteries.

December 5th, 2022, 5:31 pm

Pressino wrote:
Anyhow, AssafL's comment suggests to me that the "best" tamp is one that involves starting with evenly distributed coffee (WDT helps greatly there) and the gentlest leveling and tamping with the least pressure and "trauma" to the puck.

If indeed a perfectly homogeneous puck is the ideal. Food for thought?

Food! Food!

Let's imagine how to automatically distribute coffee and then, gently levelling and tamping.

#17: Post by **jpender** » December 6th, 2022, 2:25 pm

Mancio76 wrote:what does you mean with SCALE?

A digital or mechanical scale or balance that can read up to at least 30lbs/15kg. Put the portafilter on the scale and then tamp.

#18: Post by **Pressino** » December 7th, 2022, 11:43 am

After using the "no tamp" technique I discussed above for a few days, I found that some tamping is absolutely necessary for extraction on an e61 machine. It turns out my successful shots were dependent on my wedge leveler being adjusted so that it supplied a degree of compression in forming the puck. When I adjusted it to provide mere leveling without compression, the extractions were too fast and irregular. I'm working on finding the minimal pressure required to achieve a good extractive flow rate for the dose weight and grind level I'm using.

I still think there may be something to the idea that a uniform (top to bottom) puck density is a good thing, but it's also clear that coffee ground in my grinders and prepped in my usual way requires some degree of compression to extract properly. I'm not sure that can be achieved without unevenness