Replies to This Discussion

Permalink Reply by Mike McGinness on October 5, 2009 at 3:33pm

Doesn't really matter whether 20, 30, 50 or zero pounds. The tamps purpose is to preserve the distribution and is the least important of building a shot. What is important is consistency in the pressure you use. Individually and as a shop.

• ▶ Reply

Permalink Reply by Daniel Williamson on October 5, 2009 at 4:02pm

I kind of agree with mike here. Consistency is the key. Basically, when you tamp you are trying to create an even, polished surface on the puck. You are going to be hitting the coffee with 8-9 bars pressure which translates to 120-130 pounds of pressure per square inch. It's not really possible or advisable to try to tamp that hard (let alone the fact that as water comes into contact with the puck, it expands it). The primary concern should be taken on evenly dosing and and distributing the coffee. It needs to be evenly distributed and then the tamping should be level. The idea is that you are evenly distributing the grounds so the water can't have an easy pathway. The water will go where it is easiest to flow, and the coffee that is in that area will be over-extracted while the rest of the puck is under-extracted...obviously not the goal. So tamp pressure needs to be consistent from shot to shot because otherwise you have to change the grind. That is why so much time is spent in training on the tamp, even though it is a relatively minor factor.

• ▶ Reply

Permalink Reply by Liza on October 5, 2009 at 5:43pm

Totally agree with that, though I suggest to the people I train 20-30 pounds since anything more than that can be really harmful to your wrist. Again, the idea of creating an even bed of espresso is the most important and as long as you have an even and consistent tamp, you should be set!

• ▶ Reply

Permalink Reply by Daniel Williamson on October 5, 2009 at 10:46pm

Agreed. I tamp at 30 pounds. Channeling comes for a variety of reasons, though, and tamp pressure may not necessarily be the issue. For instance, tapping the portafilter too hard causes channeling. Excellent point to make, though, regarding differences in machines (particularly water flow).

Ricky Sutton said:

I agree with Mike, Daniel and Liza but with a stipulation.

I do believe that you can tamp too hard or too lightly.

I did a lot of experimenting with tamp pressure before i settled on 40lbs and incorporated that into my training. I varied my pressure and adjusted the grind to compensate tamping to everywhere between 20lbs and 60lbs. 20lbs always produced channeling. Every time. No matter the grind/dose/pressure/temp. Up to 30lbs and that disappeared, but as my machine has very little in the way of flow restrictors, the basket was still beading up more quickly than i desired. 60lbs and i had dead spots. Every time. I believe that pressure that hard has a way of intensifying the effects if your grinder has any sign of clumping issues. 40lbs was dead on with slow even saturation, no channeling and no dead spots. I have no doubt that this will vary from machine to machine depending on boiler pressure, flow rate, temp etc.

But as everyone else said, pick a pressure and stick with it. Train everyone on a kitchen scale and pull it back out once per month or so. As a new employee grows stronger, 40lbs will seem lighter and lighter to them.

• ▶ Reply

Permalink Reply by Daniel Williamson on October 5, 2009 at 10:47pm

By the by, what machine are you guys using? I'm on a semi-auto linea (no PID yet :-(

• ▶ Reply

Permalink Reply by Dawn E Donson on October 6, 2009 at 2:00am

Thanks, I knew we needed to be consistent so that the shot extraction would be consistent with each barista once the the grind was set. We are using a semi automatic nouva simonelli, which times your shot according to your grind and pressure on tamp is timed to the machine. When Gary tamps at 40 to 50 pressure and I tamped right after him at 30 pounds of pressure of course our shot times were very different. My shot ran for 46 seconds and his ran around 23 to 24. The espresso we are using is best really between 20 and 24.
Daniel Williamson said:

By the by, what machine are you guys using? I'm on a semi-auto linea (no PID yet :-(

• ▶ Reply

Permalink Reply by Dawn E Donson on October 6, 2009 at 2:04am

Yes, I like the 30 pounds because it is easier on the barista's wrist. I think we definitely would be more consistent with the 30lbs of pressure and we get a better extraction for our espresso shot. Thanks for your experience in our debate. dawn

Liza said:

Totally agree with that, though I suggest to the people I train 20-30 pounds since anything more than that can be really harmful to your wrist. Again, the idea of creating an even bed of espresso is the most important and as long as you have an even and consistent tamp, you should be set!

• ▶ Reply

Permalink Reply by Damon Lurie on October 6, 2009 at 2:04am

i was trained to tamp with about 15lbs of presure but it really is all rellative to how course or fine your ground coffee is

• ▶ Reply

Permalink Reply by Dawn E Donson on October 6, 2009 at 2:14am

Thanks Ricky for your advise, it really helped having input on this debate from way more experienced barista's than ourselves. This whole debate happened because all along I have been tamping at 30lbs and making really good drinks and then Gary who hadn't been on the machine and based his pressure on the Coffee Fest Barista book used the 40lb to 50lbs, then I pulled a shot right after him and my shot took 46 seconds to his 22seconds. So, definitely we need to be the same on tamping and 30lbs seemed to be good for most individuals and the wear and tear on the wrists. Though I agree consistancy...consistancy absolute and we must agree on that. Everyones input has helped us. We are very thankful for this website and for those who respond. Thanks again , and I will see this morning what 40lbs feels like.

Ricky Sutton said:

I agree with Mike, Daniel and Liza but with a stipulation.

I do believe that you can tamp too hard or too lightly.

I did a lot of experimenting with tamp pressure before i settled on 40lbs and incorporated that into my training. I varied my pressure and adjusted the grind to compensate tamping to everywhere between 20lbs and 60lbs. 20lbs always produced channeling. Every time. No matter the grind/dose/pressure/temp. Up to 30lbs and that disappeared, but as my machine has very little in the way of flow restrictors, the basket was still beading up more quickly than i desired. 60lbs and i had dead spots. Every time. I believe that pressure that hard has a way of intensifying the effects if your grinder has any sign of clumping issues. 40lbs was dead on with slow even saturation, no channeling and no dead spots. I have no doubt that this will vary from machine to machine depending on boiler pressure, flow rate, temp etc.

But as everyone else said, pick a pressure and stick with it. Train everyone on a kitchen scale and pull it back out once per month or so. As a new employee grows stronger, 40lbs will seem lighter and lighter to them.

• ▶ Reply

Permalink Reply by Ron Ingber on October 6, 2009 at 5:01am

Maybe everyone (except me) knows this, but how do you determine what tamp pressure you are actually applying?

TIA

Ron, the Country Guy

• ▶ Reply

Permalink Reply by Bryan Wray on October 6, 2009 at 9:03am

Ron Ingber said:

Maybe everyone (except me) knows this, but how do you determine what tamp pressure you are actually applying?

TIA

Ron, the Country Guy

Pull out a bathroom scale. Find out what your average tamp pressure is by just doing what you already do, only on a scale. Muscle memory will lead from there.

As already mentioned numerous times, whatever pressure you apply the key is that the pressure remain consistent from shot to shot. If you tamp with 50 pounds so be it, but keep that variable in check. 20 pounds? Same deal.

-bry

• ▶ Reply

Permalink Reply by Fraser Jamieson on October 6, 2009 at 9:04am

You can use a bathroom scale, for example. However, remember that as you change the counter height, your body mechanics will change. Keep that in mind, but you should be able to learn how your favourite pressure feels.

Ron Ingber said:

Maybe everyone (except me) knows this, but how do you determine what tamp pressure you are actually applying?

TIA

Ron, the Country Guy

• ▶ Reply

▶ Reply to Discussion

• ‹ Previous
• 1
• 2
• 3
• Next ›
• Page