The Scarce device isn't really required. I have a 5 foot long 36 gauge T junction teflon coated wire which fits neatly over the edge of the PF and into the basket space. For repeatability I suppose that it could be anchored but I haven't bothered.

The only problem with this set up is that you have a PF full of water which is thermodynamically different than one filled mostly with coffee. I have chosen to ignore the difference in my tests. My results on the La Spaziale are very similar to Greg's results on the La Marzocco.

Bob

bobroseman wrote:The Scarce device isn't really required. I have a 5 foot long 36 gauge T junction teflon coated wire which fits neatly over the edge of the PF and into the basket space. For repeatability I suppose that it could be anchored but I haven't bothered.

The only problem with this set up is that you have a PF full of water which is thermodynamically different than one filled mostly with coffee. I have chosen to ignore the difference in my tests. My results on the La Spaziale are very similar to Greg's results on the La Marzocco.

Bob

The test conditions are quite different between the two measurement methods. In your method how is water flow rate controlled? Several years ago, I made a bunch of measurements on Rancilio Silvias using T type thermocouples snaked up through the filter basket with the probe resting on top of the coffee cake. It was a ton of work and couldn't make constant duty cycle measurements. The thermofilter makes it almost trivial.

-Greg

gscace wrote:

bobroseman wrote:The Scarce device isn't really required. I have a 5 foot long 36 gauge T junction teflon coated wire which fits neatly over the edge of the PF and into the basket space. For repeatability I suppose that it could be anchored but I haven't bothered.

The only problem with this set up is that you have a PF full of water which is thermodynamically different than one filled mostly with coffee. I have chosen to ignore the difference in my tests. My results on the La Spaziale are very similar to Greg's results on the La Marzocco.

Bob

The test conditions are quite different between the two measurement methods. In your method how is water flow rate controlled? Several years ago, I made a bunch of measurements on Rancilio Silvias using T type thermocouples snaked up through the filter basket with the probe resting on top of the coffee cake. It was a ton of work and couldn't make constant duty cycle measurements. The thermofilter makes it almost trivial.

-Greg

Greg,

In the picture earlier in the thread you will see there is a needle valve which can be adjusted to permit 2 oz of water to flow in 25 seconds. The pressure can then be read.

However when it comes to measuring temperatures, my set up has problems. One is that the placement of the TC can vary and, two, there is no coffee in the basket and so the thermodynamics are wrong. As I stated, I have ignored these things. Your method might eliminate those problems.

When I said that your device wasn't required, I meant in conjnction with mine. I'm sure that your device works quite well as a stand alone.

Still, my curves are remarkably similar to those that you achieved on the La Marzocco, if memory serves.

Bob

bobroseman wrote:Still, my curves are remarkably similar to those that you achieved on the La Marzocco, if memory serves.

which means exactly nothing.

barry wrote:

bobroseman wrote:Still, my curves are remarkably similar to those that you achieved on the La Marzocco, if memory serves.

which means exactly nothing.

I am not comparing the La Marzocco Linea with my La Spaziale S1. Heavens no! I wouldn't presume. I intended to compare two temperature measurement approaches not two machines.


Greg's curve here:


reminded me of my curve here:


However, even at that, I am quick to point out that Greg has given this much more thought than I have. My humble contraption was intended to allow me to measure pressure. I quickly became discouraged in trying to measure temperatures. I took a lot of data but was able to come to no meaningful conclusions as a result.

Over and out.

Bob

bobroseman wrote:I am not comparing the La Marzocco Linea with my La Spaziale S1. Heavens no! I wouldn't presume. I intended to compare two temperature measurement approaches not two machines.

nothing wrong with comparing machines. my objection was the comparison of methods, followed by the comparison of machines, as if to say the similarity of curves validated your <admittedly flawed> method. comparing the curves means absolutely nothing, other than, perhaps, for us to say, "hey, look! curves!"

btw, http://www.angry-bunny.com is my site, not greg's. check out the madeleine pages for baby girl photos!

--barry "need to stop messing with espresso and update her pages"

barry wrote:

bobroseman wrote:I am not comparing the La Marzocco Linea with my La Spaziale S1. Heavens no! I wouldn't presume. I intended to compare two temperature measurement approaches not two machines.

nothing wrong with comparing machines. my objection was the comparison of methods, followed by the comparison of machines, as if to say the similarity of curves validated your <admittedly flawed> method. comparing the curves means absolutely nothing, other than, perhaps, for us to say, "hey, look! curves!"

btw, http://www.angry-bunny.com is my site, not greg's. check out the madeleine pages for baby girl photos!

--barry "need to stop messing with espresso and update her pages"

Yes, I see that it is your site. And a fine site it is, too.

Before pleading guilty to fuzzy headed thinking I went back and reread the description of the Scarce device. I see a lot of similarity. Both use T-junction probes, both restrict water flow and neither measures the actual temperature above a real coffee puck. ( The question of t-probe placement error between the two devices is addressed by the J probe (Banjo Bolt) comparison.) I also used a special insulator (a cut down sponge) but I can't claim that it mimics the thermodynamic characteristics of a coffee puck.

But even so, you can't compare measurements, both taken on uncalibrated instruments. So, I retract my statement. I am no longer struck by the similarity of the measurements. In fact I am somewhat bored by the similarity. I am reminded why I quit measuring temperature and ultimately resorted to actually drinking the outflow in order to set my temperatures.

Thanks for putting me right.

Bob

bobroseman wrote:ultimately resorted to actually drinking the outflow in order to set my temperatures.

DING DING DING! We have a winner!

barry wrote:

bobroseman wrote:ultimately resorted to actually drinking the outflow in order to set my temperatures.

DING DING DING! We have a winner!