# Center of mass - weighing espresso grind in portafilter with the handle on the table

I was recently watching someone weighing the grind of an espresso in a portafilter. Baristas have to measure the weight of the grind in order to know if the grinder is outputting the correct amount of coffee by the gram.

We use a pretty simple scale which measures by the gram and we can tare the initial weight to actually measure what we are weighing.

Because the portafilter is pretty big, a lot of people have the handle on the table with the main portion of the portafilter (the metal part) on the scale. For reference here is a picture and you can imagine the scale being only under the metal part.

Someone called out to me recently that because the handle is on the table, it wouldn't be good measure because the table is "supporting" the weight of whatever you add on the other side since the weight would get distributed. I see a lot of baristas do this so was curious how much of an impact is this really? My initial thought was that because we are taring the initial amount, that weight is accounted for? Also the support from the table happens on both sides I would think?

I imagine since most of the weight is on the portafilter side, perhaps it's negligible? Maybe I misunderstand the physics entirely.