Proper depth of coffee bed

Salvatore Taibi

I just read Reiss's excellent post on the angle where the lever grabs, and it matches exactly with my experience. My question, however, is if anyone has measured the depth the coffee bed should sit below the rim of the basket. I know about the "dime test"' but I would prefer a number. If you are using the OEM basket, obviously a visible reference is the line on the basket, but for anyone using a VST or IMS ridgeless basket, we don't have this reference point. Thanks!

Frans Goddijn

The 'dime test' is useful to make sure you do not damage the puck while locking in the portafilter.

Otherwise, once you are able to consistently make fine espresso using the stock basket, you can move to, for instance, a VST basket and if it is an 18g basket, load it with 18g of the same grind setting, and subsequently make very small and subtle changes to your grind setting or dose according to your taste and visual observations.

An exact figure in mm can not be provided because it depends on bean freshness and roast. A darker or fresher bean can work with a coarser roast and that dose will take up more space. A less fresh or a lighter roast will need to be ground finer and the same weight will then take up less space, also you might want to increase the dose to enhance the taste/mouthfeel.

Salvatore Taibi

Yes, Frans, but as Reiss states (and correctly, I believe) if using a darker roast you may grind 15.8g whereas with a lighter roast you may increase the dose to 17.3g. In my case, my normal dose is 14.5g with a dark roast (VST 15g basket), but when I decide to try a lighter roast, without even thinking I automatically know to increase the dose slightly to 15.5-16g and grind a touch finer. Either way, the headspace is remaining the same. We are altering the dose and grind to accomplish the same depth.

Perhaps I am way off the mark. I don't believe there is an awful lot of difference in grind weight, and it is why I believe a double and a single (or a triple) should taste very similar. I think we should lock in the weight based on basket (i.e., 15g =/- 1g for a VST 15g basket) and then go off dialing in the grind based on time and extraction. I know Matt Perger has recommended something similar, and I find this to be the easiest.

As for depth, my question goes straight to how much headspace is optimal for the machine to perform at its best. Maybe there is no answer...

Reiss Gunson

well i think the answer to that question is that that press line in the side of the stock basket must be visible.