I added the three VST baskets: 15, 18 and 22. They have the same hole area. The measurement based on the punchout area diameter is misleading, since these baskets do have more holes, but smaller hole sizes.

You can see the measurement errors by comparing my VST 18 reading to that of Bob. (The two LM doubles are slightly different OEM versions and the numerical differences aren't due to errors)

Hi Chris: I'm actually fairly impressed by how close we were; I would have expected more variance, not less. The data are certainly close enough for making sensible dose and grind adjustments. It'll be interesting to see if the different hole parameters used on the VSTs catches on.

another_jim wrote:I want them all.

I'll try and measure up my La Peppina and Gaggia Factory baskets then.

another_jim wrote:How different is your lever from a regular machine in terms of grind requirements. Suppose you grind coffee for a good shot on your pump machine. Then you use the conversion based on hole area to load the equivalent dose/same grind into your lever basket. If the resulting shot is a gusher or a choke it tells you something about the lever group. The NS Athena (Astoria group) required an extra fine grind when using normal baskets, so the idea is not a stretch.

Since I'm running lever only as my regular machine, such a comparison is hard to make. My La Peppina and my Mypressi Twist are pretty close in grind, but the Gaggia Factory takes quite a bit finer grind. Oddly, when I was pulling side-by-side shots with Dr. Gary with his La Pavoni, the Gaggia Factory required a much finer grind then his La Pavoni which surprised me as the baskets should be the same.