[cpenner461]

I use a fairly fine grind, although not as fine as I use for espresso. According to the stock AeroPress instructions it should take about 20s to depress the plunger, if it's too hard to press it's too fine, and conversely if it presses with little to no resistance then it's too coarse.

[joezydeco]

I use a very fine grind (actually I cheat and use Cafe Bustelo right out of the bag). I've noticed using the inverted method makes the plunge step a lot easier, probably because the grounds are mostly still suspended in the water and not sitting on the filter right away.

[fieldforceapp]

20s with 'average' pressure... good guidance, thanks!