There are lots of grinders that can grind coffee enough to "Choke" the PF, ..but ,..they wont all be able to grind coffee for a "good" espresso. I have choked my m/c using coffee ground in my wifes "spice grinder", ( yes desperate men take desperate measures in times of crisis !)..... but dispite many attempts, i was never able to make a half decent shot using it , nor indeed when trying a cheap electric burr grinder ! God knows its hard enough on a modern grinder with stepless adjustment and precision internals, never mind a hand grinder with old cast burrs in "sloppy" support bearings ! From your link...
Can the Spongs grind espresso? Definitely. They seem to do it differently than the European mills. The latter have more or less hardened, sharp, precision burrs and bearings and resemble the burrs in prosumer electric coffee grinders. The Spongs are a joke precision-wise. They have slop. There are two bearing surfaces, one at the back which is not captured and the shaft in the front. Both have a lot of play. I couldn't resist modifying one with a captured back bearing and I made it precise! Was it better? NO! I had to undo the modification. The built in slop is necessary because the two burrs don't precisely mesh in the first place. The burrs, unlike the European are cast, not machined and are similar to the American mills. They are not precision castings. They are in fact, quite sloppy. But they work.
Im sure you are having a lot of fun with that beautiful Spong, but at your stage with a new espresso machine, i think i would be trying to eliminate any unknown variables ,...and stick with a proven grinder set up. more power to your elbow ! ;D
