I am getting some shot/pour inconsistencies, the results of which change drastically simply by changing baskets - but I don't really understand why. Obviously my technique, but I am not sure what I am missing/doing to cause it. Hope someone can offer some advice. I'll give you two examples of the differences....
Equipment - Macap M4 grinder, Bricoletta Rotary (automated controls), La Marzocco PF, Pump (with static gauge measurement) @ 8.8 Bar, Reg Barber flat bottomed 58mm tamper.
Case 1 - Using the above equipment, but with a straight walled double basket...I get edge channeling and/or early blonding about 1 shot out of 4. As well, I usually get to just under 2oz before blonding starts (at 20-25seconds). With this basket (empty), the tamper can insert quite far into the basket before it meets resistance from the basket walls - i.e. I could potentially apply more pressure to the grounds - perhaps amplifying my mistakes in tamping or distribution? Tamping exactly 30lbs with no tapping, using finger to distribute in a Stockfleth like circular manner.
Case 2 - Using the above equipment, same distribution and tamping technique - but with a curve walled double basket. With this basket, I get very consistent, even shots (about 9/10 times), often exceeding 2-2.5oz and still running thick and rich into 30-35 seconds. This basket does not allow the tamper to drop as far into the basket as the straight walled basket from Case 1, and meets resistance from the basket walls early - i.e. it stops me from applying a full pressure to the grinds perhaps. I am bottoming out the tamper on the walls before I hit 30lbs on the grinds themselves.
Now, my own thoughts tell me that the basket that I can insert the tamper further into would have an improved tamp, greater puck consistency etc., but the opposite appears to be true. Does this make sense to anyone, or does this point to another problem elsewhere?
Grant
