I recently got a Mypressi Twist and Kyocera grinder (my first espresso equipment). I've been using SM Monkey Espresso between 3 and 7 days after roast. I've tried updosing, downdosing (leftdosing, rightdosing), stirring the grounds, paying closer attention to my tamp, paying even closer attention to my tamp, and grind settings everywhere between 10 second gushers and choking the machine. I still get major channeling on almost every shot I pull. Any ideas on how to stop this?

Are you sure your grinder's good for espresso? I don't know much about the Kyocera hand grinders, but I do know that just because a grinder can grind fine enough to choke a machine doesn't mean it can produce a grind consistent enough to brew quality espresso. I had a real easy time with the Mypressi using a Baratza Vario and my K10WBC. If you're sure you're distributing the grinds evenly in the basket and you get disasters at every dose/grind setting, I'd guess your grinder is either not good or damaged in some way.

Edit: Also, are you roasting that SM coffee or getting it roasted from Tom? If the former, I'd suggest getting some professionally roasted coffee from one of our favorite roasters. It's good to make sure it's not a roasting problem.

It could be a problem with the grinder. I've heard good things about the Kyocera, but the grounds look inconsistent to me (although I have no frame of reference here). I might try it with a tested grinder if I get the chance. But could an inconstant grind (within the bounds of reason) cause channeling, specifically? I have the same question about roasting. I've been roasting the coffee myself in an iRoast2. It's possible that I'm roasting a little bit on the light side, and it looks to me to be a bit uneven. Overall, though, I think my roasts are in the ballpark. I know that this might not result in coffee that tastes as good as it would be if it were roasted professionally, but would it cause channeling?

I don't mean to sound thick-headed. I really am at a loss for what's going on here. I appreciate any help you can give.

Easy to rule out roasting issues by getting some from a well known joint that people love around here though... Super easy, and cheap, to rule out one huge variable I would think.

hypersoar wrote:..and grind settings everywhere between 10 second gushers and choking the machine. I still get major channeling on almost every shot I pull. Any ideas on how to stop this?

If you can choke your machine and achieve a variety of pour times (channeling or not), your grinder is most likely not the issue. You said that your coffee is fresh, so that leaves the distribution/tamp as the most likely cause. And while it's possible to screw up the tamp per se, it's almost always the distribution step that leads to channeling.

Do some reading or watch some videos of different distribution techniques e.g. Stockfleth, WDT and practice. If you take the pour spout base off of the Mypressi that makes it equivalent to a bottomless portafilter and the visual feedback will help you improve faster. My favourite technique is the nutating tamp, which is arguably the easiest tamp to master. This is also one tamping technique that effectively distributes during the tamp, so that you don't have to master a separate distribution step.

If you're still uncertain about the grinder, have a nearby coffee shop grind a small amount of fresh beans medium-fine (relatively coarse espresso grind). Then go straight home and try pulling a shot or two. If you still get channeling, it's almost certainly a distribution issue, not the grinder.

One issue is that the grounds don't come close to filling the basket. I've had somewhat better luck with dosing 15 grams, but it takes almost 20 to fill it up. I've been doing WDT sans yogurt cup (which I haven't found necessary to contain the grounds), but the other distribution techniques I see seem to require a full basket.

I haven't used a Kyocera, but I do have a Mypressi which pulls great shots with the basket half full or filled (before tamping). The basket does not have to be full & in fact most shots will pour and taste better with a dose closer to 15g. Try the nutating tamp method & 15g and I bet that your problems will resolve themselves in short order.

The nutating tamp does not require a full basket. With other tamps, an outstretched finger or curved piece of plastic are two approaches to distributing grounds below the basket rim. Trust me, at least to start the nutating tamp will be easiest for you to master. Once you are getting great shots, you can go back to WDT if you think that it makes for better shots or is easier to use at that point.

edit: I'm assuming that you are using the non-pressurized Mypressi basket. If you are using a basket that is stamped "coarse" (pressurized basket) or "pod", you should point that out to us.