I decided to try using a hopper instead of single dosing without a hopper. Grinder is Fiorenzato Doge Conico. Never had a jam previously, always adjust finer with grinder running.

I installed the hopper (not the huge stock hopper, but a short Macap M4/M5 hopper with a couple of gaskets to keep it in place) with the grinder already empty. Loosened the grind setting a little, then loaded the hopper. Pulsed the grinder a couple of times, then it jammed. Had to loosen the adjusting collar a lot before the grinder would run. Cleaned it out, made sure it was empty again, then reloaded the hopper pulsed several times for a few seconds, tightening the grind each time to get into the espresso range. Pulled a shot - way to fast. Ran grinder again and tightened a bit more. Turned on grinder again to load portafilter - jammed from start. Had to loosen grind a lot (again) to unjam.

Any idea what's going on? Already wasted a pound of George Howell Daterra South Italian trying to figure this out. Also don't want to damage the grinder.

EDIT: I did see previous posts about grinders, including an older Doge, jamming with lighter roasts. However, my Doge is a newer 700w model, so I didn't think that would be an issue for me.

Have you tried using it with the OEM hopper?

I dont know, but I did look up a picture of the two hoppers. THe original hopper has a lip around the insert tube section on which the hopper sits firmly at the correct height.

Perhaps as the beans grind the Macap hopper is jiggled around and pushed down, seated slightly too far and deep into the grinder, causing somehow for a jam?

Seems like its probably due to the hopper anyway, maybe you can sand it down a little shorter, or put an additional o ring on the tube of the hopper insert for it to rest on and not get pushed down too deep?

cuppajoe: I haven't tried the OEM hopper (since it's so huge I don't want to use it), but I'm going to try to get a bunch of stale beans tomorrow so I can experiment more. Using the Macap hopper with the gaskets does narrow the opening a bit, but not enough to cause a problem as far as I can see.

day: I thought of that too, but the hopper is in there pretty solid with two gaskets. There's also a finger guard below the hopper, so there is no chance the hopper could get close to the burrs.

I emailed the vendor, and his only suggestions were that I'm either underdosing/grinding too fine or need new burrs. I've only put maybe 30-40 pounds of beans through, so I don't see how the burrs could be worn out. As for underdosing, I'm generally getting around 30g of espresso in 25-30 seconds with an 18g dose, which seems pretty typical to me.

I also ran a couple of doses of Grindz through it this afternoon, just in case there was any residue gumming things up. Though it looked pretty clean in there from what I could see. It isn't simple to remove the burr carrier and open up the grinding chamber, so I've never done it - the manufacturer definitely did not intend for users to open it up for cleaning.

By the way, single-dosing worked fine today, so the problem only seems to happen when starting the grinder with beans already in the grind path.

Start capacitor problems?

The motor hums when I flip the switch, but the inner burr won't spin until I loosen the grind out of the espresso range. Would the motor hum if there was a capacitor problem? And if the problem is capacitor-related, would fixing that give the grinder more torque at startup?

This definitely sounds like a capacitor problem. The hopper would not add any strain to motor or grind path. It might be purely coincidental that you added the hopper and this problem arose.

Until I started using a hopper, the grinder was never starting with beans (or bean fragments) already in the grind path. So there could have been a capacitor problem since I bought the grinder and I wouldn't have known it.

The suggestion for using the original hopper was for testing purposes only, there may be something in the grinder/hopper interface causing problems. If the original one works well, then you could drill down on the differences between the two. If it also causes the problem, then there's something going on with the grinder itself.

As a tech I tend to start with simplest things first.

I have the same grinder and the same issue. There's not enough torque at startup to overcome partly ground beans nestled into the burrs. I don't believe the start capacitor has enough oomph. But it's not like you can simply switch out the capacitor and hope for the best. When I have time I'm going to take mine to a local motor company and have them determine whether I can upgrade the capacitor only or whether I need to swap out the motor to match the new capacitor. For now I grind enough doses for my morning coffee and leave the hopper off. It would be different if I were using dark roasted beans, which are softer, but I'm not. BTW I tried it with far less bean weight than in the OEM hopper and even a small amount of retained beans can jam.