Gary, that is NOT what I wanted to hear! I just don't use any beans that you would call dark roast, that's not the style I like.

I'm more than a little unhappy that a commercial espresso grinder in this price range would effectively be unusable in a shop environment, let alone modest home use.

I was heading over to a friendly shop this afternoon to try running a lot more beans through with the hopper, at an acceptable espresso grind. But maybe I won't bother now. It sure sounds like I'm stuck running the grinder empty every time I turn it on, whether I'm single-dosing or not.

Please let me know if you do get your Doge checked out by a motor shop. I'm not inclined to put any more money into this grinder, more likely to move on to something else.

FWIW the motor shop option may not be expensive. I will let you know.

I took my grinder yesterday to Scotty's Electric Motor Repair, a great local family business going back 25 years, and I dealt with Dick, the owner of the shop. He checked it out every which way while I was there, trying different capacitors, inspecting the motor and so on. When he finished he said "I don't want to waste your money" and refused to charge me for his testing. Fortunately he's the next driveway over from Compass Coffee on St. John's Road, so I picked up some of Mike's delicious beans for Dick's wife, who loves coffee.

Dick concluded that the capacitor in the grinder is already very powerful. Even doubling up capacitors doesn't improve the torque. PMs to David reveal there have only been about 40 lbs. of coffee run through his burrs, and his grinder stalls like mine if beans are partly ground where the burrs meet. The issue is the motor, which may be built for European current and has insufficient horsepower here. He says you can't just replace a motor like this, and you can't increase torque by changing belts, because it isn't belt-driven. The motor may be specifically designed for this grinder, and it is very high quality. The only way he saw to increase the horsepower and torque is to increase the number of coils on the motor by removing the originals and rewinding, and that's not practical, because it's a $300-$400 task. This isn't a problem for me because I single dose. But I've passed along that feedback for the manufacturer.

Gary, did the motor expert say anything about running the grinder on European voltage with a voltage converter? An engineer friend of mine suggested the voltage could be the problem, though he didn't examine the grinder. I've never used a converter, and don't know whether it would be safe or require swapping out the US power cord.

Great to know that the components of the grinder are such high quality.

I've been using a new (to me) dosing routine in the meantime. I weigh out beans for as many shots as I plan to make immediately, plus an extra 1.5-2g to account for retention in the chute. I then dump it all in the hopper and grind it all at once into the doser. I tare the portafilter on the scale and dose directly into the portafilter by eye, then fine-tune using the scale. At the end of the session, I fully sweep out the chute and the doser to leave it clean for the next session. For me, it seems faster than trying to get out every last bit of coffee for each dose. Not quite what I was hoping to use the hopper for, but workable.

Good idea on the voltage converter. I didn't think to ask. But like you, I just grind what I'm going to use. If I had this in a cafe I'd try the converter route.

What voltage is the grinder rated at? Unless it is 200V - 220V, I'd suggest double checking with a motor expert before going the converter route.

Here is the label, doesn't say 220:

wkmok1 wrote:What voltage is the grinder rated at? Unless it is 200V - 220V, I'd suggest double checking with a motor expert before going the converter route.

Of course. I expect you might have to swap out some parts so it would meet European specs. But I doubt they have a different motor for different regions.The guys at the motor shop said there may be a difference between running at 50 hz and 60 hz. I don't know enough to speculate about their reasoning on this.

If I find myself needing to serve a lot of people I've got a very nice Super Jolly with a hopper as a backup.

I guess I should have paid more attention at Rotating Machines class in college .

For a given level of impedance, doubling the voltage quadruples the power dissipated. The motor is already 700W (note that 746W = 1 horsepower), plugging into a 240V converter is prob not a good idea. There must be something else going on. It's hard to imaging a 1HP motor stalling. Did the motor shop do some impedance measurements of the windings to see if it is ballpark of a 110V motor?

That's good information, but to answer more clearly, Winston, I would not plug this grinder into a converter without checking with the motor shop first and I would not recommend that anyone else do so. Dick did many tests and was obviously thoroughly thinking his way through the possibilities. I did not ask him what he was thinking.