I prefer the 189 for any dark roast or medium roast which have no acidity. As I said in the review, the 200 burr creates a lot sweetness whenever there is acidity in the coffee; but falls flat when there is none. The 189 is a little cleaner and sweeter on roasty flavors, but doesn't give a nice rend...

It varies dramatically by grinder -- I've opened up the all the single dose grinders I've tested, swept out the loose grinds from burrs, grind chamber and chute, and got from a superlative 0.05 grams to a failing 1.5 grams. But that is for another topic, not here

I'm puzzled how burr rotations can predict grind weight unless the number of beans fed into the burr at each rotation remains equal. This would seem to require a highly constant weight of beans in the hopper. It seems a long way away from single dosing territory

Ramp/soak PID controllers are fairly inexpensive now, and using them on inlet temperature is a lot more robust in control terms than on bean (outlet) temperature, due to the faster feedback. The ramp/soak allows you to program separate ramp up and straight line times. You can also use several segmen...

It does. I run very similar bean temp profiles on my Quest drum and P1 air roaster. For the drum, I keep my environmental temp at roughtly 500F throughout. On the P1, I ramp up the inlet air temperature from 300F to 475F in the first seven minutes, and keep it steady for the last three. The final

I think your cut and paste fell into a time warp, and got tranlated in 1999

Here is a better translation:

I did molykote the timing belt, as suggested. It's been a quieter (more than a little bit, but not dramatic) when the motor speeds up for the purge; and it stayed that way for the past few weeks. Don't know if it's permanent, or if the lube will need to be repeated

I would like to comment on alignment before this thread goes off the rails. Per our own Jake-G, who rebuilds grinders and can do extensive testing, as well as high end grinder builders like Titus, simple tests at the zero point, like using a marker test or the gap betwen chirp and lock are not good ...

The video in the last entry shows how the grind adjustment works. There is a lock at the zero marking (as well as the 145 marking), so it is impossible to make more than one turn on the adjustment wheel. I removed the collar to check for the chirp, and it was approximately at -3. After I changed