Hi all,
I have a new Profitec T64 grinder, traded in a Baratza Sette (that's a longer story). I am having trouble achieving consistency with this grinder. I get it dialed in, come back in the morning or even later that day, and get a very different result from the same full hopper of beans. Not a little tweak but a significant difference. Last night dialed to get 19.5g, yielding 36g at 27 sec. (pretty good shot). This morning, with no change in grind setting, 19.5g yielded 36g in 41 seconds!! At least two turns of the worm gear (2-3 notches) to get back closer to the previous results. This has been happening since I got it a few weeks ago and it makes it impossible. My three previous grinders would stay be pretty consistent over the day, with minor adjustments as the beans age and conditions change...but minor adjustments. This goes from great to undrinkable with no change in setting.

The grinder retains grinds a little, so I purge before each use and after each grind adjustment. I am grinding by weight directly in to the portafilter on a stand on a scale. and weighing the cups as I pull the shot.

I am wasting a lot of coffee having to dial it in every time.

Does anyone have any suggestions?

Thanks

How much do you purge each time?

After you have it dialed in, does the immediately following two shots pull exactly the same?

I purge about 5g or so I would guess, I don't weigh it.
Repeating immediately during the dialing in process seems to yield expected results for repeated pulls, although I don't yet have the feel for how much impact to expect or each notch on the grinder.

Thanks for any insights.

I'm suspecting it wasn't purged enough. So the effect of grind change is delayed and is only seen 1-2 shot later. If you have dialed in the shot (say, 18g in 30g out in 30 sec), the next two shots should be very close (same in and out in 30 +/- 1 sec). Measure them all just in case any minor deviation/drifting is caught. If you did that and it passed the test, then maybe the grind adjustment mechanism or the burr carrier has some issue (but unlikely since your issue is time-related).

It makes sense that inadequate purging delays the effect of grind adjustment i.e. my last adjustment (tighter) was actually using some grinds from the previous setting, such that the actual tightness of the grind didn't show up until the subsequent shot or two. I will try purging more.

It feels like a lot of waste to have purge so much to clear the last grind.

I have read that the retention is high on this grinder. I wonder if I should consider removing the anti-static screen which appears to contribute greatly to the retention?

Thanks for your insights!

My Super Jolly E behaves exactly the same if I don't purge a significant amount. When I bought it new a few years ago I almost returned it thinking there was something wrong with the grinder.

I'm getting exactly the same with my new T64. Its driving me mad!

I'll experiment with purging without the temptation to tweak it.

Thanks

I hate that grinder from ECM.

If you purge insufficiently, the partially stale coffee makes the shot flow faster, not slower. Something else to consider: I don't know about climatic changes in your home environment, but If you have dialed in in the evening and pull a shot first thing next morning, then If the ambient temperature and/or humidity is lower, the shot will be slower. I experienced this because my grinder is standing close to a window and on chilly mornings it made quite a difference.

I've had the T64 for about a month now and have never seen this problem. I do purge about 8 or so grams before my first shot of the day, just to get rid of the stale grinds retained in the chamber from sitting overnight. That's the only purging I do. The rest of the day, I probably pull about 1 double an hour for a total of maybe 7 to 10 throughout the day. All my shots pull almost exactly the same, with some slight variances on particularly humid days, but even then it's maybe 3 to 5 seconds difference to get the same output. I did run about 4 pounds of some cheap coffee through it when I first got the grinder, to season the burrs (I have no idea if this is effectual or just bullsh**).

Grey