EM440 inconsistent grinding on the same setting.

[samboy2k]

I been getting very inconsistent grinding on same setting on my em440. Not sure if other em0480/em440 owners have the same issue.

Equipment: Em440 with two shims installed (grinder 3 months old), EM6910

1. I vacuum and brush the insides for a thorough clean of the grinder
2. Put grinder back together, load beans in the hopper.
3. I grind coarse around 17-18, testing out the shot, its gushing.
4. Move the setting to 14-15, shot comes out good.
5. Minutes later grind again on the same setting , EM6910 chokes. ( I noticed the grinding this time, come out in clumps and grinds very slow)
6. I moved the setting back up a few notches 16-17, it still chokes.


I been wasting alot of beans and taking alot of time to make my coffee each time, grinding and pulling shot, moved grinders settings up and down. it just can'ts seem to stay at one grind setting. It is really frustrating, Any tips or suggestions ?

Thank

Sam

[LeroyC]

Yeah I had a similar experience with an EM0480. I bought it 2nd hand and it wasn't grinding fine enough for espresso so I thought it needed another shim or two. When I took it apart I found it already had 5 shims. I added one anyway which actually made it worse. So I went back to one shim and slowly added one at a time testing between each shim to see what the grind was like. I ended up back at 5 shims, but it still seemed to take a few days for it to 'bed in' so to speak. It might be worth doing something similar yourself, but you need to expect to burn through some beans in the process so maybe grab something cheap from Woolies.

[readeral]

I use one of these grinders daily. Are you purging the grinder after each grind change? It can hold up to 5 grams in it in my experience (especially if clumping.) This will still happen if single dosing, while running empty, knock your palm on the top of the grinder hopper. Surprising amount according to its size. If you're not purging, what could be happening is that your second bed of coffee has a mix of the two grinds and is appearing to be a good shot, but once the coarse stuff has been used, it's all now too fine. I usually find that changing by 1 notch is a large change, so if you're starting on 17, only move to 16 and purge the grinder then have another go.
Coming out in clumps and grinding slow may mean that the grinder is backing up somehow. I only do this when I hold my portafilter so close to the spout the grinds can't drop freely, so not sure what's happening there unless this is your approach too. Could be another issue causing this. As an experiment, try to run the grinder for one continuous period, avoiding stopping and starting and see if that helps. Overdose and take some grinds off if you have to afterward.

Other things to consider is how recently you vacuumed it out and knocked off caked on grinds.

Also what is true for other grinders is true for this one, it will grind far more consistently with bean hopper full (or partially) than single dosing.

[readeral]

Also consider your beans. Could be especially dry, too many fines produced etc.
Pull the thing apart, brush (as best you can), vacuum it out, try some different beans and change the grind setting minimally after purging a little each time. You can do "micro metric" changes with this grinder if you like by holding in the button at the back and twisting really gently.

[readeral]

I see you have another thread about adding shims. Did you do this? Was it grinding consistently (if still not fine enough) before then? Each grinder is different but I'll grind for espresso on an 8. This grinder normally can range from "Turkish" to "filter" (arguments aside about whether it's successful or not) so starting toward the middle of the range for espresso would normally work. However, if you've added extra shims, and it may not have needed them, it may be causing you the trouble.

That being said my grinder has 5 shims, but they were almost imperceptibly thin, 3 stuck together and I only knew there was five when the split just before I put it back together. Sunbeam may have put in less but thicker shims since my build (2009).

[samboy2k]

Thanks Rederals for your posts, alot of helpful information.

- Grinder was bought in October 2015 brand new.
- Was grinding quite consistently with medium style roast - Cafe Aurora brand from the supermarket, got decent 25 sec pours. Was on grind setting 1 or 2.
- Added some one shim to the grinder, only had one shim in the machine from factory, so now it got two.
- Thought tried something bit more fancy - Vittoria Mountain Grown. This is when things gone weird, alot of grind settings surfing to get it right, then when I grind again on this same setting, it the grinder chokes and grinds in clumps.
- Then I tried some new batch of beans Harris Columbian, same issue as above with Vittoria beans.

- With two shims the range of setting is around the 13 - 16 mark, with gushing and chokes inconsistently.
- With regards to cleanliness, I been cleaning it very meticulously with brush and vacuum.
- Grinder is usually half full most of the time cos Sunbeam manual said more consistent grind with beans weights in the hopper.
- My gut feeling, it seems to have issues with darker oily beans. my uneducated guess.
- Further then adding the shim, does the nut have tightened very tight ? as I only have a adjustable spanner not a socket set. ~ I.e. very tight reduce lateral movement of the bottom burr when motor is spinning ?

[readeral]

I couldn't tell you about the tightness of the nut, I went finger tight then a bit more until the burr rotated with my tightening effort. I only had long nose pliers to work with. Where did you get the shim from, Sunbeam? You might be fine with it in.

I think beans are your biggest issue man, supermarket just ain't gonna cut it. Your oily bean hunch is right, if they're too old, too dark, too oily they'll thoroughly clump and back up the grinder. You want dry fluffy grinds.
Your best bet would be to visit a local cafe with locally roasted beans less than 2 weeks old. Best before on supermarket packs represents when the beans would likely go rancid, not when they're past their useful use. Vittoria and Harris will both fail to give you any sort of quality and consistency.

You might also be finding that because the beans are so old they'll gush because you haven't been able to produce a good tamped puck. Find some fresh beans, make sure you're dosing and tamping correctly and try again, then from there we can better troubleshoot with you.

[readeral]

I suspect that your cafe aurora was also too old, but not being as dark it wasn't too oily. You still need to grind finer the older beans get, however. With fresh beans, without the shim, I reckon 1 or 2 would be far too fine, and it'd be around a 6-7. With the shim, I couldn't tell you, but possibly around where you are, the 13-14 range, which is probably good.

[LeroyC]

Ahh, I see your problem. You're using supermarket bought beans. It's possible to get reasonable fresh beans from the supermarket if you dig through the whole shelf and find the freshest ones. But there's no way to know for sure, and I'd say some less than fresh beans is definitely a contributing factor. So if possible I'd find your nearest local roaster and buy 500g of their cafe blend and follow the processes Al outlined above. If you don't have a roaster nearby then order some fresh roasted beans from Beanbay or a site sponsor.
Other points to note - just because coffee at the supermarket has a fancier packet and name and a higher price doesn't mean it's better coffee. And finally, the nut that secures the lower burr doesn't have to be all that tight, just nip it up with a spanner until the burr starts to spin and it'll be fine. Good luck.

[LeroyC]

I suspect that your cafe aurora was also too old, but not being as dark it wasn't too oily. You still need to grind finer the older beans get, however. With fresh beans, without the shim, I reckon 1 or 2 would be far too fine, and it'd be around a 6-7. With the shim, I couldn't tell you, but possibly around where you are, the 13-14 range, which is probably good.

Snap. (Yep, what Al says).

[noidle22]

Cafe Aurora is without a doubt the worst coffee I have ever tasted. If you see a pack of it anywhere, on the supermarket shelf, in someone's house, in a cafe, just run.
Run away as fast as you can.

[samboy2k]

Tried conescutive shots after a good pour, on the same grinder settings and dose it chokes, then have to progressively move the settings up, i noticed there is leaks progressively as the machine get warmer, my newbie gut feeling it perhaps not the grinder fault, its the group seal/head losing pressure to push the water thru when head gets hotter.

[readeral]

Ok, we need more details:
- Have you got fresh beans yet?
- how do you measure your dose into the portafilter?
- Has the machine been thoroughly cleaned recently?

Using scales will be your most accurate way and would eliminate it as a factor.

Overdosing between shots will cause it to choke and possibly may be the cause of the leak IF the group head deal is dirty/not seated correctly.

[readeral]

EM440 inconsistent grinding on the same setting.

I don't have any experience with thermoblock machines so my helpfulness is becoming limited.
For every shot does the brew pressure gauge reach the same level? I don't really trust the gauges but it might help to know.
Any other factors that might change between your first shot and the subsequent shots?

[readeral]

Posting multiple different threads is making it hard to help you troubleshoot. Better to keep it all in the one thread if you're trying to solve related problems.