Post By Dimal
Post By artman
Post By DesigningByCoffee
Post By Yelta
Post By samuellaw178
Post By simonsk8r
Potential (ie most likely!) burr change
Heya guys! My shots have been very inconsistent over the last little while (grinder is a Compak K3 Adv Touch), I've gone through quite a list of potential reasons (always keeping in mind not to blame my tools hehe), but no matter how I distributed and tamped it just wouldn't be consistent.
Here was my list:
-Hopper actually needs screwing in (and it's affecting grinding if loose. YES I considered this as an option as ridiculous as it sounds haha, I never screwed my grinder in but just popped it on. Tried screwing in, didn't make a difference)
-shower screen needs cleaning (took off, and it actually looked pretty good. There was only a little buildup of old grinds but I let it soak in backflush solution and cleaned it properly, didn't fix the issue.)
-need a different more forgiving basket (I've always used my Pesado/IMS basket. If this was finicky like some people find VSTs I thought a change in basket would solve that. Got some EP Precision baskets and it didn't solve it)
-my distribution technique needs altering (went through the gamut of techniques, from super duper simple to complicated. Didn't solve it)
-Clean grinder or new burrs
-Something machine pressure related
I list these mainly to help others with any troubleshooting they can do if they find an issue.
I've already ordered new burrs for it, and I've just removed the top burr and was going to just clean it, but looking at the burrs I'd love if you guys could take a look and see if they look chipped. In a few photos it does look like it, and just wondering if I should just change to new ones. And it would be good to know in the pics things that are clear signs that they are worn/chipped (I've done the fingernail test and it does shave off nail still, but am concerned about the chipping).
I am the third owner of this grinder so I was thinking of just changing them anyway.
That is... if I can get this darn lower burr off haha! It is so screwed in I'm having difficulty if anyone has any advice. I've wedged it in so the burr won't move, and applied alot of downward pressure as I try to unscrew, but it won't budge. The top burrs screw out easily.
Thanks so much all, pics below (warning.... lots of pics haha. First two are of top burrs)
Last edited by simonsk8r; 13th April 2018 at 09:26 AM.
Probably need to remove the Burr Carrier and then use an Impact Driver to get the screw loosened.
Need to make sure though, that the screws don't use a LH thread, in which case you'll have to turn clockwise to loosen...
I wouldnt worry about the chips in the coarser (inner) areas of the burrs, that is not critical.
In the grinders I have played with the screws securing the burrs to the carrier have been normal (non LH thread), the shaft nuts holding the carrier have been LH thread.
The screws holding the burrs look to be posi not phillips, use the right bit to minimise chance of stripping the head etc.
As Mal said, if you take off the burr carrier (undo shaft nut - LH thread generally) it will be much easier.
I agree about ignoring the chips . But I found, like you, that grind inconsistency was the clue that my M4 grinder was ready for a burr change. I went from tiny adjustments required to huge swings with little change etc …
You might not see much in a photo, but if you run your finger nail over the burrs, you should be able to feel substantial resistance if they're still sharp – as the bluntening is really at a microscopic level. But if you're the third owner, then it may be time anyway.
Thanks heaps guys, really appreciate it. Yeah I have heard that about the chipping in the coarse/inner area not being that important. There are a few chips higher up past the halfway point, so was concerned about that.
And yeah the consistency is just bugging me.. But it wasn't even from a grind change. Grind would stay the same, but shot to shot would vary so much that it was just odd...
I actually wouldn't think the burrs would need changing going by the recommendation of when to change them, but it is about 4 years old and I don't know how the first owner used it. I might just change them and see what happens, no harm I guess.
Or beg/borrow/steal another grinder and see if it makes a difference first
Originally Posted by simonsk8r
Hmm that's an idea. I do have my old Rocky grinder somewhere that I was going to sell, but might be worth a go. I'll change the burrs first, if that doesn't resolve it I'll whip it out, then it'll show that it's either a machine issue or a 'me' issue.
Originally Posted by saeco_user
(I know, usually people do it the other way around, but I figure it's a third-hand grinder with chips already in it, may as well change them over to get a fresh start. Plus, I'm a bit over grinder troubles haha, as my previous one I had troubles with, so am going the shortcut route)
Cheers for the suggestion
Okay, I've had the burrs changed! Bought a kilo of the old Aldi beans just to run through if this seasoning of the burrs thing does indeed exist.
So I ran about half a kilo through all up then decided to pull some shots to see how they'd go.
..... quite varying results, so I ask you lovely folk for your thoughts if that's okay.
I've never had to change burrs and run new ones in (apart from my very first new grinder which lets be honest, I had no clue what I was doing then ). Are these varied results common behaviour from new burrs?
(I settled on a good dose that passed the 5c test, 20g was too much but 19.5g was perfect, also pulled shots prior to this and finally settled on a grind that was ballparkish, and made sure to purge a great deal before this new grind)
I kept all distribution and variables the same for each and every shot:
-19.5g y34.4g 28s
-19.5g y24g 35s
-19.5g y17.3g 35s
-19.5g y23g 35s
-19.5g y28.3g 35s
-19.5g y26g 35s
Seemed to start normal, slow down, then pick up again... And by the way each pour looked awesome through the naked, no spurts and a beautiful central cone with no dead spots (apart from the last shot which had minor dead spots).
So I guess I'm wondering what the plan of action next is:
1) Do you think maybe these results are moreso from the beans I was using? According to another thread, the Aldi beans are roasted 1 year and 3 months prior to the best before date. These are 28th June 2019, so roughly end of March they were roasted. So about 3 weeks old...
Should I disregard these beans (and the wacky results) and use my other freshly roasted (GOOD quality) beans I have to get a better gauge? (About 11 days postroast)
2) Or is it a matter of needing to purge more beans through to 'season' the burrs? Like I said, I'm unsure of the behaviour of the grind within the first kilo or so of beans, so perhaps it just needs a tad more through...
Thanks so much for any advice guys, appreciate it muchly
I think you're overthinking it all (but many may disagree)
You have nice new burrs now - results should be good.
Keep your consistent 19.5 dose weight (as you are doing - one variable at a time!).
Adjust the grind until you get a nice, 'drip that wants to pour' flow.
Pour until it starts to blond, and you're getting a good 25-40g double, how ever long it takes – and enjoy!
If it tastes a little bitter - go a fraction coaser and speed it up. Sour - tighten it up.
Don't stress the whole seasoning thing. I used some supermarket beans when I got the conical to get it into the zone – then just went with the flow. You may notice some variation that settles over time - but it's not much to worry about
Simon. You can’t honestly think 500g of coffee is enough to ‘run in’ new burrs. Can you?
All this talk of running in/seasoning burrs call it whatever you want, I've changed numerous sets of burrs over the years and never worried about running them in, it's a pointless exercise as far as I'm concerned.
I change the burrs, adjust the grind to my previous setting, maximum couple of shots I'm in the zone, then start pulling shots, sure over a week or two you may have to make minor adjustments, no big deal.
Why waste money/coffee, regardless of whether its cheap stuff or top shelf, not to mention needless wear and tear on the grinder.
Just another one of these pointless obsessive practices some of us seem driven to act out.
Thanks Matt appreciate it . I do have a tendency to overthink at times haha. I do wonder however what a normal variation is that people do experience from shot to shot? +1/-1 gram, +3/-3 grams? Hmmm.. I know it won't be spot on 100% consistent every time. Just wondering what others experience in their everyday well-tuned shots...
Originally Posted by DesigningByCoffee
Just unsure if 5g is a normal shot to shot variation...
See this is why I ask bud . I have read both sides: some say they absolutely do need seasoning, and some even say (with gusto) even up 3-5kg before you get consistency. Others say they have no need for it, they're good to go. It's hard reading contradictory info and making an informed well-educated decision sometimes, especially when the people I read from are people I truly respect and admire, and I always keep myself open to learning from them.
Originally Posted by LeroyC
But good call, 500g probs ain't much if they do need more time
Great, thanks Yelta appreciate it mate. That's sorta what I figured, but just getting clarification I guess. That makes sense, I'm sure it's a good idea to run a bit through, but not sure about the need for kilos of it... But I do ask as a genuine question, as I said before, both sides of the issue are confusing hehe.
Originally Posted by Yelta
Only thing is I put it back to roughly what my setting was before I changed them, run the grinder and just heard loud metal clashing! (They must have been a tad too close) Luckily it was only a microsecond before I stopped running it, but I hope I haven't messed up the burrs! The positioning must have changed and now am in a different arbitrary point number-wise (much "coarser", or perhaps the collar was just placed in a different position). But got it at a good espresso-fine level.
Man, on the occasions that I do weigh in and out, I get quite a bit of variation. As suggested above, cut the shot when it blonds and taste it. You don't taste 3g of extra/reduced output. You run the risk of letting metrics get in the way of making coffee that you like. Measuring certainly has its place (I do measure the dose I use....but as long as it's b/w 16g and 17g in my lever machine I let it ride).
Originally Posted by simonsk8r
Last edited by Barry O'Speedwagon; 18th April 2018 at 09:29 PM.
What machine are you using and do you have a way to check the brew pressure? It sounds like it might be machine-related, unless something is seriously wrong with the grinder (seems unlikely). The grind can be slightly less consistent with new burrs, but I don't believe it's THAT inconsistent...
I can assure you the beans will not be the source of inconsistency (taste is probably still up for debate).
In my opinion, the variance you're seeing is indeed bordering unacceptable. I tend to fix my brew ratio and then allow the flow time to vary. If all is well (machines and beans) and you have your techniques down tight, +/- 1 sec is not an unrealistic expectation in my experience (considering I start the timer manually). On casual days, I think +/- 2 sec should be more than easily achievable. Given that a typical espresso flow averages between 1-2.5 gram/sec, that translates to an expected variance of about +/- 5 gram max (less if you're pulling ristrettos and more if you're pulling lungos)...
p/s: can you post a video of the extraction?
Originally Posted by simonsk8r
Last edited by samuellaw178; 18th April 2018 at 09:44 PM.
Ah ok that's good to know. Yeah I'm definitely trying to not focus as much on the numbers nowadays, but just wondering what a normal variation is for others, as sometimes it does affect the taste if a shot all of sudden is running a bit faster than the previous one. Cheers for that Barry a good reminder.
Originally Posted by Barry O'Speedwagon
Am using a Profitec Pro 500, got it in June last year and it's been fine. But I'll make sure to check the pressure gauge next time to see if anything's happening there.
Originally Posted by samuellaw178
And ah whoops when I said "Seemed to start normal, slow down, then pick up again..." I didn't mean within the one shot, I meant the variations between the different shots. When the shot is being pulled it looks totally fine, starting off nice and droopy and comes together central, no crazy looking obvious pressure variations... But I can post a vid for sure, just not sure if it's a machine issue, grinder issue, a technique issue, or a completely normal nothing to worry about issue haha.
But if others commonly experience 5 gram max variation I'll sleep easier hehe.
Thanks so much for the input guys appreciate it muchly
Just been checking the brew pressure gauge for all my shots, and no troubles there, always ramps up to 9.5ish bars every single shot and stays stable there, so machine should be fine.
Pulled a few more shots this morning all on the same grind setting:
-20g y22g 32s
-20g y32g 30s
-20g y37g 30s
So quite a variation, but perhaps I'll just give it more time for the new burrs to 'settle' and find their proverbial groove?
Otherwise after a very good trialling if it's still showing such variation (and that it's not a user error which I will always keep in mind and refine my technique where I can), I'll just take it into someone to have a look.
For those tuning in, the shots since my last post have gotten so much more consistent, with very little variation. Thanks all, seems the burr change did something ;D very happy