Can you choke your machine with your grinder going below 7? You could try 3 or 5 see and then go coarser until you get the flow you are looking for. I wouldn't trust the manual as it might be for pressurised portafilters. I hope this helps.

 

Hi, thank you. However I am at setting 1 on the Wilfa and the shot is pulling like I described above at 17gr of coffee in to 50 ish gr out, at around 17 seconds. Going smaller doesn't seem to help, but then maybe bigger doses are clinging to the screen and channeling excessively? The story is about the same with the coffee-shop-ground coffee (maybe the flow is actually faster), which is why I find this so puzzling. I don't know if dosing higher will help and I cannot grind finer at this point.

I thought at this point it would be helpfull to describe my prep. I start with measuring around 17.5gr for 17gr dose (the wilfa usually has some retention), I then measure the ground coffee again to get an excact 17gr which I dose into the portafilter using the funnel, usually there is little to no clumping. I tamp hard enough I think(I've measured the pressure with a bathroom scale). right now the VST's lip is a little big so its hard to get the arm perpendicular to the machine but its about there. I then press the brew switch and after a few seconds its starts pouring out.

 

All right. Measured out 16gr, ground with the 1 setting on the Wilfa. Started the brew and immediately turned the steam wand to 11 for the first 5 seconds. Result: 48gr out after 12 seconds, shot tastes acidic and muddy. I'm going to do the same for the Coffee-shop grounds just to double check.

EDIT: still bad, also tried going up in grind-size in case too fine a grind size wouldn't choke but created areas of the puck where water couldn't flow and so it easily channeled to other areas. Results remain the same as above.

 

but I cannot seem to pull a decent shot because what seems like too fast flow, and I know I know there are countless posts about this on the internet and several here, its always about grind size and the amount of coffee.

This would point at your grind, and therefore the grinder being the shortcoming.

The thing is my grinder should have no problem grinding espresso sizes (Wilfa uniform),

Not from experience but I do see some reports that the Uniform does struggle to go fine enough.

At one point I even went to a serious coffee shop and purchased their espresso blend which I had them grind at the same size as they use for their machine (which isn't apples to apples here but with dosing should put me where I need?).

It might, but there's so much in the equation that it can't really be used as a measurement.

I must've drawn 40 or more shots trying to figure this out but no matter what dose, how hard I tamp or how fine I grind (I'm down to size 1 on the Wifa) the shots pull something like 50gr out from 17 gr of coffee in about 18 seconds. I have tried dosing up to 18gr but pulling the portafilter to check I find the coffee (pre-shot) iseems to stick to the shower screen above about 17.5gr and so I believe I've hit a dose ceiling here?

Tamping harder has very minimal effects (the 15bar or so that your machine delivers will soon sort that out!). I'm not sure if the Uniform is able to be calibrated, but if not and you've maxed the setting, then it points that your grinder is not up to going fine enough. You're correct - if you're fouling your showerscreen, then you've max'd your dose potential.

I've started writing the shot routines down and what baffles me is dose and grind-size don't correlate well to shot time or flow, which is not how it should be (right?). What's left is either I'm making some monumental error in prep, or the machine has a ridicolous pressure setting from the factory.

Great! When it's not correlating, I'd suggest that something is not consistent with your puck prep. Are you weighing pre or post grinding?

On the pressure note, the 15bar factory is a bit high. Definitely grab the mod to step it down. That will help shot times slow a little, but not hugely. If you are bottomed out and flowing 17-50g 17 seconds, then even with a step down in pressure there's little scope for you to adjust from coffee to coffee.

As @aguirre.torrini mentioned and I would tend to agree, if your grinder can choke a machine, then that's the kind of grinder suitable for espresso to give scope for adjustment.

 

@jackspro, thank you for the reply I do measure pre and post grind as the Wilfa has some retention. After my last batch or results I knew I had to rule out (or in) the grinder. Therefore I went to the Tim Wendelboe cafe and explained my problem to a barista, after some back and forth said she believed my problem is due to either dosing too low or grinder not grinding fine enough (as has been pointed out). She gave me some of their specialty coffee which she ground right there (for free!), now she set their Malhkoenig grinder at 0.3 on the grinder scale, thats about as low as the machine would go.

This is where it gets interesting, because this surely should be the benchmark grind and here are the results:

REF: VST Basket (no coffee): 51gr of water in 8 seconds
16gr of coffee (VST) 48gr out in 9 seconds, notes: acidic and harsh (empty?)
17gr of coffee (VST) 51gr out in 12 seconds, notes: quiet, acidic, harsh
17gr of coffee (Stock) 51gr out in 12 seconds, notes: more acidic (yay VST?)
19gr of coffee (VST) 57gr out in 13 seconds, notes: harsh, acidic
20gr of coffee (VST) 60gr out in 13 seconds, notes: harsh, acidic

I suspect anything above 17gr makes contact with the shower and therefore suffers channeling badly, but that's just speculation. Anyway, the problem persists and at this point I don't know where to go.

 

Therefore I went to the Tim Wendelboe cafe and explained my problem to a barista, after some back and forth said she believed my problem is due to either dosing too low or grinder not grinding fine enough (as has been pointed out). She gave me some of their specialty coffee which she ground right there (for free!), now she set their Malhkoenig grinder at 0.3 on the grinder scale, thats about as low as the machine would go.

This is where it gets interesting, because this surely should be the benchmark grind and here are the results:

REF: VST Basket (no coffee): 51gr of water in 8 seconds
16gr of coffee (VST) 48gr out in 9 seconds, notes: acidic and harsh (empty?)
17gr of coffee (VST) 51gr out in 12 seconds, notes: quiet, acidic, harsh
17gr of coffee (Stock) 51gr out in 12 seconds, notes: more acidic (yay VST?)
19gr of coffee (VST) 57gr out in 13 seconds, notes: harsh, acidic
20gr of coffee (VST) 60gr out in 13 seconds, notes: harsh, acidic

That is really awesome of them to do that for you, and probably is the ideal route to take to eliminate. However, I suspect they ground it on an EK43 and it can do espresso, but you really need to bottom it out and have it calibrated to do so. I calibrate it to burrs just touching on finest, and there isn't a whole bunch of scope before it's too coarse. If they didn't have their EK calibrated as fine as it would go, then it probably won't do espresso. A better test would be to have some ground from their espresso grinder they use on bar.

I would say that it will be your grinder. Do you have any pals you can beg, steal or barrow off? Or, would you consider spending a little to upgrade?

 

Actually if you google it you’ll find that your grinder is not ideal for espresso.

 

Thank you. Yes, I've realized the Wilfa probably isn't ideal, but at this point its more about the fact that no grind is fine enough. Not the Wilfa, not a Stockfleths espresso grind and not even a Tim Wendelboe ground coffee seems to have much impact on the flow rate.

 

I know it's frustrating, but hang in there! All will come good and you'll be drinking awesome espresso ☕

 

Thanks, I'm not about to give up but I feel like sinomethg must be wrong here or the difficulty seems absurd 😅. I can find a Mazzer Super Jolly used but serviced for about 550$, there's also a Eureka Mignon Zero 55 for 690$. In addition, I see some rancilio rocky grinders between 250$ - 400$ depending on doser and new/used (but serviced). Not sure which to pick. I am serious about this so I dont mind investing in a good grinder.

Edit: there's also a baratza sette 270 for 580$

 

Out of all the grinders listed I would go for the Eureka Mignon. You can’t go wrong with it or with Niche Zero if you can find one

 

Small update, I went back to Tim Wendelboe this morning and got another free sample dose (these people are amazing) but this time from espresso grinders and not the EK43. And luckily the rule holds! 17gr in and 42gr out in 28 seconds!

I am therefore a proud new owner of a varia VS3 with an upgraded burr set. I looked at the Eureka but I don't like the adjustment button, and I've read about some issues with noise and aligment(?). Either way the Varia seems like a very good fit.

 

Small update, I went back to Tim Wendelboe this morning and got another free sample dose (these people are amazing) but this time from espresso grinders and not the EK43. And luckily the rule holds! 17gr in and 42gr out in 28 seconds!

Great stuff, and nice one on the persistence.

Enjoy! ☕

 

Did your Varia arrive? If so, how are you getting on?

 

Yeah, I actually picked it up same day from a local roaster, which also got me a good deal on some fresh coffee. The 9 bar spring mod arrived yesterday and getting a consistent shot has gotten much easier. Really loving it so far!

 

I wanted to thank you, @FancyLadSnacks for posting this. I have a Wilfa Uniform, which for months made great aeropress coffee for me, and good french press. I was a happy bunny, but then took it into my head to go for an espresso machine. The sage Bambino Plus was in my price range at the time, and I bought one second hand. It only came with a dual wall basket so I bought a precision ground single wall basket, set the Wilfa to 2 (because it chirps at 1) and found that I got 18g in, 46g out in just 18 seconds - horrid sour taste. Investigated online, and I'm well aware that my uniform isn't set up to be great for espresso, but that it could do it (even James Hoffman has shown that) so I asked Wilfa.

They said there must be a fault with the grinder after I'd sent them images of the grind, shown them the chirp on video, and explained the espresso issue. The Sage is 9 bar, consistent if unalterable 93 degrees - basically ought to be alright, 54mm admittedly but ...

Tamping pressure and puck prep (declumping and tamping level) seem OK. I guess I'll go for a Niche Zero when I can afford one.

It seems to me that your post, and others like it, imply that the Wilfa Uniform quite often cannot grind espresso fine, and even if it does has steps that are not helpful. You'd have to fiddle around with dose to fix that issue. But if quite regularly the Wilfa Uniform cannot get espresso fine, it does imply that perhaps it only works with pressurised (double walled) baskets out of the factory in a significant number of their machines.

I may never make espresso I truly think I've nailed. Sad. I'll give it a go though

 

Awesome, good to hear! ☕