Graham J wrote: I've followed this "long and rambling" thread with interest and learnt lots by reading through over a few weeks. It definitely influenced my decision to buy a Lelit Bianca, which I've had for a few weeks now. So, firstly thanks to Jake G, Assaf and others, for all the hard won knowledge and information.
I was fairly hesitant to post anything I've learnt from working with the Bianca, because of the above quote, but the intention is to be helpful and not annoying ....

It seemed to me that the flow rate data for the needle valve assembly might be interesting/useful, so here it is:

paddle position water in grms time (secs)
hard left 18 30
parallel left 42.7 30
45 left 70.3 30
90 degree 108.6 30
45 right 141.2 30
parallel right 180 30
hard right 191 30

I have graphed this but don't know how to upload graphs to the site. The graph is basically a straight-line increment w.r.t. flow, outside of the extremes. of paddle hard left (low flow) and paddle hard right(high flow).
Measurements were taken onto calibrated scales direct from the open group head outlet, with no basket. Group head temp 96C, water boiler temp 106C. 30 seconds flow was used in all cases, to relate to "water debit" calculations. (1 gramme = 1 cc. as you are doubtless aware)
To avoid irregular flow start, due to drainback or back flow, the lever was opened right before each measurement for 3 seconds, then closed. My checks show an even flow start within 1 second, provided this is done within a few minutes of a lever operation cycle.

Hopefully this information hasn't damaged your flow (sorry) and you may be able to relate this to your development of your own variable flow valve system.

Thanks Graham!

This info hasn't damaged my flow at all. I am super excited to see what Bianca has to offer for folks. That flow rate data suggests they are using a valve very similar to what I have picked out.

Adding graphs is best accomplished by saving a screen shot of the graph and uploading the image. I do 98% of my HB posts on my phone, which makes swiping the screen for snapping screenshots and cropping them a piece of cake. For those of you who have tried other fora on mobile devices and shied away from it (because most sites are terrible in mobile...) give HB mobile a chance. It's remarkably good. (Thanks Dan!)

The bigger question, of course is how are you liking Bianca? I'm very curious what your initial impressions are in terms of ease of use (controlling pressure, doing things you intend to do...) and what you're noticing in the cup. Please share if you have time.

Cheers!

- Jake

Thanks Graham!

This info hasn't damaged my flow at all. I am super excited to see what Bianca has to offer for folks. That flow rate data suggests they are using a valve very similar to what I have picked out.

Adding graphs is best accomplished by saving a screen shot of the graph and uploading the image. I do 98% of my HB posts on my phone, which makes swiping the screen for snapping screenshots and cropping them a piece of cake. For those of you who have tried other fora on mobile devices and shied away from it (because most sites are terrible in mobile...) give HB mobile a chance. It's remarkably good. (Thanks Dan!)

The bigger question, of course is how are you liking Bianca? I'm very curious what your initial impressions are in terms of ease of use (controlling pressure, doing things you intend to do...) and what you're noticing in the cup. Please share if you have time.

Cheers!

- Jake

Hi Jake and thanks for the information on H-B posting.

Here's the graph of Bianca flow rate, previously mentioned:


I'm liking the Bianca a lot and it has proved reliable, repeatable and well constructed, thus far! Still pretty early in our house sharing though!

It's an easy machine to set up and use initially, as one can just replicate an existing workflow onto it and get the grinder and basic brew dialled in, while leaving the paddle alone. Next step then is just adding some preinfusion via the LCC (Lelit control Centre) which is a simple and neat interface. Its equally possible to use the paddle to control preinfusion flow, pressure and time, but the LCC is useful to lock a p.i. setting down, or when the erstwhile barista is bleary-eyed or distracted!
Once some pleasing espressos and other beverages are in place, then it is time to bring the paddle into play and add some slow ramp-ups and/or early pressure reduction, varying taste by changing extraction and extraction rate. This latter process has taught me more about the differences between sour and bitter and fast or slow extracting flavours, than I previously understood. Reading the erudite posts and reviews by DK, another-Jim et al, becomes a lot more meaningful when a home barista can conduct some taste-trials and experiments of their own!

The UK Lelit distributor, Bella Barista, retained DaveC (Dave Corby, who did some test work for Lelit on the prototype machines) to write a very useful 26 page Userguide, which sits alongside Lelits own handbook and adds more detail, including eight useful shot profiles in detail. These have supporting videos of the profiles in use. Using these, alongside Lelits own Bianca shot profile videos, are enough to get a new user familiar with how to profile and the anticipated outcomes.
Regarding taste experiences, I'm reluctant to launch into the pseudo-poetic descriptions we all no doubt read, but I will say that using the pre-infusion and shot profiling options, I can more closely match the tasting notes of the two Roasters I use, than ever before. They both make their tasting notes using La Marzocco saturated-group machines, which are too large and too costly for me. To replicate their tasting notes, I use their basic preinfusion and brew settings, but ignore the temperature - I find so far that the Bianca needs maybe 2-4 degrees C higher than the LM reference.
The same LM machine type, LM Strada with grouphead gauges, was used by Bella Barista to supply tasting references when I was making a purchase choice between Bianca and other E61 DB machines. It was pretty clear that the Bianca could arrive closer to the intensity and clarity of the LM shots than comparable machines, which mostly have limited or no profiling. I was not that interested in a number of well-finished machines from various quality manufacturers that are all very similar in components and design and function. The ability to easily change and adjust profiles and various other parameters makes this machine quite different and a lot of fun, for me.

The LCC has some other useful functions, such as programmable standby and separate adjustment of steam and brew boiler temperature. A deeper dive allows heating (PID) and pump parameters to be edited, with an easy reset to original profiles, if you screw up! There is another DaveC video on this and its unlikely to be something owners often need. Pump pressure adjustment is set up for easy access under the machine and all the gauges track quickly, zero out any residual and hold levels without flicker. The detail and thoroughness around the moveable water tank, tracking of the filter life and some other details, shows that some conscientious development has been allowed to take place.
I hope you find some of this useful/interesting.I'll post any other useful stuff on the Bianca main thread in due course.

Look forward to reading the next part of the "long and rambling path" and seeing the machining and build of your very own specialist design!

Graham J wrote:Hi Jake and thanks for the information on H-B posting.

Here's the graph of Bianca flow rate, previously mentioned:
<image>

I'm liking the Bianca a lot and it has proved reliable, repeatable and well constructed, thus far! Still pretty early in our house sharing though!

It's an easy machine to set up and use initially, as one can just replicate an existing workflow onto it and get the grinder and basic brew dialled in, while leaving the paddle alone. Next step then is just adding some preinfusion via the LCC (Lelit control Centre) which is a simple and neat interface. Its equally possible to use the paddle to control preinfusion flow, pressure and time, but the LCC is useful to lock a p.i. setting down, or when the erstwhile barista is bleary-eyed or distracted!
Once some pleasing espressos and other beverages are in place, then it is time to bring the paddle into play and add some slow ramp-ups and/or early pressure reduction, varying taste by changing extraction and extraction rate. This latter process has taught me more about the differences between sour and bitter and fast or slow extracting flavours, than I previously understood. Reading the erudite posts and reviews by DK, another-Jim et al, becomes a lot more meaningful when a home barista can conduct some taste-trials and experiments of their own!

The UK Lelit distributor, Bella Barista, retained DaveC (Dave Corby, who did some test work for Lelit on the prototype machines) to write a very useful 26 page Userguide, which sits alongside Lelits own handbook and adds more detail, including eight useful shot profiles in detail. These have supporting videos of the profiles in use. Using these, alongside Lelits own Bianca shot profile videos, are enough to get a new user familiar with how to profile and the anticipated outcomes.
Regarding taste experiences, I'm reluctant to launch into the pseudo-poetic descriptions we all no doubt read, but I will say that using the pre-infusion and shot profiling options, I can more closely match the tasting notes of the two Roasters I use, than ever before. They both make their tasting notes using La Marzocco saturated-group machines, which are too large and too costly for me. To replicate their tasting notes, I use their basic preinfusion and brew settings, but ignore the temperature - I find so far that the Bianca needs maybe 2-4 degrees C higher than the LM reference.
The same LM machine type, LM Strada with grouphead gauges, was used by Bella Barista to supply tasting references when I was making a purchase choice between Bianca and other E61 DB machines. It was pretty clear that the Bianca could arrive closer to the intensity and clarity of the LM shots than comparable machines, which mostly have limited or no profiling. I was not that interested in a number of well-finished machines from various quality manufacturers that are all very similar in components and design and function. The ability to easily change and adjust profiles and various other parameters makes this machine quite different and a lot of fun, for me.

The LCC has some other useful functions, such as programmable standby and separate adjustment of steam and brew boiler temperature. A deeper dive allows heating (PID) and pump parameters to be edited, with an easy reset to original profiles, if you screw up! There is another DaveC video on this and its unlikely to be something owners often need. Pump pressure adjustment is set up for easy access under the machine and all the gauges track quickly, zero out any residual and hold levels without flicker. The detail and thoroughness around the moveable water tank, tracking of the filter life and some other details, shows that some conscientious development has been allowed to take place.
I hope you find some of this useful/interesting.I'll post any other useful stuff on the Bianca main thread in due course.

Look forward to reading the next part of the "long and rambling path" and seeing the machining and build of your very own specialist design!

This post would make a great start of a Bianca thread! Welcome to the world of profiling. Thanks for sharing ... and the likely motivation for Jake to get his project done. Cheers!

Thanks for that! I'll take your idea onboard. There are a few experiences regarding the Bianca that didn't seem relevant here, so I'll add those and look to start a Lelit Bianca experiences thread.

Tonefish wrote:This post would make a great start of a Bianca thread! Welcome to the world of profiling. Thanks for sharing ... and the likely motivation for Jake to get his project done. Cheers!

Yes. Motivation. That's what I need

It's been a busy few months. Having finalized the conceptual design, what's been left is to physically verify all the group and cap dimensions before manufacturing the sealing gland and then boring the group cap. Both of these tasks have meant having a back up machine available so I don't have to go without espresso should complications arise once I pull the group and make a few chips. That's where Baby Gaggia comes in. Thanks to Lady Luck, she came with a NEW Rocky still in its box. I feel about the same as all y'all with respect to Signor Rocky; he's a great starting grinder and pairs well with a stock Silvia or Gaggia, but not something I feel any need to remove from the box. If anyone needs a 17lb travel grinder, let me know...

So, now that I have the ability to pull a few shots with the Gaggia, I have officially run out of excuses (except that I broke my group thermometer, and that sucks. I have to use the natural logarithm of the expected resistances at various temperatures in order to figure out the Beta value of the broken thermistor, which is just annoying in itself, but then every single brand of thermistor calculates their Beta at different temperatures, so when I think I've found the right one, it turns out I have to test the thermometer at those temps and then find that once again I'm close, but no cigar. Ugh...), so it's really time to make some movement on this.

One of the reasons I decided to go with 4mm quick connect fittings is so I can just pop some 4mm plugs in them and swap my pressure gauge and thermometer around until I figure a clean mounting solution. It also affords me an easy approach to throw in a thermocouple for datalogging or even a pressure sensor, but I'm getting way ahead of myself. First thing first is to get the valve in the group and have myself a commercial HX clone of Bianca. I should be pretty happy with that right up until I'm not.

Graham,

I really appreciate you chiming in and posting your water debit data. Have you considered following DaveC's advice and calibrating to the paddle so you can stop the flow at the full left position and gain better control at the beginning of a shot. This also gives you the option of a soak phase independent of the LCC programmed preinfusion/soak intervals, which could be rather fun to experiment with.

Alright, hopefully I can find some time in the coming weeks to get a functioning workflow with the Baby and take the S20 offline for a few days to get things moving along.

Cheers!

- Jake

Jake - I have a rule: every day starts with an espresso and ends with an espresso from the GS3 and the Versalab. When doing large conversions it helps keep boundaries on my childish inner self. The repercussion is "no espresso for you".

If push comes to shove there is always rescue tape (yes - my name is assaf and I admit to being a rescue-tape-a-holic;).

BTW my first ever "real" espresso machine (1992 or so) was a Gaggia Caffe Classic (a baby is metal clothing). How I loved that machine! The best espresso was the 2nd of the day after (if my
Memory doesn't fail me) a 15-17 minutes warm up. I remember doing a "pretend" first pull which I later learned was called a "flush".

I would have loved to have make a coffee with it today.

That's a rule worth living by!

I'm not sure how I could bring my machine back into service with rescue tape after drilling a sizable hole into the jet cap, but I suppose that means I haven't push the limits yet, doesn't it?

This morning I pulled the cap and got my detailed measurements. The good news is that I was very close in my rough guesses! Below is how things shaped up with final dimensions in place:

I didn't have enough room to offset the sealing O-rings, and I made the decision to use a second O-ring as a backing ring to position the sealing O-ring on the machined surface of the needle valve barrel. I thought about using something more rigid, but the O-ring should do the job nicely and allows for a smooth bore inside the gland, rather than a captured O-ring groove. The gland is only 0.200" in length!

After a quick trip to the 3D printer, I have the prototype in hand:

Now to see if we can replicate this in brass...

The bore of the cap came right in at 14mm when I measured it this morning, so I will be able to clean that up to 9/16" in the lathe and get a nice crush on the outer O-ring and an excellent seal to go with it. The interference between the gland and O-rings on the barrel of the needle valve is exactly as I hoped. This should work!

Cheers!

-Jake

I really appreciate you chiming in and posting your water debit data. Have you considered following DaveC's advice and calibrating to the paddle so you can stop the flow at the full left position and gain better control at the beginning of a shot. This also gives you the option of a soak phase independent of the LCC programmed preinfusion/soak intervals, which could be rather fun to experiment with.

Yes, the paddle is easy to reposition on its spline and I've used that a couple of times. The 200 degrees or so of possible paddle movement complete the valves more linear flow range anyway.

Generally, early intervention (inside 3 seconds from pump on) with the paddle can make a big difference in time to first drip and flavour profile on light/medium roasts. Less so on darker roasts. These then become longer timing shots with 10-15+seconds pre-infusions and a ramp up as drip turns to stream and the E61 pressure gauge starts to rise above 2 bar.

If a shot tastes sour/sharp, reducing the grind weight to get more extraction would be one way to go. But keeping some positive pressure on the puck with the paddle and slowing down p.i. by early intervention actually works very well. Possibly, bringing up those slower extracting flavours or extracting the lower layers of the puck more.This can be a better outcome than switching pressure on/off using the LCC.

It is useful to record the paddle position and the E61 gauge against the shot timer, so that everything doesn't become too subjective. I'm drinking a lot of espresso sitting in front of my Grinder and Brew Settings spreadsheet, but there are worse challenges to have!

Graham J wrote:The UK Lelit distributor, Bella Barista, retained DaveC (Dave Corby, who did some test work for Lelit on the prototype machines) to write a very useful 26 page Userguide, which sits alongside Lelits own handbook and adds more detail, including eight useful shot profiles in detail. These have supporting videos of the profiles in use. Using these, alongside Lelits own Bianca shot profile videos, are enough to get a new user familiar with how to profile and the anticipated outcomes.

Hi is it possible to read this 26 pages guide ? any info on pressure profile sound good to me

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