liquidmetal wrote:Lucca m58 popping in. yes pls

Bill33525 wrote:My Quick Mill Evo 2 would like this upgrade.

baratzaboi wrote:My Mara 1st Line special (PL62S-T) is coming in tomorrow! So yes, consider me signed up for any early testing/prototyping. I'm new to the espresso game, but my background is in bicycle building so tinkering is definitely in my nature.

stevier wrote:I'd be interested as well. Alex Izzo Duetto v1, here.

Thanks for the posts! Good to know of your interest.

Another Quickmill E 61 user interested -- mine is a "Carola". (I would hope all the QM E61's are the same.)

You can get an aftermarket pressure gauge sitting on the grouphead.

Can we get something for the mushroom?
I'm actually wondering if the mushroom is dosed with threadlocker, else i think it should come loose sooner or later.

The PID looks pretty close to moisture from the steam wand.

For "hands-on" types and also theorists looking on, this sounds like a lot of fun!
As you know, I've already posted the "water debit" flow rates for the Bianca, on HB. There if needed. As a retired engineer I'm in the place where I can spend some time on Bianca performance measurement, so if you need some data to support your effort, I'll be happy to help , assuming your plan is non commercial.
One point that has started to become clear during my first couple of months with the Bianca, is that the paddle allows enough low pressure control to bloom or saturate the puck, before flow, whereas the pump on/off prefusion setup in the LCC has a different effect on the puck. Talking to my roaster about this, he has some theories and doubtless other users and HB testers will also. E61 groups pre-infuse in a very similar way to the LCC of course, but that preinfusion is not adjustable.
So it might be good to look for the adjustable valve to work at the preinfusion end of the scale, rather than rely on pump control.

Thanks Graham and welcome over here. Are you familiar with the boiler pressure preinfusion available with any non-plumbed E61 if your pump switch is adjusted where you can turn the lever just past the midpoint and the brew valve will open but the pump does not run? This results in a preinfusion with very low flow and pressure (under 1 bar). THis sounds like what you are talking about and allows any E61 to Bloom away! THe intended built-in E61 preinfusion is pump driven and usually on the order of 3.5 to 4 bars which can only allow the low flow saturation/preinfusion by bumping the pump, which is another option anyone has. Change how long and how often you bump the pump and it gives a lot of flexibility with preinfusion. One thing I really like about this approach is it is mostly manual and mechanical which I trust much more than electronic controls for longer life and more flexibility. That could change but it hasn't yet.

Also Graham, I tried to take a look at your plot in Jake's S20 project thread, and on the Bianca User Experience thread, but it cuts off the entire set of abscissa labels, which makes it unusable, at least for me.

jgood wrote:Another Quickmill E 61 user interested -- mine is a "Carola". (I would hope all the QM E61's are the same.)

Keep them coming. My sketches are almost ready to head to the valve maker.

Tonefish wrote:I think a lot would depend upon the thread pitch, and I wasn't necessarily set on a half turn since I may prefer better pressure adjust-ability rather than big changes in small angles.

One thing I've been thinking about is that it might be better to use maybe 2 turns of the valve to go from full flow to near shutoff just to give better resolution in adjustments. I've read that some of these half turn paddle valves (especially the GS3/MPs) have too big a change in too small an angle which can make them harder to control. I realize that is part of the design of that particular valve but it still seems to make sense to have a little more control. Thoughts?

I would say keep it just within one turn. It might get confusing having two full turns and hard to know exactly where you are within that range ( unless there is a pressure gauge/manometer that could be use to correlate to the paddle position within that two full turn range).
I would say a range from about 11 to 1 if looking at a clock face.

As far as pre-infusion, etc., on my machine I can do line-level pre-infusion and control the pressure with an in-line regulator. The pump doesn't come on and currently have the pre-infusion level set to 2 bar. Doing line level you don't have to mess with boiler pressure and the effect it would have on the brew temp.

AS far as this mod is concerned I am more interested in being able to regulate the flow towards the end of a shot than in controlling the pre-infusion rate since I can already do this now.

speedplay wrote:I would say keep it just within one turn. It might get confusing having two full turns and hard to know exactly where you are within that range ( unless there is a pressure gauge/manometer that could be use to correlate to the paddle position within that two full turn range).
I would say a range from about 11 to 1 if looking at a clock face.

I agree. Additionally, while a knob offers a wide range of adjustment, the tactile feedback of a paddle like that on Bianca has some distinct advantages. The paddle provides a better interface for muscle memory (hard to use a knob in the dark) and also makes smaller adjustments easier by virtue of increased arc length for a given angular adjustment. This is geek speak for saying it's easier to nudge a 2" long paddle a quarter inch to the left than it is to accurately twist a knob 1.75 degrees clockwise.

As far as pre-infusion, etc., on my machine I can do line-level pre-infusion and control the pressure with an in-line regulator. The pump doesn't come on and currently have the pre-infusion level set to 2 bar. Doing line level you don't have to mess with boiler pressure and the effect it would have on the brew temp.

AS far as this mod is concerned I am more interested in being able to regulate the flow towards the end of a shot than in controlling the pre-infusion rate since I can already do this now.

I'll defer to active Bianca users here, but not before I give my soapbox speech on why I think folks are willing to drop 8 grand on a Slayer...

•Line pressure limits maximum pressure but does not control flow.
•Gear pumps control flow but do not control pressure.
•A needle valve does not control pressure or flow rate directly. What it does do is something even better...

A needle valve controls the relationship between pressure and flow. The only way we have to quantify a given needle valve position is by measuring the water debit, which Graham has been kind enough to share with us. What controlling water debit does for us is control how quickly the brew pressure reaches the available pump pressure, or the maximum pressure the puck can generate; whichever is lower. Lower water debit will have a longer ramp, and will eventually reach a point where a given puck won't generate the full back pressure of the pump. Valve openings above this point will hit full pump pressure, and going lower will generate less and less pressure and softer and softer pressure ramps.

So, you can preinfuse all day long at 2 bar, but this is not even close to what Bianca allows you to do with the needle valve. As long as you get the grind right, you can have a steady and progressive preinfusion with a needle valve that allows and in some cases requires a grind that is obsurdly fine and brings out flavors that line pressure alone cannot match. No doubt that this approach may not be best for all roasts (some darker roasts just don't taste good like this), but I assure you that this is very different from your grandma's line pressure preinfusion. Using a needle valve allows pre-brew, which is unique in that it ends by itself, when the puck is sufficiently saturated to generate the full available back pressure that the pump provides (assuming the grind is fine enough to get you there). The puck (in concert with the needle valve, of course) defines this process and as such you are able to gently bring the puck up to brew pressure without manipulating the needle valve at all, if you so desire. Just set a pre brew flow rate and let the puck do the rest.

I think that is why folks buy Slayers. There's a genuine "magic" to what they can do, but Bianca offers even more, at the expense of losing the saturated brew group.

The "even more" is what some of this conversation is referring to in terms of profiling the pressure at the tail end and also the blooming technique that's been mentioned. You can take the pressure as high as you like during preinfusion (Jim S. and Ken F. Found that it takes around 3 bar to fully permeate a tamped puck...) and then cut the pressure (pretty easy) to bloom or hold it at any pressure you like (a little tougher, but plenty doable) to achieve a myriad or differing flavor profiles.

I bring all this up to make sure folks know that this needle valve idea is rock solid in terms of what you can do. Please don't overlook how powerful this tool can be on the front end of the shot when coupled with a brew gauge reading puck pressure. For folks with HX machines, I would suggest getting a tee fitting that you can insert Eric's group thermometer straight through into the group with a side port for a pressure gauge so you can watch the temp gauge for your flush and the pressure gauge for your preinfusion. No doubt you can monitor the flow to control things on the tail end and let the pressure fall where it may to give you what your after, but that pressure gauge in the group is key to really unlock the potential of the needle valve...

Super stoked to you taking this on, Jim!

- Jake

Tonefish wrote:That would be great. Any links?

You can google for
Isomac e61 pump manometer gauge 5530011 DN40

It's available from the following link
https://www.ferrari-espresso.com/produc ... 0011-dn40/

You need to use a sealant with it. My Loxeal sealant doesn't have the holding power and it comes off easily.
I'm not sure if it's really a good idea and the gauge will last with coffee getting in it.

Best price at this store: https://www.lamacchinadelcaffe.com/manometri-lelit.html
Wonder about shipping to US?