CarefreeBuzzBuzz wrote:Peter what about the unaffordable Slayer Slayer valve?

I'm not sure what it offers that the Jake valve doesn't. But the guy who developed that valve is exactly the kind of bloke who is destined for not only expanding the capability of the BDB for the rest of the community, but pushing back on that old envelope for all of espresso.

-Peter

I went back to the drawing board. Prior to my Niche, I would always just tap on the side of the portafilter to settle the grounds and then tamp. For some reason when I got the Niche, this didn't work at all for my Silvia. So I started doing WDT. Well I went back to my old ways now with the BDB, and it pretty much solved my extraction issues. Weird. But whatever. I had a Guatemalan Gesha this morning that took about 25 seconds for 1st drops. 18g in 36g out in just about 90 seconds. It was fantastic. I plan to go a little coarser tomorrow morning. But either way, I'm getting the hang of these shots.

Hi there,

At first I would like to say thanks for everybody, especially Jake and Peter for thinking of such clever mod. It's a reason why I chose the BDB as my very first machine.

However, having tinkering with the hot water knob for a few months, I think what could I do to achieve a more precise way to adjust flow-like having a on-off switch of some sorts.

And I have finally done it today. See the diagram below.



- Basically, I added another water path between the brew boiler and the group head, which I put in a needle valve with higher precision. This is the "pre-brew" path which I adjusted the flow to 1.5ml/s.

- Then I added a kind-of on-off switch to the existing hot-water-knob-needle-valve path.

- Both paths' ends and opens are connected with two side of a T.

- So when I close the switch, water will flow through the *new* pre-brew path. When the switch is opened, water will flow through both paths. See the video for the mod in action:
This is how the tubings go in my machine, and a close-up photo of the switch. Red is the pre-brew path, yellow is the "old" needle valve for full flow.





In the next step, I'll find better tubings and connectors, then drill a hole on the machine cover to put the switch there for easier access.

Nicely done, Tung.

I like this. You get the repeatable "2-speed" approach of Slayer, AND the variable "anywhere I want to go" flexibility of Bianca.

Bravo!

-Jake

Brilliant, Tung.

Not so many years ago, 2017 time frame? I had my BDB and other than the "quiet mod" (brass necked pump with commercial brass OPV), I was soldiering on making excellent espresso just with the inherent temperature stability of the BDB and the factory pre infusion which is still better than most machines out there, which have none. At the same time, I was observing and occasionally conversing with two top-dog GS/3 modding mafiosos, Assaf and Dick Green. We came to refer to the GS/3 as "a platform for mods." And I was jealous because I wanted a platform for mods, too. That was then. And this is now. And right now, I feel like the sky's the limit in terms of the BDB as a modding platform. So happy. And I'm made even happier every time Tung or someone else (and there is a slowly growing number) comes along with yet another mod to make ever better espresso.

So far I see out there:

-In the low and slow pre infusion camp: , the on the fly pre infusion mimic of the Bianca, now Tung's two path solution (which is more is Slayer mimic).

-The hard, fast, high flow, high pressure pre infusion camp, mimicking commercial spring levers. I do this with my rotary pump and separate control of the solenoid. Others like Mitch have taken over separate control of their solenoid, but still using the stock vibe pump.

In both cases, we taper down the flow later in the shot, a technique that has become de rigeur for enhancing sweetness.

Plumbed, rotary, commercial solenoids, commercial OPVs, it's all been done, and the sky is the limit. Quite the "platform" at the end of the day.

-Peter

Thanks for the kind words, Peter and Jake

I have been running my BDB with this mod for a few weeks now. So far so good, I just love the consistency it brings to my routine. But I'm afraid the plastic parts might fall eventually so I'm ordering brass and stainless steel tees, ball valves and needle valves-these will come in a week or so.

However, I have an idea of replacing the ball valve in the "full flow" part with a solenoid valve, which will be connected to a 3-position toggle switch. The switch will override the manual button and work like the Slayer paddle:

Position 1: Everything off.
Position 2: Pre-brew state, pump on, "full flow" solenoid valve closed.
Position 3: Full flow state, pump on, "full flow" solenoid valve open.

But I have no idea how to tie the toggle switch to the manual button. Peter and Jake, can you give me some advice on how to get this done?

- Tung

So, not exactly a Slayer shot. Not even a shot at all, per se. This is using the needle valve to set a light drip, for well, a single serve drip coffee.

12.0 gram dose, drip ground, 190ml teacup: I used a paper disc in the bottom of the basket. Although it isn't necessary.

-Peter

Nice tinkering Tung!
Hopefully some of you guys might find my cartoon useful. I currently have these mods almost done as you can see . Its an update to my previous post by adding a metering valve bypass solenoid(2) and a cheap little 3D printer pulley to correct the valve sensitivity (3.2 turns to 0.53 turns for 1-6g/s while being nice and linear). I figured I may as well throw some more junk in there while I'm updating the old corroded shower head, OPV, and waiting on my Niche to show up.

Now I can have actual Slayer shots, active flow adjustments, or just use it with normal features.

Holy Franken-Breville, Batman!

pcrussell50 wrote:So, not exactly a Slayer shot. Not even a shot at all, per se. This is using the needle valve to set a light drip, for well, a single serve drip coffee.

Nice. I've been doing this as well regularly for quite some time now. I prefer different ratios and grind settings though. 14g coffee ground at a setting somewhere between espresso and drip to ~100ml yield.

Speaking of longer ratios: Has anyone tried to replicate the "Rao Allongé" on a modded BDB? From what I understand you want 18g, 90g yield brewed within 30s at a constant flow rate with a peak pressure at 9 bar.