pcrussell50 wrote:For the longest time, a lot of us just accepted that with light roasts, you were just bound to get kind of ugly pours, and that good "pron" was from a bygone era of darker roasts and blander flavors.

However... in my best estimation we are on the precipice of taking our Slayer mods and going next level. Some of you already know what I'm talking about. Mitch/cccpu does. And so does Rob/ImaWriter. And probably some of the other long term regulars who aren't as big mouthed as me. But it's a big step... Unless some hopeful research by Mitch pans out. It might not however. Vibe pumps may not be capable here. It would be nice if some more blokes could try what I talked Mitch into trying, so we could get at least a small base of users. Michael/CarefreeBuzzBuzz knows too. But he has an actual Slayer. Mike if you can take out your gicleur without feeling like you're performing brain surgery on your child, you might be able to do the "puck smasher" PI that I'm talking about. And don't be bashful just because this is supposed to be a BDB thread. Happy to talk about how we could do this with Slayer.

I can't participate because I'm too far over the top with my rig, though it's for sure a smash success with my capability. Rod Gonzales could do what I'm doing. But he might still be in the honeymoon phase of his plumbing guess and rotary conversion.

-Peter

Peter, your "big mouth" has helped too many of us to mention. A post or 3 back, you mentioned that longer PI have become perhaps a little less the thing. You also remarked...think it was you...so much depends...as always on the coffee being used. How freakin' TRUE that is. I am so pleased with the few mods I've done, though not every coffee...as we all know benefits from reduced flow-brew pressure at the last 3rd. Yes, that awesome spring lever emulation can add a bit of sweetness to many coffees, but darker roasts like Klatch Belle seem to be just fine with a medium pour rate, and shut down at 8.5-9 bar. Funny how this hobby works. BTW, I read all the posts regarding your Smash the puck exploits! I'd think those with a rotary pump and a bit of courage should give it a shot...pun intended. FWIW, I'm loving my BDB and treat it with proper water and proper care.

Roberto! You are much too kind and humble. I have always looked to you as more of an artist and taster than I am. I am more of a technician myself though I am always trying to develop my palate and learn. Thanks to you for reporting back on your experience here and sharing. People can learn a lot from your perspectives on beans roasting processing expected results from this profile or that, even experiments with different temperatures.

I just today picked up a bag of a Sumatra coffee. Only to find out from some knowledgeable baristas that Sumatra's are known to be hit or miss. I will start in on it tomorrow. But now I'm fully expecting challenges.

-Peter

Ceramic_Mug wrote:Thanks guys, here's a few more pics to accompany the underhood photo and inspire other modders.

- Parker NM series metering valve with 1/8 NPT ports

• Quite expensive...but not bad when you find one NIB online for 75 bucks

• The stock nylon fittings and silicone seals fit right on (no snip = reversible mod)

• The valve cap was drilled and tapped along with the stock valve's splined tip. A touch of red threadlocker and they're mated.

image
image

- Here's a pic of the stock needle adjustment range from 2-6g/s

image

- And the new flow curve. The curve has about half the sensitivity I was hoping for (using a Cv calculator and neglecting other system restrictions) but it's fairly linear and plenty good enough to smoothly taper off shots and dial in the rate to within 0.25g/s of the target.

image

Where can we get this valve online?

Hi! Just wondering - is there a page I can find all the available mods to do for a BDB? I have a BBE but am leaning towards a BDB to get slayer type like shots but I can't find the details of all the mods needed to be done to do that. Thanks!

Here you go:

Breville Dual Boiler Mods and Maintenance

Ahmad H. wrote:Where can we get this valve online?

I got it on ebay (70ish) but I'm sure you could order it directly from Parker or a lab supply place (maybe around 150?). This one is the straight brass NM but based on my finding I would get a brass 90 degree NL valve to make packaging and use easier.

I rarely make posts with little productive content in them. BUT you guys are heading down a path I've always hoped would happen with this platform... and I'm not talking about any specific mods here. What I have always hoped for was for competent and skilled modders to get hold of this BDB platform and start taking things next level. Just as you are doing it makes me happy and proud. Well done all.

My current status is MUCH simpler than where you are headed with the current discussion, even if it doesn't seem like it:

-plumbed
-external rotary pump (under the kitchen sink)
-needle valve flow control ("Slayer mod" more aptly Bianca)
-external solenoid on/off in left of machine
-external pump on/off on right of machine

These last two, allow me to bypass the 90s firmware limit. BUT more importantly, the ability to goose the pump on and off with a flick of the switch allows me to mimic the Londinium pre infusion method.

None of this is as technically next level as what you guys are doing. But I feel like it is the place I want to be if not in the technical space, but in the extraction space.

I created a BDB thread about "the Londinium mod" as an adjunct to the "Slayer shots" thread here. The two are not incompatible. Not an either/or situation where you have to choose one or the other. They are compatible with each other. So you can have both.

Anyway, well done everybody.

-Peter

Thank you for your works Peter and Jake. Been looking for my first espresso machine, I think I would give BDB a try and slayed it. But I am wondering if I slayed the machine, could I perform the backflush as the manual instructed? Just finished 1/3 of this thread and I will keep reading experiences from fellow members.

Yes you can do the factory back flush. Just make sure the needle valve is open and it will back flush exactly as normal.

-Peter

Here's a quick vid of my third round of mods nearly completed except for a pulley that's trapped in shipping limbo. Also, I'll reiterate what's been said many times, the brass OPV is outstanding. Rock solid pressure.
This little compartment behind the back panel is perfect for tucking wiring and components away from the splash zone.