Breville Dual Boiler "Slayer shots"? - Page 72

Need help with equipment usage or want to share your latest discovery?

#711: Post by athoangphan »

I took a Clippard needle valve apart today and just wanted to share what the needle looks like.


#712: Post by doublebase »

I just read from the beginning to Page 40, may I ask is there a way to splice a switch to the pump without drilling a hole on the machine. And the benefit of this is to mimic the Scott Rao stop and bloom method? I just placed my BDB order and would like to do the Slayer Mod first. Being a complete newbie to espresso machine and this community, I will keep reading these Modding threads and see if there is any mods I could make to the machine.

By the way, some people mentioned Acacia mod, may I ask what is it?

Cerini Coffee & Gifts: official US importer for Olympia Express
Sponsored by Cerini Coffee & Gifts
pcrussell50 (original poster)

#713: Post by pcrussell50 (original poster) » replying to doublebase »

You can run a cord with a switch to operate the pump, out the back of the machine and around to the front where you don't have to cut anything. That's what I did before I converted to a rotary pump.

LMWDP #553


#714: Post by mrjag »

Another option is to repurpose the magnetic tamper storage slot. The magnet-strip at the top of the slot is held in place with some hot glue. Open up the top of the case, carefully pull the magnetic strip off, and now you have a decently sized hole to rig a new button/switch through. Bonus points if you can 3d-print something to mount it nice and flush with the rest of the case.

Need to reverse back to stock? Slap the magnetic strip back in place and secure with another dab of hot glue.


#715: Post by enshongmiranda »

I just registered to say thanks to all the great guys who made this possible. I finally did this mod yesterday. After wasting around 150g of beans and some water, I've finally worked things out. I didn't expect the espresso to have a very noticeable improvement from the "Slayer-like" shots I've been doing. It's amazing.

What I did with my knob is tie a zip tie around it and stuck a wood "stopper" on the side of the machine so the "head" of the zip tie stops at the point where I get 1.5g/s flow rate. This also prevents me from fully closing the needle valve while the pump is still running as I'm afraid that might cause too much stress on the pump and the needle valve. Perhaps that causes the needle valve not closing fully anymore in some users? My fully open flow rate is around 8-8.4g/s. For the coffee I use, start at 1.5g/s flow until I get around 3g of espresso in the cup which happens at around 25-30s (pressure rising to around 7-8bar) then fully open up the knob which brings it to 9bar ending the shot at 34-36g out at ~45s. I don't bother with a decline for now. I get really good consistency shot to shot that I've programmed the double shot button for volume while the single shot acts as purge after each shot. So my workflow is:

1. Knob at min flow (1.5g/s)
2. Press shot button to start
3. Turn the flow up to max when 3g espresso is in the cup
4. Press shot button to stop at 32-33g in the cup which coasts to 34-36g final out
5. Press single shot button for purge
6. Turn knob back to min flow ready for the next shot

I do use the Dual Boiler in a very low volume cafe. I hope Breville considers making a pro/commercial 2-group version of the Dual Boiler! Lance Hendrick said he's talking to Breville about it trying to convince them. I hope he succeeds! I'm just amazed at how good this machine is. I wish someone can make a custom replacement handles for the water and steam knobs though!

After the mod though, has anyone noticed the wand putting out a stronger steam? I've set mine to 140ºC before but it seems like the steam is now stronger after the mod. I like it but I'm kinda concerned if it might damage the steam boiler or the o-rings on the tubes.


#716: Post by cmin »

So I ended up randomly acquiring an 920XL that's had the valve etc mods done. Still getting used to it with settings and grind, I've used a Slayer which is just stupid easy of set it and forget it, set needle valve and pull glorious shots one after another. Just have to get used to how sensitive the knob is on this machine. Looking forward to playing with this machine more. And the warmup time is insanely fast, steam is excellent (owner actually drilled the holes slightly out think .40 for stronger steam). I was also all these years never really sure of the BDB looks, even though I've used them years ago, but actually having it in the kitchen, I actually really like how it looks.

I do notice profiling my pucks are sticking to screen every single time, but realize someone mentioned when you stop shot keep the knob at the min level and press manual again to purge the puck off.

User avatar

#717: Post by lancealot »


Can you post a picture of your knob / ziptie / wood dowel mod? Sounds cool but I am having a hard time visualizing it.

Urnex: 100% dedicated focus on coffee and tea cleaning
Sponsored by Urnex

#718: Post by benja »

Hello All,

Wow this is a monster thread, full of great info, just took a bit of reading to go through it all! Am soon to get myself either a BDB and try some mods, or was also toying with the idea of a Lelit Bianca.

But anyway, just quickly, I am just wondering has anyone tried putting a potentiometer (variable resistor VR) in line with the power line to the pump?
I was watching Lance Hedricks VDO on YT (starting at 8:47 about his Gaggia Classic pro mods and see he has a simple VR in series to the power line going to the pump, controlling the current to the pump thereby controlling the output of the pump and therefore controlling flow. Could a similar thing not be wired into the the BDB on the power or signal/control line going to the pump, so you'd press the desired button (single/double/manual) and then control flow with the variable resistor using the built in manometer for reference, and then all other pipe mods and electrics stay as factory and can keep the hotwater spigot in use as well?

Thoughts appreciated.


#719: Post by enshongmiranda »

lancealot wrote:enshongmiranda

Can you post a picture of your knob / ziptie / wood dowel mod? Sounds cool but I am having a hard time visualizing it.

Sorry if I'm a bit late. Here's what I did to my water knob.

User avatar

#720: Post by lancealot »

those are cool! 8)