Breville Dual Boiler "Slayer shots"? - Page 78

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

#771: Post by bcarlson65 »

Great creative ideas in the forum folks, much appreciated.

For conversation only - I'm wondering if anyone has thought of using a gear reducing method to turn the small rotation of that "slayer converted water knob" into a much larger one (think of 1st gear on your bike). That might make for a much easier mod using stock parts using that small range. Just thought I'd throw it out there.

Basic idea in my current form is to attach a larger gear on the knob shaft and then getting a small one to turn it. The gear ratio could be picked to best fit the profiling range needed. (would think 4 or 8-1 would be a good start) .

Have not done the slayer yet but should be happening in the next week as I get the scale incorp in the drip tray.


#772: Post by MisterT »

Hi @bcarlson65

I've read all sorts of information and was surprised that only you asked the exact same question that's been on my mind. I personally don't want to lose the hot water functionality and I can't think of any reason why we can't add another needle valve. I was going to see if I can fit it through the tamper holder location and have a horizontal lever. I'll post again once I've started testing, but would be interested to know if anyone else has tried it.

Cheers, T


#773: Post by maximatica »

I had mentioned (perhaps this thread) that I planned to make a handle to increase the ratio for the needle valve.

I have been using it for about 6 weeks and have a few last fine-tuning (aethestic) mods to do.

I should either have them done by Mon/Tues or if not, I will post the file so others can fit it.

Increases the movement by a factor of probably about 4-6 which has to be finer than the increase of a different needle valve.

But the movement is actually only about 20-25 degrees so with the stock valve and the normal knob it would be a chore to keep it tuned during the shot.

It's a 30 second install, once you have the knob off the lever fits into the 3 armed recess and you are done.

Stay Safe!




#774: Post by luvmy40 replying to maximatica »

Nice! I'd love to buy or print one an try it out. Will you be selling them or releasing the .stl?


#775: Post by Jessipoo »

Hey all, it may be in one of the 78 pages of this thread but I can't easily find the information so here we go!

Drinking mostly medium to light roast, did the slayer mod. Struggle to get the 9 bar pressure at the high point and the shot comes out pretty quick too (does seem to taste pretty good though but I also do have some sugar and milk in there so it does help mask a lot)

If I grind too fine, the pressure doesn't go up.

I'm not sure what adjustments to do or if the slayer mod changes how to extract.


#776: Post by luvmy40 replying to Jessipoo »

What pressure do you see with the blind filter or cleaning disc and the water valve wide open?


#777: Post by Jessipoo replying to luvmy40 »

10 ish bar, so it definitely can get there, I just find when I grind finer, which is what you'd have to do with the slayer mod due to the extended low flow pre-infusion, that it gets stuck and then a good 30 seconds can pass until anything comes out at the 2-3 bar pressure pre infusion, perhaps I have to increase the flow a little more than I am doing now

Team HB

#778: Post by JRising »

Jessipoo wrote:and if it's not entirely sealed, then I'm losing some water flow?
No, but you'll have a leak that never stops.


#779: Post by Jessipoo replying to JRising »

ya the spigot is not perfectly sealed with the piece I put in there and there is a little high pressure water that spurts out of there once in a while, other than water going through there, and lowering some of the water flow from the group head, it hasn't been too much of an issue though I should get a tighter fit


#780: Post by Keegzy »

Did I miss the link for the file for 3-d printed arm? Looks good.