Handmade coffeemachine

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
Zadrot

#1: Post by Zadrot »

I think it will be interesting for you. After making first 2-boilers coffeemachine (it was simple, the video, that I made for Mark from WholeLateLove channel below, that time it was not completed yet, but already was able to make espresso and prepare milk)

I decided that making coffeemachine is very easy and I need to make something new to impress home baristas and (maybe) deal with factories which produce coffee machines.
Everyone told me that they want to have small coffeemachine with huge sensor screen, E61 headgroup and able to change pressure.
So, I started to make coffeemachine with E61, small brewing boiler (dimensions about 200x200x50 mm) and PID. I have bought big (7 inch) sensor screen



I made boiler of stainless steel and attached 1 KW heater like this.



I also have made steam boiler,



unfortunately I am not able to make small coffeemachine with big (2 l capacity) steam boiler. Thinking of using thermoblock.

To control temperature, I installed stainless steel thyristor inside the short tube that goes from boiter to the headgroup



So, the headgroup now looking like this



And have connected presure sensor with headgroup to control presure. Both: temperature (+ heater) and presure (+pump) are controlled with microcontroller. It was the start of my prototype. The frame is wooden, bad-looking and dangerous to touch.



Water heats quickly because of small boiler. It starts to heat the headgroup quickly because the tubes are short. After about 7 minuites able to make first shot. I think 7 minuites is a great result.
When controlling presure manually, you can do something like lever coffeemachine does: start with low presure (pre-infusion) increase (ramp-up) until 9 bars and ramp down. But it is boring to move your finger during process, because when you have customizable profile it is more interesting.
I have made 4 profile settings: pre-infusion, ramp-up, peak and ramp-down. You can set preasure and time for each, but you have to understand that presure increasing and decreasing is not imediatelly. It takes few moments and when you change settings the diagram below shows you possible presure during brewing:


Zadrot (original poster)

#2: Post by Zadrot (original poster) »

Now it works. Test:
The test is here. First you see the user-defined presure profile and at last you can see real presure profile.
What's next? I want to install scales to control weight during coffee extraction and make frame and do something with steam. I think, thermoblock will be enought for this project.

Zadrot (original poster)

#3: Post by Zadrot (original poster) »

Extraction with single portafilter basket

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yakster
Supporter ♡

#4: Post by yakster »

Nice looking machine.
-Chris

LMWDP # 272

BeesKnees

#5: Post by BeesKnees »

Great work! "the last mile is the hardest" as they say. Good luck with the rest of the project!

I don't have sound on this machine. What type of pump are you using?

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BaristaBoy E61

#6: Post by BaristaBoy E61 »

Welcome to HB!

Congratulations on your achievement! I will continue to follow your progress with great interest.

Best wishes for your endeavours!
"You didn't buy an Espresso Machine - You bought a Chemistry Set!"

vas

#7: Post by vas »

I don't have sound on this machine. What type of pump are you using?
It looks like it's a sound of a regular vibe pump with pulse-skipping modulation.

SandraF

#8: Post by SandraF »

Great job! How does the coffee taste?

Zadrot (original poster)

#9: Post by Zadrot (original poster) »

BeesKnees wrote:Great work! "the last mile is the hardest" as they say. Good luck with the rest of the project!

I don't have sound on this machine. What type of pump are you using?
Which one? The first (Xenia) has rotation pump, the second one uses ulka ex-5 which skips steps if the presure is higher that you need.

Zadrot (original poster)

#10: Post by Zadrot (original poster) »

vas wrote:It looks like it's a sound of a regular vibe pump with pulse-skipping modulation.
Right!
SandraF wrote:Great job! How does the coffee taste?
I do not drink espresso, so I cannot tell you the truth. But capuchino is nice.