DIY Bean Doser / Counter - Page 2

Grinders are one of the keys to exceptional espresso. Discuss them here.
Agajohn (original poster)

#11: Post by Agajohn (original poster) »

here are a few test runs. still needs some adjusting and tightening of the screws.

Agajohn (original poster)

#12: Post by Agajohn (original poster) »

here is a picture of all the failed attempts and a picture of the finished product.

cant decide which i like more, having finished the project or having a clean desk again. lol

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#13: Post by STG »

Dude. This is unbelievably cool. Nice work. I like the design a lot.

I know this would add an order of magnitude of complexity but it feels like a ramp up then a ramp down followed by extremely slow rotation for the last 2g or so would be what something like this needs.

Can you give me a high level overview of the electrical components you used including whatever you used to control it?

Also what CAD program is that? Really cool project. Cheers.


#14: Post by graphidz »

Hey man awesome project! Can't wait to see where this goes in the future.

How much is the width between the threads of the bean pusher thingy? Tighter threads with lower depth might make for a more accurate dosing. It'll be slower and limits the size of beans that fits though.

Also any opinions on using a higher vs lower dozer height to the catch cup? I'd assume a lower height would limit the impact of the on the scale as the beans fall down and can improve the accuracy of the programming.

Agajohn (original poster)

#15: Post by Agajohn (original poster) »

Thank you! Good idea with the adjustable speed.

The circuitry is as simple as it gets.

Its a nema 17 stepper motor
Driven by a A4988 driver
Arduino nano
Hc711 load cell ( for the scale)
A voltage regulator ( the 24v adapter feeds the motor, i use the regulator to take the voltage down to 5v to power up the logic side)
And an OLED display

Agajohn (original poster)

#16: Post by Agajohn (original poster) »

For CAD i use fusion 360

I used to use simpler CAD software like tinkercad but im starting to get more comfortable with fusion and its alot more powerful and professional

Agajohn (original poster)

#17: Post by Agajohn (original poster) »

I played around with different auger teeth sizes, i did start with bigger gaps on the teeth but it didn't give me alot of control, i also tried tighter gap and more teeth on the auger but that would happen to get clogged up while taking beans from the hopper. Maybe in the future i can try and also adjust the slope on the auger teeth but i feel like i have it at a comfortable and usable stage right now

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#18: Post by hazeleyes »

What an absolutely wonderful project! Bravo!

Agajohn (original poster)

#19: Post by Agajohn (original poster) »

thank you!

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BaristaBoy E61

#20: Post by BaristaBoy E61 »

Very cool!

Why do I see an automatic tamper in your future?
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