3D printed bean doser

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#1: Post by Kran »

Because... why not?

To ease the monotony of filling my bean vaults I thought I'd make a home version of a bean doser. This is the mech version that I fired up to test the form factor and work out fitment issues etc. Knob on back spins an auger, set on two skate bearings, and doses beans out of the hopper. In hindsight, if the end goal was a mechanical device I would put the knob on the front for ease of use. This, however, is just a prototype for an electronic version which will be driven with a stepper motor and have an integrated load cell scale...

For the 3D printing crowd out there, The main body is printed out of Proto Pasta matte fiber HTPLA. First time I've used this filament and I have to say it rocks. Front and end caps and mini, which hold the bearings and are friction fit into the body, are made from NinjaTek Cheetah to provide the flex I needed for a tight friction fit. Mini hopper is also made out of Cheetah and was initially designed to fit an OE mini hopper. I ended up preferring the all black aesthetic so I'll likely redesign the hopper for the electronic version.


#2: Post by I.Fix.Jura »

Thermal plastics for 3D printing is not stable, which means it will off gas and break down very easy. So I'd be very cautious to let it touch my food...

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#3: Post by JR_Germantown »

Unless I'm missing something, that's a hopper -- not a doser.

Edit: Oops, I see now.



#4: Post by Afiwrx »

Would love to try it out, do you have plans?

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#5: Post by tcaton »

This is interesting. I've been bouncing the same idea around for a while, but I've been approaching it from the other end: I have a load cell hooked up to an Arduino, and have played around with calibration & measuring latencies from the load cell (I have also a motor controller, but haven't hooked it up yet). The fabrication of physical doser is what limits me. I was planning on frankensteining something from wood and some robot parts from servocity, but haven't gotten that far. By the time I'm done, Baratza will probably have a refined retail model for less than the cost of my parts.

WIsh I had access to a 3D printer & skills to make plans for it. Is the auger 3D printed as well, or is it an OTS part?

Kran (original poster)

#6: Post by Kran (original poster) »

The auger is also printed because I had to size it correctly for the body and make the couplings that mount to the bearings.

It's a lot of: design, wait for print, fit, change by 1mm because it was too tight or too loose and then repeat.