Hi all!
I'm new here, so if this has already been discussed before then sorry, and please point me to the discussion topic.

I have a 1zpresso j-max grinder, and it's really good I love it, but I'm trying as a personal project to motorize it, but I'm not all that experienced with motors, there are multiple things to decide, like DC or AC? Should I look for a stepper motor or not? What are the specs of the motor, or how do I calculate the torque and RPM needed for the grinder? Do the burrs have any impact on the decision? Should I look for something that gives me those torque and RPM values, or I should aim for higher numbers to leave a margin for error and losses?

Sorry for the many questions but I'm just trying to make the best decision possible so that I get the best results from the grinder.

I'm also thinking of attaching an Arduino so that I can have some control for the speed (if advisable) and timer and such, would that affect the choice? Or I can pretty much attach that to any motor and get the same controls without problems?

Thank you!

The absolute easiest way is probably to buy a battery operated drill and an appropriate sized bit to drive the grinder if that's possible. Plenty of power and built in speed control. Once it works, you can probably cut off the handle and mount it in a nice box and simulate the trigger speed control with an Arduino.

Ira

I'm part way through a project to motorize a hand grinder myself. I'm using a stepper simply due to the ease of changing speed and rotation. The stepper has a 4:1 planetary gear box attached. What you should do is go through the older posts here where people motorized HG-1s. I learned a lot about spec etc. in those posts. Eventually, it'll come down to cost of supplies and final form factor.

Here's where I'm at. It grinds coarse but I need to re-design it a bit for a little more rigidity and will likely go to a larger stepper without the gear box.

ira wrote:The absolute easiest way is probably to buy a battery operated drill and an appropriate sized bit to drive the grinder if that's possible. Plenty of power and built in speed control. Once it works, you can probably cut off the handle and mount it in a nice box and simulate the trigger speed control with an Arduino.

Ira

Thank you. This can be a useful starting point, I may use one and then get a motor with the same specs as the one inside (or just tear it apart and use that), and then add the functionality I want later.

Kran wrote:I'm part way through a project to motorize a hand grinder myself. I'm using a stepper simply due to the ease of changing speed and rotation. The stepper has a 4:1 planetary gear box attached. What you should do is go through the older posts here where people motorized HG-1s. I learned a lot about spec etc. in those posts. Eventually, it'll come down to cost of supplies and final form factor.

Here's where I'm at. It grinds coarse but I need to re-design it a bit for a little more rigidity and will likely go to a larger stepper without the gear box.

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This is really helpful! Thank you, I'll look at the posts you mentioned and it will surely help me in my pursuit. Thanks a lot!

Kran wrote:I'm part way through a project to motorize a hand grinder myself. I'm using a stepper simply due to the ease of changing speed and rotation. The stepper has a 4:1 planetary gear box attached. What you should do is go through the older posts here where people motorized HG-1s. I learned a lot about spec etc. in those posts. Eventually, it'll come down to cost of supplies and final form factor.

Here's where I'm at. It grinds coarse but I need to re-design it a bit for a little more rigidity and will likely go to a larger stepper without the gear box.

image

Whoa that's awesome looking. Looks like you're using Lido 2/3 guts?

Would love to motorize my lido

A 500-people group improved their motorizing project and open-sourced their results.

Here is one of the samples:


They use 240W (120W is ok but less buffer) high torque motor to run the grinder so that it can grind espresso in heaviest grinder.

Interesting, can you please provide a link to the project?