[merlin777]

I want to test out the mechanics of my custom cnc machine before going any further. I want to check that the motors have enough torque and the way I've mounted them is suitable.

I have an x y axis which are a small milling table and a rotary axis which is a chuck on a rotary table.

I will remove the handwheels and use flexible shaft couplings on the spindles.

I only want to turn a motor enough to test my engineering with the stepper I will be using. I'm not ready to develop the electronics for the whole machine yet.

Is there a very cheap simple device that will turn a (nema 17) motor forward and reverse?

[rodw]

An Arduino and a Polou Driver and an example Arduino script will easily handle a NEMA 17.

[merlin777]

An Arduino and a Polou Driver and an example Arduino script will easily handle a NEMA 17.

Hi Rodw. Thanks for this but I just want to turn the motor. A motor driver board, arduino board, and programming is most of the way to a full setup. Surely there's something simpler?

[rodw]

I'm a software guy but the Pololu A4988 stepper controller and an Arduino will set you back less than $20 and you can drive it with 10-20 lines of code. Something like this example
https://forum.arduino.cc/index.php?topic=133894.0
Nothing like a full setup. That took me 200 lines of code.... but thats another story.

[Voltatek]

You need to give the specifications of your motors if you want us to help determine the best solution for your needs.


https://voltatek.ca

[merlin777]

You need to give the specifications of your motors if you want us to help determine the best solution for your needs.


https://voltatek.ca

Hi there. Here's the spec.

Description:
Motor type: Bipolar Stepper
Motor Length: 40mm
Phase Resistance: 1.5Ohm
Phase Inductance: 2.8mH
Detent Torque: 2.2N.cm
Rotor Inertia: 54g.cm2
Holding Torque: 40N.cm
Motor Weight: 280g
Step angle: 1.8 deg
Step angle accuracy: + - 5%(full step, not load)
Resistance accuracy: + - 10%
Inductance accuracy: + - 20%
Temperature rise: 80deg Max(rated current, 2 phase on)
Ambient temperature -----------20deg ~+50deg
Insulation resistance: 100M? Min, 500VDC
Insultion Strength--------500VAC for one minute

[merlin777]

So, just one of those tiny driver boards and an arduino? I dont need a shield for the arduio too?

How do you get the code onto the arduino?

[rodw]

So, just one of those tiny driver boards and an arduino? I dont need a shield for the arduio too?

How do you get the code onto the arduino?

You download and install the Arduino IDE environment, open the sketch (a text file) in the IDE, compile and download it with one mouse click.

[merlin777]

does the arduino connect to the pc via usb?

[rodw]

does the arduino connect to the pc via usb?

Yup.

Bear in mind that it might just be simpler to set up your CNC motion controller of choice at this stage and connect your motor to it even if nothing else is built.

[merlin777]

thats what I'm thinking. What's being suggested is virtually the whole electronics chain. I was holding out for a simple solution because I thought it wouldn't be that hard to apply some pulses to a motor.

[hfjbuis]

You download and install the Arduino IDE environment, open the sketch (a text file) in the IDE, compile and download it with one mouse click.

You find all the information for connecting, configuring and running a GRBL controller at this site.

https://github.com/gnea/grbl/wiki

[merlin777]

look what I found:

https://www.amazon.co.uk/POLOLU-3134...tor+Controller

[hfjbuis]

This could do the job, but cost about as much as an arduino and polulo shield, but still a nice product!

[merlin777]

This could do the job, but cost about as much as an arduino and polulo shield, but still a nice product!

It's not hugely expensive. I might save a lot of money by checking at this stage my mechanical engineering is sound and my choice of motor is appropriate.
But I think mainly it prevents me from having to jump ahead and learn a huge amount I'll need to know but now and all in one go. It's going to take weeks for me to properly learn the electronics stage before trying to tackle it safely and this way I don't get held up. It'll also be a good intro for me to practical stepper motor control and ultimately a handy little item for the future.
I'm already thinking of how I might use it in macro photography for stacking!

[merlin777]

If I get it working I'll write it up. Might even do a video.