We want to realize for our school project a cheap and simple solution to control a band saw for cutting the trees (trunk) more comfortable with a RaspBerryPi.
We need two motors (each 30Nm) for this task.
One motor is for the thickness of wooden boards for about 30mm (adjustable 1mm to about 600mm, in 1mm steps). And a second motor for the automatic feed of the band saw (with adjustable speed and a limit switch or setting on the start and endpoint).
We also need a display and buttons (or Touchscreen) for the speed of the movement and to choose the thickness. Also the thickness of the band saw blade has to be taken into account. So when it cuts the first layer , then it should drive the Saw up with the next Layer (thickness) etc. etc!
I would be really happy if you could help me develop this project in a cheap way. And how can I connect a 30Nm Motor to the raspberry?
Is this possible with the Raspberry Pi CNC Board? Do we need the CNC Board Pololu Sockets or the DRV8825 Schrittmotortreiber for this?
We would be very grateful if you can help us with the following questions.
Dear all,
your project sounds very interesting and thanks for opening a topic. 
I’ve still checked out Google and concerning the stepper motor, you will need a motor with gearbox. In case of using a NEMA23 you will have around 3N.m torque and a power consumption of 3A per winding.
I would recommend stepperonline.com - The quality is very good and the products are very affordable.
Concerning motor driver / H-Bridges you can just run < NEMA17 (max 1.7A / winding) with an A4988 or DRV8825 everything which is bigger have to be connected to an external driver like: Treiber : Digitaler Schrittmotortreiber 1.0-3.2A 18-30VDC ...
Its very easy to get it connected to a a Raspberry Pi CNC head or any other controller.
To connect an external Driver to the RPI CNC HAT: https://mybotshop.de/raspberry-Pi-CNC-Board you need the external Driver Board as well: Protoneer CNC External Driver Socket | MYBOTSHOP.DE, 9,00 €
Concerning Software it’s a little bit more tricky, the problem is, most CNC control interfaces like bCNC are made for autonomous CNC Milling machines
As you can see above, every control interface has it’s own manual control with which you can move the axis, but most probably you have to write your own GUI or write your own Gcodes, which is more easier - Example below:
Anfahren der Home-Position X=0, Y=0, Z=0
N10 G01 X0 Y0 Z0
Hoping this helps!
Hi,
lot’s of thanks for your answer!! But I am not sure, if your solution is strong enough. I thought about 30Nm motors. Here you can see a picture from the band saw.
