[Smackre]

Hello,

Looking for recommendation on controlling a stepper motor. Normal Nema 34 1841 oz. Stepper connected to a ball-screw. It will be feeding a table that is on a tile saw for cutting tile.

Wanting to have three limits controlling the stroke.
Limit #1 Loading position
Limit #2 Cutting position
Limit #3 End of Cut

Would like it to start at the loading position and feed to the Cutting position at fast speed. Once it hits the limit for Cutting position to slow down to cutting speed. Very slow feed. Something around 1" a min. Feed till it its at the end of the cut limit and reverse at rapid speed and go back to Loading Limit.

What is the best way to do something like this?

Thanks,

[Louis_Cannell]

Its still going to be CNC just a single axis CNC, control can be by any suitable software and requires very simple code, Mach3 would be simple to set up a couple of limit switches and old 32 bit pc with windows XP and a parallel port. a power supply, breakout board and driver would be the other main requirements.

[Smackre]

I kinda want to stay away from CNC control. Was thinking something like this.

https://www.youtube.com/watch?v=RakXequOrSY

Just unsure about programming it.

[Toinvd]

Arduino is a good solution for such a easy CNC job. Yes even with a Arduino it's CNC.
Start reading a bit about the Arduino, and connect the stuff together on the table without the ball-screw.
This way you can make the program without risk for the big machine.
Arduino has a good library for stepper driving and enough input capable to connect your 3 position switches and a start and stop button

[CitizenOfDreams]

Arduino has a good library for stepper driving and enough input capable to connect your 3 position switches and a start and stop button

The way I see this project, it just needs one home switch. The three working positions - "loading", "start of cut" and "end of cut" would be programmed in software.

[Louis_Cannell]

Programming the CNC version would involve
G00 Y0 (start point)
G00 Y100 (Edge of cut)
G01 Y1000 F25 (cut 900mm at 25mm per minute)
G00 Y0 (Return to start)

[Smackre]

CitizenofDream

I like the idea of having limits for Start of Cut and End of cut. Because if I change materials all I need to do is move the limits. And not change anything in the programming. With the Arduino is there a way to use a potentiometers to control the cutting speed. Program the rapid speed and pot for cutting speed. As I may need different speeds for different materials.

[ger21]

Try a PLC like a Cubloc

[Smackre]

Ger21 do you have any experiance with the Cubloc.

So with the Cubloc and the Arduino you still have a stepper controller right? So I would need a PSU,Stepper Motor,Ardunino or Cubloc and a Stepper controller correct?

[ger21]

Controller is not the right term. You need a stepper drive to run the stepper motor.

And no, I haven't used one myself.

[jfong]

Take a look at the Geckodrive gm215 programmable stepper driver. Has three inputs for your limit switches. Although I think you need more inputs for safety such as emergency stop, run etc.

http://www.geckodrive.com/gm215-step...ontroller.html

[CitizenOfDreams]

CitizenofDream

I like the idea of having limits for Start of Cut and End of cut. Because if I change materials all I need to do is move the limits. And not change anything in the programming. With the Arduino is there a way to use a potentiometers to control the cutting speed. Program the rapid speed and pot for cutting speed. As I may need different speeds for different materials.

If you are planning to go through the effort of programming the Arduino, you might as well add an LCD display and a keypad - so you could change your rates and limits with a few keystrokes, save presets for common materials etc. It would be much more elegant than moving the limit switches physically. And yes, Arduino has analog inputs which you can connect potentiometers to.

On the other hand, if you have never dealt with microcontrollers and software programming before, it could be quite a steep learning curve. If you need your machine up and running quick, just use an old PC and a copy of Mach3.

[James Newton]

Just to sort of summarize what others have said: From the "top" down there is:
1. User interface
2. Motion control
3. Driver
4. Motor

Mach3, TurboCNC, EMC2, etc... provide 1 and 2. User interface AND motion control.

Pronterface, G-CODE sender, etc... provide 1. User Interface, and work with RAMPS/Marlin, GRBL, etc... which provide 2. Motion Control

Or... you can write a custom program for an Arduino (not that hard) to provide the Motion Control and use a pushbutton switch as the "User Interface". That's probably the lowest cost option, but needs custom programming.

In any case, you need a driver to drive the motor. I, of course, recommend my own THB6064AH driver (see link in signature) but the Geckodrive unit is certainly more powerful (also more expensive). For GOD sake, do NOT buy one of those cheap drivers from China like the TB6560!

And... before you do any of that, figure out what MOTOR you need first! Based on the torque required to push the saw. There is a link to help you estimate the needed size of the motor / driver from my signature.