In-line opensource joystick

[HuFlungDung]

I'm not sure if you guys are talking about machining or simply moving the axis, without the PC running, with a joystick.

Why bother? Is not jog mode within the cnc interface adequate for "manual machining"?

It usually pays to plan your moves (i., write a program first) rather than making it up as you go (teach mode).

[ESjaavik]

I primarily want the first, so I can do simple operations without the PC. The keyboard does not survive long in this environment, and I don't like those completely flat, membrane-button industrial keyboards at all.

Or maybe it's just because I miss the handwheels, or that I think it would look cool with more buttons and a joystick. Maybe I should look for a good shrink?

You're probably right Hu. And it is a good way to practice coding. Then if I get good and fast, I might control my model airplane using G-code too!

[mvaughn]

My original thinking was to use a joystick to get the cutting tool into position. The keyboard is a little awkward and cumbersome.

I have no interest in doing any manual machining with a joystick.

[pminmo]

mvaughn,
What kind of control electronics are you using?

Phil

[HuFlungDung]

Mvaughn,

If you want to use the joystick to position the cutting tool, or to do tool length offsets and work offsets (eventually), then you'll need to have the cnc controller running while you do this. I was confused because your earlier choice of "option 2" indicated otherwise.

There are gcodes available to get your machine from the home position into the workpiece's coordinate system, without turning off the cnc

I like the idea of a joystick for jogging, but I'm not sure how precise you could be with it. When you're setting up a tool length offset for a $250 thread mill, the last thing you want is "rough jogging" with a joystick You would need a way to change the resolution of the joystick "on the fly" so you could get down to very low jogging speeds, then switch back to very high jogging speeds. I think that the pulse generator concept is ideal for this type of precision jogging.

A joystick would be ideal for moving a robot arm, a motion that is less cut and dried. But on a regular cnc, jog buttons are practically as handy for rough jogging. Just IMO.

[ynneb]

Originally Posted by mvaughn My original thinking was to use a joystick to get the cutting tool into position. The keyboard is a little awkward and cumbersome. I have no interest in doing any manual machining with a joystick.

I also delayed in posting an answer because I thought you wanted to do work independant of a computer.
You can buy a PC game pad, similar to what you might get with a playstation.
If using a program like Mach2 you can use the keygrabber to asign functions to all the buttons on the gamepad.

So for instance you wanted to jog the machine to a corner of your work-piece
and then set it to zero, you could have a button asigned to set all axis to zero. Is this what you were hoping to do?

The game pads are very cheap. About 15 bucks. They plug in using the usb port.

You may have noticed the current thread about making a pendant. In reality it will be a gamepad, but set out more to suit a cnc machine, and have more buttons for more features.

Have I understood your question?

This one below is a cordless version that I have thought to use. In actual fact I have emailed the company to see if they would sell just the componentry so that I could remount it into a custom designed pendant control. This way it would be easy to build and alow easier identification of all the buttons.

[pminmo]

The only thing I see wrong with the gamepad approach, is the computer has to be on. What if you just want to jog the machine without the computer. (why I don't know)

Phil

[ynneb]

Originally Posted by pminmo The only thing I see wrong with the gamepad approach, is the computer has to be on. What if you just want to jog the machine without the computer. (why I don't know) Phil

He he, I dont know why either, but I have a manual jogger for when my machine is swithed off. I call it an arm.

EDIT:
I guess my only concern with the cordless gamepad is the rare possibility of a stray signal actuating the machine independantly. I dont know if the signal is so encrypted that the chances of that are neglegable or not ? Or if it is infrared, line of sight control.

[lucas]

Just joined cnczone and this is my first post.

For those of you who want a manual step/dir control:
I made one using only one potentiometer, it was intended to test controllers and perform basic stepper motor positioning.
The circuit uses two 8 pin chips: a 555 pulse generater and LM393.
Operation is very simple: center position of the potentiometer is stop, turning the pot slightly to the left will run the motor at slow speed, turning further increases the speed.
Turning the pot from the center to the right does the same but the motor runs in the other direction.

I have a schematic but it needs polishing before upload, any interest?

[mvaughn]

I'm interested. This sounds like a handy device.

[dwwright]

I don't know if Mach2 has any keyboard jog control, but I had a post on some free software that does joystick to keyboard mapping. The post is here:

http://www.cnczone.com/forums/showthread.php?t=7913

[lucas]

Schematic is here:
http://users.skynet.be/sky50985/CNC/stepctrl.pdf

The timing ranges from approx. 10Hz to 1kHz but can be modified by changing the value of the 1µ cap.

I also have a PCB layout but that needs polishing too...
Will try to do that this evening.

Questions and suggestions for improvement are welcome.