Manual machining still possible?

[MartinC]

Hello all,

I am planning to convert my SX4 mill, but as I have little time, it will be quite a while until I can complete it (years, I think). For starters, as I don't like the Sieg factory powerfeed (I already modified), I'd convert the X axis to ball spindle plus AC servo.
Would it be possible to use an Acorn controller as step generator for manual milling? Mainly there are two types of motion one would need: Jogging (Handwheel with selectable step size and/or joystick with progressive speed) and constant feed for milling (5 - 200 mm/s for example).

If this would be possible, it would save me building my own step generator for manual milling (with one axis converted). Also, what about manual milling when you have a working CNC system? Is this still possible or is it always G code entry?

Thanks! Martin

[suntravel]

Sure you can use Acorn for manual milling also, with the WMPG handwheel, MPGs on the USB BOB or jogging with VCP/WMPG/USB BOB.

Whatever you want, but with more than a single straight move, Intercon is way faster.

Uwe

[MartinC]

USB BOB looks nice!
What about connecting an analog joystick for jogging?

[suntravel]

USB BOB looks nice!
What about connecting an analog joystick for jogging?

viewtopic.php?f=57&p=96998#p96998

Uwe

[MartinC]

As I understand it, short answer is "no"
Long answer is: You can use a microcontroller to read the analog joystick values and convert them to quadrature signals you connect at the BOB handwheel inputs? (bonus: add handwheel inputs)
Sounds like a feature request @centroid.
I really liked the jogging feature with my "FB2" X powerfeed https://forum.zerspanungsbude.net/viewt ... 89#p607069, I think I used it more than the hand wheel. The key is a progressive characteristic, slow feed starts at 10 um/s with the motor going full steam ahead with the controller pushed to the limit.

Martin

[tblough]

It depends on what you call manual milling. Acorn is an open loop system so if you manually move an axis via handwheels, the machine will loose position. If you mean "manually" with a pulse generator, then yes you can with Acorn.

You'll need to move up to an Acorn6, AlllIn1DC, Oak, or Hickory to have true manual movement.

[RogDC]

As I understand it, short answer is "no"
Long answer is: You can use a microcontroller to read the analog joystick values and convert them to quadrature signals you connect at the BOB handwheel inputs? (bonus: add handwheel inputs)
Sounds like a feature request @centroid.
I really liked the jogging feature with my "FB2" X powerfeed https://forum.zerspanungsbude.net/viewt ... 89#p607069, I think I used it more than the hand wheel. The key is a progressive characteristic, slow feed starts at 10 um/s with the motor going full steam ahead with the controller pushed to the limit.

Martin

The BOB can accept inputs to use 2 way, 4-way, or 8-way joysticks ( momentary switches ) for jogging.

The MPG wheel connects to the MPG inputs which require a quadrature A/B input.

The micro-controller converts the analog signal from the analog joystick to a variable quadrature output to the MPG inputs.

[MartinC]

With "handwheel" I meant the digital encoder ones (typically 100 increments/rev, quadrature output), I guess you'd call them MPG?
What do you mean with "true manual movement"? I thought about an Acorn 6 anyway to be on the safe side (particularly after Uwe was advertising his 5 axis build), but I was not aware the there were other features like for manual moves?

BTW (not really related) you write it's open loop... I guess that's fine as I'd use closed loop servos (also as Uwe used lately). But as I have glass scales anyway on all axes (currently connected to a Aikron DRO), can they be connected also (maybe for position correction or for reference mark readout)?

[MartinC]

The micro-controller converts the analog signal from the analog joystick to a variable quadrature output to the MPG inputs.

Yes, that's how I understood it.
For that reason feature suggestion for centroid: Analog inputs for jogging.
I could implement that in a microcontroller (I do things like that for a living and still consider to design a 3 axis pulse generator - non-CNC), but rather buy something that works out of the box.

[WesM]

So, I have been thinking about a little side project that might be kinda in line with what you are trying to do. Essentially using the keyboard shortcuts in CNC 12 to simulate manual control using a macro keypad. Early on I know Marty showcased an X keys product that could do something like this.

For joystick control, you could solder a 4 way joystick outputs to four keys of the macro keypad. Then remap each of those 4 keys to up arrow, down arrow, left and right arrow. Hypothetically that should give you a pretty easy way of implementing joystick control. Nothing to stop you from doing this while the spindle is running to do manual milling.

I'm still turning the idea over in my head. Here are a few resources I have dug up that might be useful if you are interested in the project.

https://www.autohotkey.com/docs/v1/misc/Remap.htm

CNC12_keyboard_control_shortcut_legend.pdf

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