Manual use of CNC machine

[slow-poke]

I often hear comments to the effect "I don't want CNC because I want to be able to use my machine manually.

So do I often. One does not preclude the other.

Images of manual controls for my lathe.

There are two rotary switches and a MPG.

- The MPG emulates the hand wheels, it's graduated in 100 "ticks"
- The first rotary switch, lets you select either: nothing, the X axis, the Z axis, or the compound axis
- The second rotary switch lets you select either: 0, 0.0001", 0.001", or 0.01" per tick

-Action video showing carriage moves with MPG (Z-axis) https://www.dropbox.com/scl/fi/vkkw...ey=k5ghuzzkk6mujk25axft44q8e&st=m2ldco40&dl=0

 

[slow-poke]

- The compound axis is actually performed in software using angleJog. angleJog simply calculates the correct X & Z ticks for the desired angle.
This has a couple of benefits:
1) the machine is much more rigid without the actual compound. This actually makes a significant improvement on this small 10" lathe
2) setting the angle is as simple as typing it in.

 

[PeterT]

That's pretty darn cool. Lets say you definitely did not want CNC but wanted your dial setup (more as a retrofit to a manual machine). Could it operate through a black box only or do you always require some kind of controller app running in the background?

 

[slow-poke]

That's pretty darn cool. Lets say you definitely did not want CNC but wanted your dial setup (more as a retrofit to a manual machine). Could it operate through a black box only or do you always require some kind of controller app running in the background?

You would need some sort of simple blackbox.

So many ways to do something like this.

Off the top of my head....

1) The MPG produces quadrature signals, a FlipFlop will convert those signals to step and direction (that's what the stepper or servo needs)
2) That step signal then needs to be scaled
3) The scaled signal then needs to routed to the correct servo.

Fairly trivial, could be done one small PCB

 

[Chipper5783]

Both my CNCs (lathe and mill), came that way from the factory with the capability for manual moves. I thought they all did.

I have three good running manual milling machines, I rarely use them (they each have features that other members of the family don’t: size, tilts, torque, attachments - whatever). But even for one off operations the CNC mill is the goto machine - like @slow-poke says.

The CNC machines have a jog feature that one can dial the speed on, or use the hand wheel - select which axis and what step size. Works great for quick cuts, drilling a hole etc. Obviously that gets old when you can just throw in a few lines of code or use the MDI (manual data input). However, slow-poke’s point is very valid, many CNC machines can be operated as manual machines.

 

[David]

I use the hand wheel on my CNC mill's pendant all the time as a 'manual' machine.

 

[slow-poke]

Both my CNCs (lathe and mill), came that way from the factory with the capability for manual moves. I thought they all did.

Go figure, I have never purchased or worked on a factory built CNC machine. I just convert my manual machines.

 

[slow-poke]

You would need some sort of simple blackbox.

So many ways to do something like this.

Off the top of my head....

1) The MPG produces quadrature signals, a FlipFlop will convert those signals to step and direction (that's what the stepper or servo needs)
2) That step signal then needs to be scaled
3) The scaled signal then needs to routed to the correct servo.

Fairly trivial, could be done one small PCB

If I did a blackbox controller, I would probably just use the cheapest smallest Arduino with NVRAM to store the scale factors and backlash values. Something < $10 that would fit in a off the shelf Hammond box.

Hammond 1591BSBK ABS Project Box Black by Hammond : Amazon.ca: Tools & Home Improvement

Hammond 1591BSBK ABS Project Box Black by Hammond : Amazon.ca: Tools & Home Improvement

www.amazon.ca

 

[slow-poke]

Mini / Type-C / Micro USB Nano 3.0 With the bootloader compatible Nano controller for arduino CH340 USB driver 16Mhz ATMEGA328P - AliExpress 502

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

 

[Susquatch]

You would need some sort of simple blackbox.

I use the hand wheel on my CNC mill's pendant all the time as a 'manual' machine.

Isn't it easier to just put a hand crank on the lead screw? Then you could call it manual cuz it really is.

 

[slow-poke]

I think some might be looking for an alternative to a conventional power feed.

Especially when an OTS power feed is not available for their machine, or:
- they want precise movement control
- they want backlash compensation
- compound movement without a compound