Spindle Interference

[Pointy]

Hi,

I haven't been around here in a long time, and to be honest I haven't used my crappy old upgraded (http://www.mycncuk.com/threads/7193-CNC-3020-Enclosure-Upgrade#post55250) CNC3020 in ages. Anyway I had a little job to do, so last night i went and fired it up, everything seemed to be working ok until I turned the spindle on, then the Y axis started moving about on it's own.

I have tried a few things but not sure where to go from here...



Swapped the axis cables at the back of the panel, and it was still the motor plugged into the y stepper driver.
Swapped the stepper controllers over and still the Y Axis.
Swapped the data cables on the BOB, still the Y axis
Rerouted spindle wires as far away from anything else as possible.


In case it's relevant the Y axis always seems to move in a positive direction.

Regards,

Les

[Rye]

Not sure if this is the same issue, but on my 6040, if earth cable isn't attached to the frame, the axis will go haywire during a job. Could it be a similar problem?

[Pointy]

Not sure if this is the same issue, but on my 6040, if earth cable isn't attached to the frame, the axis will go haywire during a job. Could it be a similar problem?


Thanks for the reply, I did already try that. It has worked fine for a year or so as it is and it has me a bit stumped now.

A couple of more things...



Hooking the bench supply up to the spindle and running it at 30v does not cause any movement.
Swapping the motor pins in MACH3, still always moves the Y axis.
Replaced the connector on the Y axis stepper driver.


I would have thought if it were a wiring issue, the axis that is moving would change when I change settings/connections. why is it always the Y axis???

The spindle and speed controller look exactly like this (http://www.aliexpress.com/item/USA-E240-CNC-200W-Spindle-Motor-Mount-Bracket-360W-Power-supply-and-power-supply-control/698475232.html?spm=2114.30010308.3.18.lnw2vV&ws_ab_test=searchweb201556_0,searchweb201602_2_100 57_10056_10055_10037_10049_301_10059_10058_10032_1 0017_405_404_10060_10061_10062_412,searchweb201603 _2&btsid=040449b7-4d95-434b-a440-a3597d025005). I did notice that part of the case is broken around one of the brushes, maybe that is causing excess noise?

Regards,

Les

[ptjw7uk]

If it is always the same axis I would suspect the lay of the wiring or an earth fault on that axis!

Peter

[Pointy]

If it is always the same axis I would suspect the lay of the wiring or an earth fault on that axis!

Peter

Thanks Peter but it can't be because of my tests above but.....

Last night I had a light bulb moment all because of one sentence I read why googling for answers...


If the dros in Mach are not changing then Mach is not telling it to move. It sounds like your picking up noise.

I suddenly realised because in my case the dro is changing, it can't be noise on the Motors, or BOB. Mach3 must think it is getting some keyboard input! The spindle is either causing some interference on the wireless keyboard or my HID controller.

Yes, you guessed it, my HID controller is the problem! This morning I went out and tried the spindle without it plugged in and there was NO movement of the Y axis. So now I know what the problem is, I just have to figure out why.

The HID controller is just a very simple single sided home milled PCB...

18981

18982

I am thinking it's either interference on the USB or my board/wiring. I am guessing the latter and would assume if I disconnect the joysticks and it's the former I would still get movement.

I could maybe fix it in the code by increasing the bounce time on the inputs (currently set to 10ms), but it would be nicely to identify the underlying hardware problem.

At least I have some direction now.

Regards,

Les

[Pointy]

After I bit more investigation, I noticed the spindle pot wires were right next to the joystick wires and simply moving them has cured the problem. I don't know if it's a sign of problem with the speed controller or just the fact the the spindle has got noisier but at least it's cured for the moment.

Regards,

Les