Tool height sensor.

[Ollie78]

Hello

Just a quick question or two about tool length sensor issues.

I have the plate and crocodile clip sort which was working well then stopped working. UCCNC says something like the probe is active. I have had some advice saying its an earth/ interferance issue.
Not had time to sort it out but wondering if I used a switch type it might solve the problem.

I have seen this type https://www.sorotec.de/shop/Tool-Length-Sensor-Sorotec-Small-8mm.html

and these other ones
https://www.amazon.co.uk/Kehuashina-Z-Axis-Router-Setting-Milling/dp/B07FMGRKNJ/ref=sr_1_1?keywords=Kehuashina+CNC+Z-Axis+Router+Mill+Touch+Plate+Mach3+Tool+Setting+Pr obe+Milling&qid=1560520876&s=gateway&sr=8-1

Do these work on an actual switch rather than conduction through the probe, if so is this likely to avoid the problems of interference I am having by being a more positive on off, if you see what I mean.

£20 is worth it for not having to trouble shoot it.

Ollie

[EddyCurrent]

The Sorotec uses a switch without an earth connection but the amazon one uses the earthing method.

If these are to set "Z zero" then it looks like you would need to measure these to get the exact height at the point of switch activation.

[Ollie78]

Thanks Eddie

Currently I have just entered the thickness of the plate into UCCNC somewhere or other. So if I was to get the Sorotec one, I could measure it to the point it activates the switch and enter it in this same box.
Perhaps they supply the measurement with it ? Otherwise I suppose a bit of trial and error for the first set up then its done.

Do you think it would solve the interferance problem I am having?

Any other switch type ones recommended ?

Ollie

[EddyCurrent]

If it was my machine I would have to first find out what the original issue was with the probe.

[Ollie78]

If it was my machine I would have to first find out what the original issue was with the probe.

Well, I am trying to find out the issue with little success.


Today I cut two ferrite beads or rings or whatever they are called from the wire on an old xbox 360 controller. I disconnected both the wires to the probe and wrapped a section of each wire through and around each ferrite ring in the hope this may reduce interference as suggested to me.

To my initial delight the first time I tested it the touch probe worked as it should, so I thought it was fixed. A bit later I went to cut a small project and started to set the work zero`s attached the clip and clicked the auto z button, I was prompted to tap the plate on the bit which I did. The screen said it had registered the tap or something to that effect, then immediately the same pop up came on saying the probe is active.

Now after trying a few times I couldn`t make it work again (tried swapping wires over, restarting everything etc). The probe lights up the correct led on the diagnostic screen.
I noticed a flickering light on the diagnostic screen really quickly flickering off and on. It was PORT #2 01. Could this be what is causing my interference ? And what is it ?

So one step forward and two back.


Ollie

[erasma]

1.) What voltage are you using to do you probe setting? or is it just an open wire to the BOB?

2.) unplug your VFD or Spindle motor and try a few times to touch off

3.) check your voltage on the wire's of your probe setter see if there are any spikes or continuity happening




Well, I am trying to find out the issue with little success.


Today I cut two ferrite beads or rings or whatever they are called from the wire on an old xbox 360 controller. I disconnected both the wires to the probe and wrapped a section of each wire through and around each ferrite ring in the hope this may reduce interference as suggested to me.

To my initial delight the first time I tested it the touch probe worked as it should, so I thought it was fixed. A bit later I went to cut a small project and started to set the work zero`s attached the clip and clicked the auto z button, I was prompted to tap the plate on the bit which I did. The screen said it had registered the tap or something to that effect, then immediately the same pop up came on saying the probe is active.

Now after trying a few times I couldn`t make it work again (tried swapping wires over, restarting everything etc). The probe lights up the correct led on the diagnostic screen.
I noticed a flickering light on the diagnostic screen really quickly flickering off and on. It was PORT #2 01. Could this be what is causing my interference ? And what is it ?

So one step forward and two back.


Ollie

[EddyCurrent]

erasma,

Do you have any electrical knowledge or are you just clutching at straws ?

[erasma]

erasma,

Do you have any electrical knowledge or are you just clutching at straws ?

lots of straws - hope you help sort his problem out enjoy

Just for reference my home made CNC Machine - https://www.youtube.com/watch?v=jaxabBOKDG8

[Ollie78]

1.) What voltage are you using to do you probe setting? or is it just an open wire to the BOB?

2.) unplug your VFD or Spindle motor and try a few times to touch off

3.) check your voltage on the wire's of your probe setter see if there are any spikes or continuity happening

1- It is connected to ground on the BOB with one wire and one of the inputs (number 2 I think) I have tried switching the wires around to no difference in result.

2- I did try this before, again no difference. The VFD is not in the same control box and is grounded by its own plug.

3- I have not done this. However I can see that it must be working to a degree as the led indicator in the diagnostic screen of UCCNC is showing when I touch the probe to the bit.

I am thinking it could be when the stepper driver starts the Z axis moving that is causing the issue as it lets me begin the process and registers the first touch, then as soon as it should start moving towards the plate it freaks out and throws the error message.
I will have a look again next time I can spare a few minutes.

Thanks

Ollie

[erasma]

there are a few things one can try. I think it's either the probe or you have some emi which is causing the probe to register a touch. I use 12V on all my switches to avoid false inputs as the 3v & 5v are prone to have this in environments with large RF spikes "Plasama Arc & VFD,s"

1.) when your probe stops working and keeps saying it's connected un screw it from the BOB "MAKE SURE YOU CAN STOP YOUR MACHINE" try probe again you will need to stop the machine from crashing but that will at least give you an idea if the issue is with the probe and cable?

2.) take some twin core flex wire connect it into the pins your tool setter goes and touch off with the bare wires. you can do this manually holding the wires and just touching them together. you would need to touch then together twice as per your probe routine.

make sure you are confident you can stop your machine when doing this & take all bits out of your machine so that the spindle does not crash but rather the motor stalls if it does not stop in time.




1- It is connected to ground on the BOB with one wire and one of the inputs (number 2 I think) I have tried switching the wires around to no difference in result.

2- I did try this before, again no difference. The VFD is not in the same control box and is grounded by its own plug.

3- I have not done this. However I can see that it must be working to a degree as the led indicator in the diagnostic screen of UCCNC is showing when I touch the probe to the bit.

I am thinking it could be when the stepper driver starts the Z axis moving that is causing the issue as it lets me begin the process and registers the first touch, then as soon as it should start moving towards the plate it freaks out and throws the error message.
I will have a look again next time I can spare a few minutes.

Thanks

Ollie

[Ollie78]

Many thanks for the replies everyone.

I have however bought a switch based z height sensor. I got one from Sorotec but opted for the slightly bigger one with 14mm button.
It has immediately solved the problem, I wired it in and it showed up in the diagnostic screen when pushing the button.
I had to edit the m31 macro to active switch ( true mode )and do a few repeat tests to get the exact switch activation height after getting it close with a caliper.
Have used it quite a bit so far with no problems and very good accuracy.

I understand there is likely still some kind of electrical interference going on and one day I would like to go over everything and build a nice professional control box, but for now it works well and I can keep learning on this machine.


Ollie