qtdragon - probing issues

cmorley wrote:

Ok I can see the problem in the code.
The underlying probe routines don't even get separate xy/z max travel lengths.

It will take me a while to tease out the fix though.

Yeh, I've been digging but don't understand the flow, but yes if its  a straight down probe,  probe_down() needs to receive the contents of lineEdit_max_z and you are not saving that anywhere.

It is pretty important becsaue stright down is the dangerous one so people wil like to kep the distance low say 2mm so the probe does not get damaged.

A note on useage: extra depth need to be set to say 1-2-3mm becasue otherwise we seem to probe at the top of the material and we need to be lower than that in case there is a chamfer on th edop of the material.

If you really wanted to be cool, and I need to think about it a bit more, if there was a setting to probe straight down and then Probe XY in one move it would be great. I think that needs to be  done from the corner probe (eg call straight down first, then do corner). eg we if had a Probe for height first flag to enbale that feature.

PS you might regret my help before long. I'm good at reviewing applications and seeing opportunities to map to the user experience! 

(despite my best intentions, I have bent my spare probe already. Just make sure its plugged in before probing!)
 

Versa probe doesn't separate max travel for xy/z - I suppose they want you to set it each time if you want it different.
They both use the same underlying code for probing - so it's complicated to make changes.

I test with a plastic tube on my probe, because I did the same sort of thing.
We should probably add a 'probe connected' HAL pin to linuxcnc.

Big changes to probing will need to go to master. It would be nice to get a consensus from the few people that use probing.

But no bugs and good docs is the highest priority for 2.9.
Thank you for the help.

Versa seemed to work well except that the straight down probing was on another tab and It wasn't adjacent to the corner probing. That is the biggest feature basic probe adds, it's all on one panel.

I have yet to master inside probing of a hole without errors on either. I'm pretty sure there must be some non probe moves inside the hole which makes no sense. I'll try with a hole bigger than 10mm but it should be able to probe holes much smaller than that!

I guess one "fix" for now would be to remove the z axis field and edit the name of the other for 2.9 but a better solution would be to enhance versa to agree.

I did think about having a probe connected signal but could not think of a way to implement it. In any case the lights on the probe tell it all if you think to look!
 

I think I have this working..was easier then I thought. If I make a test branch tonight could you test at your convenience?

Yeh, let me know what branch to checkout when you are ready

Here it is:

github.com/LinuxCNC/linuxcnc/pull/2469

Great,  I'll give it a go tomorrow some time. I just got on on Friday night and am having a beer
Can you give me the command to checkout that link please? I'm only good with the basics in git!

git pull
git checkout qtvcp_probe_max_z_fix

should do it

Ok Versby seems unchanged from prior behaviour

Basic Probe incorrectly finishes at z clearance + extra depth

See attached image Z is at 13mm when it should (and was previously) be 10mm
 
You need the extra depth becasue if you probe to surface and finishes at Z10
on an XY corner probe the probe only decend to the surface height before probing for the material. Adding extra depth ensures the probe contacts the edge instead of potentially skimming over the top.

Because each probe routine is a python procedure, It might be possible to add a checkbox to basic probe "Probe to height first"
If set,  a corner or edge probe could probe for the height before probing for X & Y. 
That would let you zero the machine in one step (and is consistent with a normal workflow)
That would be cool!
 

So the only change I did was separate xy and z max probe distance. You can have them at different lengths.
This doesn't have anything to do with finish position.
Can you confirm that max Z is being honoured now

finish depth:
I see in the code, extra depth is always added to clearance, but when down probing I think it shouldn't. extra depth does make sense when down probing.
extra depth is to get below chamfers etc when side probing.

Does that sound right?