Multiple probes - different readings

[bhdavis]

I have two probes on the CNC now. One fixed in place (Probe #1) for the Rapidchange ATC and one portable (Probe #2) for locating the material surface location.

First, the portable probe is acting strange. It didn't used to act this way. When starting a project after picking up and measuring a tool on the tool rack with fixed probe #1 I'll move the bit over the material and set the portable probe (#2) there and do an M31 probe measurement. Almost every time the Z reading will be 2 to 3 inches above the material. It's almost like the height of the probe is not being used in the calculation even though it is in the macro. And then if follow up with a 2nd run of the M31 macro the measurement is dead on. Z0 is right at the top of my material. Every time. So a solution for this could theoretically be to set the M31 to automatically run twice. Not a great solution though. Especially as it will relate to the 2nd half of the problem.

Second, there is something strange going on in the relationship between the fixed probe (#1) and the portable probe (#2).

I can cycle between any of the 6 tools in the tool rack and they are repeatedly recorded correctly in the TOOL OFFSET list. However if my portable probe (#2) G53Z0 location were 5.5" above the table, it raises up 2" to 3" after a tool change. Again, all the tools are listed with proper measurement relationships in the tool list, its' just that the material surface location gets screwed up.

I didn't have the problem before I swapped out my 6 year old damaged C76 control for the new one. So I'm wondering if there might be a relationship there or if I might have gotten something out of whack in UCCNC during the month long repair process.

System is:

UCCNC 1.2111
Probe #1: Pin 12 - Port 2 - Active Low checked - Normally closed
Probel #2: Pin 10 - Port 2 - (2 different probes used with same results. One normally closed with Active Low checked and one normally open with Active Low NOT checked.

I'm attaching both my M31 macro for the portable probe #2 and my M931 macro for my fixed ATC probe #1. However I have tried other versions of my macros with the same results so am thinking they are not the problem.

AND I WILL ADD WHAT I JUST DISCOVERED. All this only happens if I touch down to my material with Probe #2. If I physically set the tip of the bit on the material and call that my Z0 point everything works as it should. So it looks like the problem is somehow with the portable probe #2.

Thanks,
BH

[bhdavis]

Well I've done some digging around and found a post that talks about using a G43 or G44 along with an H96 inserted into the M31 macro. I didn't understand what was being discussed but it seems to be related to using two probes in the same way as I'm doing.

Am I on the right track? Can someone enlighten me on this?

Thanks,
BH

[bhdavis]

Is this G44 group of lines in my M31 macro what is causing the problem? From what I've found online it would seem it should be G43. I can experiment with it in the morning.
Thanks,
BH

{
exec.Code("G44 H1"); // Load tool offset one, note the tool length is defined in the tools menu
while(exec.IsMoving()){}
exec.Wait(200);

double Zup = exec.GetZmachpos() + retractheight;

if(Zup > SafeZ)
{
Zup = SafeZ;
}

[ger21]

Yes, tool length offset should be G43, not G44. I think that will fix your problem.

[bhdavis]

Thank you Gerry. That did indeed solve the problem.
BH