Inconsistent values from Versaprobe

Thanks for your reply!

Indeed there is something clearly incorrect. I'm not sure that it's in code or documentation or a combination of both.

I've tried numerous times to fix this without success. I think that it goes without saying that if it's not working properly,
it should probably be removed. It's very annoying.

I was reading the qr_auto_probe_tool.ngc code and this line:

#<calculated_offset> = [#<touch_result> - #<_hal[qtversaprobe.probeheight]> + #<_hal[qtversaprobe.blockheight]>]

Appears that the tool length, #<calculated_offset>, should equal the distance between the probe length and the loaded tool length. It is saved using

G10 L1 P#<tool> Z[#<calculated_offset>]

Which would indicate the length of the tool "should" be the difference between the probe length and the loaded tool length. We can assume the #<youch_result> as zero if we reprobe the probe...I think.

However, I get -70.(Something) For my probe length and -90.(something) For my tool length when the tool is shorter than the probe. At least in the tool table.

I think it would work better if the probe touched off and then, instead of "work piece height" which may or may not be G5? Z0, we should just be instructed to probe the Z0 point and set the offset between the tool setter and Z0 as a constant. Then just add that offset to the probe height and be done with it.

I believe the coding to include block height in every calculation is unnecessary and can cause errors. Plus, and I realize it's not Python, but the code could be more readable if there was a single constant offset then just amending the new tool length by that offset.

I may well be way off base here, because I am new and the code is different than what I am used to. But, I think the height setting could be simplified a bit. Just my opinion. Not trying to step on anyone's toes because it's obvious they put a lot of work into it already.

I have done some more investigating.

When I run the initial setup to probe the tool setter and the workpiece, I get
PROBE HT -55.990
BLOCK HT -70.610

Which would indicate the workpiece is 14.62mm below the toolsetter plane.

When I do a T1M6 (without physically changing the probe out) it errors as previously described.

If I move the machine manually to the workpiece height, I get Z70.610 in G54 coordinates. Notably, T1 now has an offset of -70.610 in the tool table.

It seems that, in G54 coordinates, the workpiece top should be Z0.

Perhaps the key is to probe the workpiece and set G54 Z(probe length) before making a tool change...?

Edit:

I am not sure what I did, other than put an M1 before the final return to the previous point.

Here's where I discovered an issue.

If the new tool is long enough to cause the return to point (in G54) to be out of bounds (in G53) it errors just the same.

So, there needs to be some logic that checks if the previously saved tool position will put the machine out of limits. Then, I think there should be a "Z SAFE TRAVEL" variable which the user can set as a minimum height to travel on during the tool change. This would account for the Z0 position not being the same height as the top of the workpiece.
Then, the logic checks to see if the tool tip is between G53 Z(Max) and Z SAFE TRAVEL. If so, move to the XY position at whatever Z height it's currently at. If not, move to Z SAFE TRAVEL then to XY.

I suppose the 'Z_MAX_CLEAR' parameter in the ini is supposed to do that, but it seems counterintuitive to be forced to change it for every new setup.

Of course, if I had a mill with more than 120mm Z Travel, that would probably help...

Well, I think I made it work by simply commenting out the very last move in the auto tool probe ngc.

My rationale for this:

Any post processor should have a move to the proper Z height after a tool change, unless there are very special circumstances. Thus, the return to the previous position in XY is good, while returning to Z is unnecessary, since the next line in the gcode should take it to whatever safe height was chosen in CAM.

So, my setup is such that all the auto tool probe Z clearing moves are at G53Z0 which is the maximum height of physical travel.

I do the initial offset measurement before starting a program,which measures the tool setter and then the top of the work piece. Since my workpiece top is at Z0, I just set it when the probe finishes probing. Then find XY0 and set that 
Next, remove the probe and shout "Fire in the Hole!" Because that makes you look cool to onlookers when pushing cycle start.

From there, the tool change to initial tool works fine. Then, the next tool change which used to error out since the tool was much longer just stays at max travel until the nc code takes over again.

So, give that a try. Just comment put the final Z move and see if that fixes things.

So that everyone is on the same page, would you mind providing the filename and
the exact line to comment, please?

Thanks in advance.