Gsender cncjs Bitsetter probing always off by +3mm

I just set up Gsender on my shapeoko to make use of a digital probe, but my Bitsetter is always adding 3mm to the Z height every time I add a new tool and go to the previously established Z zero. It was working perfectly fine in carbide motion. These are the macros I’m using: CNCjs-Macros/C3D_BitSetter at master · cncjs/CNCjs-Macros · GitHub

I’ve checked the z travel and it’s not an issue with steps/mm, if I tell the cnc to go -5mm in z it goes exactly -5mm measured with calipers. I originally thought it was because I sped up the probing feedrate to match the carbide motion one, but even after I recopied the code with no changes other than putting in the probe location, it still offsets the z by 3mm. Could it be something with the limit switches?

Edit: I tried using the non Carbide3D version of the offset probe and toolchange macro by neilferreri but the same thing is happening.

It shouldn’t be the limit switches. It should be staying (%SAFE_HEIGHT = -10) away from the limit.

At any time is the Z axis hitting it’s lower limit?

How are you setting the workpiece zero? If it’s also with a probe, try setting zero manually & then changing tool and checking it.

You should be able to watch the Z value in the DRO as the macro is executing. During the initial macro it will pause after the 3rd touch on the bitsetter. Note the Z value.
During the toolchange macro it should change the Z value to that same value from the initial macro. If it doesn’t pause long enough to read, you could add a pause M0 before the last G91 in both macros.

At any time is the Z axis hitting it’s lower limit?

No, I’ve still got over an inch at both the probe and where I’m zeroing Z

How are you setting the workpiece zero?

Manually with a tool and a piece of paper, and then pressing Zero Z in Gsender

During the initial macro it will pause after the 3rd touch on the bitsetter. Note the Z value.

This may be part of the problem, I’m getting different final Z values with different tool lengths, the first one -95.17 and then -101.23 when I change the tool length. The weird thing is however that when I go back to reference the previous zero point, it always says the tool is 3mm lower than is actually is, both with a tool change and even if I keep the same tool when running the macro to probe a new tool.

I booted up Carbide motion again and it works completely normally on there.

I completely reset the machine through Carbide Motion and deleted and set up the macros again in Gsender and the problem appears to be fixed, although I’m still not sure what caused it.

As a side question, is it fine to set the initial z probing rate from 200 mm/s to 450mm/s considering that CM uses 500 mm/s? I’m assuming that it wouldn’t result in a difference in accuracy considering that it uses the slower secondary probing cycle to establish the offset.

Also, is there a difference to using the New_tool macro vs just using the Initial_tool every time to do a manual tool change? There’s also the Precision_Toolchange macro that looks to be about the same thing, can I just simplify things and use that macro for all tool changes?

Thanks

I would think if CM uses 450, then it’s ok for the gsender macros as well.
Still use the slower speed for the 2nd touch. Looks like the gsender macro does 3 touches, where the CM macro only does 2. We’d have to ask Neil why he did that.

The new tool macro records the bitsetter position with the first tool.
The change tool macro goes to the bitsetter, and then changes the current position (or Z zero) to the saved position from the initial macro.
The Precision Toolchange macro measures the current tool, let’s you change tool, then measures the new tool, then changes the Z zero to match the previous tool. So as long as you set the Z zero with the first tool you could just use this macro for all toolchanges.

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I would like to try gSender but am not clear if it is pain to switch back and forth between that and CM. Do you have to resend the config each time?

Note that the lip at the bottom of the BitZero is 3mm in height and there are two different ways to position it.

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The setup for gsender is really simple, you just connect to it and it automatically takes the settings and parameters from CM. You don’t need to do anything if you want to switch back, just open up CM and it works as normal.

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I originally thought that the software was accounting for a bit zero offset when I was using bitsetter but it fixed itself after doing a full reset and using the exact same macro.

Fired up my machine again and it happened again, only now it’s giving me a way higher offset. After probing a tool, zeroing, probing a new tool and asking it to return to Z0, it thinks z zero is somewhere close to the top end of Z travel, way higher than what the actual z zero is.

This may or may not be correlated, but the z glitch seems to be happening after I use the Hole_center macro with a digital probe that is plugged into the Bitzero slot, but I’m not sure.
When I probe z, it seems to be resetting the z probe to around -82mm instead of 0.

Here’s my procedure for testing:
Turn on machine, home, run initial probing macro with tool, set zero on workpiece, run load new tool workpiece, tell the machine to go back to the initial set zero.

I tried using the precision tool change macro and all it does is repeat the probing process in a loop. When I cancel, it just soft locks the machine.
I again went back to carbide motion, this time without resetting the machine, and it works normally.

Did some more testing, it looks like the circle center probing is somehow interfering with the z probe.
Every time I probe z after I use the hole center macro, it assigns a a seemingly random but consisent between resets z offset.

I can “reset” the z probe by connecting to CM and reconnecting to Gsender but every time I use the circle center macro with a digital probe it messes the Z probing up again. Does anyone know why this is happening and how to fix it? All of the code is copied from the cncjs macos page by neilferreri and all my software is up to date.

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