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Inverting the Z axis for g-code

Ok, been working on getting my first run out of Fusion, through the F360 Boxzy post processor, into the Boxzy Interface, and out to a finished part on the plate. The problem i’m finding is that the Z in the gcode is coming out as negative integers but my configuration is set with Z-down being positive. There has to be a way to switch this somewhere in the chain from CAM to control, right? Right? I’ve seen this same question asked in several forums with zero reply, so either I’m asking the impossible or this is so bloody simple that I should figure it out? Tell me it isn’t that.


Update (12/25/2018)

I’ve finally found the time to come back around to this. My WCS isn’t the issue, it’s that my Z axis on my printer is backwards. Here’s a crapload of screen shots to prove it out to you so that hopefully I can get the right answer and have this machine working how it should.

Here’s the a shot of the CAM (I originally had the work WCS in the position you recommended prior to posting my question, so I decided to try the opposite this time ) -

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These are two shots of the simulation show solid tool paths for the part-

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And last here is the first bunch of g-code. Please note the z axis-

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When sent to the printer, the z axis moved away from the router instead of towards it.

So I switched the WCS BACK to the original one that I ran before asking this question - pic of the CAM set up, identical toolpaths as before except with the adjusted wcs and adjusted heights in the toolpaths themselves-

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Heres the g-code for this run -

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These were the post process parameters on both posts -

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Aaaaaaaand, finally, here’s my manual control showing that my z axis is backwards and I don’t have a handy button on my interface that switches it like I’ve seen in other photos

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Help would be appreciated, this is killing me

Answer this question I have this problem too

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1 Answer

Hi Aaron,

I believe I see where you're getting tripped up. The platform moves down for positive movement and up for negative movements. The arrows represent up for ( + ) increase distance, and down for ( - ) decrease distance. Imagine if you press up on a standard vertical mill, the head would move upwards, which is the same effect as the platform moving downwards, it increases the space between head and platform. The buttons are placed to follow a standard vertical mill button layout. If you would prefer the buttons reference the platforms movements specifically, rather than the relationship of the head to the platform, you can invert the arrows by going to Config -> Preferences. You can adjust many of the buttons there.

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That part is merely slightly annoying and easily compensated for, but it's my understanding that changing that configuration won't have any affect on how the printer reads the g-code- i.e. according to your answer, when Fusion out puts a -move, the platform should be moving up, but it's not. For example, in the first part of the g-code I included, line 10, 11, and 12 should have the platform move up to go from the start position, to the clearance position, then ramp into the cut. Instead it's moving down.


I direct messaged you


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Aaron will be eternally grateful.
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