What did I Miss?

So here is the deal, I have had some good success with designing parts in the Fusion 360, using the post processor, and sending the G code using UGS. However of the last few days I have seemed to screw something up and I can’t figure it out. I’m hoping its something stupid that I’ve overlooked that you guys can help me with.

I was in the process of making a cornhole set for a friend and i thought cutting out the legs on the XC would be an easy project. I designed the parts in Fusion 360 with no issues, exported the G Code and ran the program in UGS. Only to have the parts cut 1/2" through the 3/4" stock. I measured the cuts with digital calipers and the final cuts are EXACTLY 1/2" which I find strange. Here is what I have done thus far:

Did you accidently set the stock thickness to 1/2" in fusion? Nope, went back and checked the model, confirmed it was .75" and even re-exported the the code. Ran that new code and had the same issue.

Is there an offset accidently inserted for the bottom height? Nope, the bottom heights are set to selected contours and the simulation even shows the cuts going full depth.

Did part of the programming get cut off? Nope, the completed cut has the tabs that I programed in so the machine is running the program to completion.

Is your Z axis correctly set in the WCS? Yes, used the touch plate to confirm the correct height for the Z axis and when the program ran it started cutting immediately. Meaning the missing 1/4" is not with the machine moving around the outline of the part before reaching the material.

Is your Z axis calibrated with the correct steps/mm? Yep, sure is. I double checked this.

Any other idea what may be going on? The only thing I can think of is maybe a loose set screw? Any help would be appreciated!

What does the Gcode say? Does the Gcode go all the way down to 0.75"?

Can you physically go down the 0.75" Is the router hitting the surface or something and causing missed steps?

I am not a GCode master, but I have attached the code if someone is able to take a look and double check me.

1001.nc (39.6 KB)

It appears like you’re zeroing off the wasteboard. The Gcode does cut down to zero so I’d think it’s something mechanical causing a physical blockage.

You are correct about the zero. I will double check to make sure there is no blockage when I get home from work. Thanks for the input!

I went back last night and checked that there wasn’t anything interfering with the movement of the z axis that would prevent it from reaching full depth. I also was able to jog the machine with no issues down to the full extension (well past work z0). I checked the tightness of the collett and verified that the bit couldn’t have slipped.

The only other thing I can think of is that the axis is slipping somehow, so I took the set screws out of the two z axis pulleys and added some fresh lock tight. I’m still using the stock set screws so maybe a look into swapping them out for a button head machine screw so I can use a larger allen wrench.

Outside of that I really cant think of anything. I have a wedding out of town this week end so next week I will run some more tests and see what I find. Thanks again for the help!