I ran into an issue where I was pretty sure about my placement of a simple rectangular cutout but after the piece was finished I found it to be an inch taller than what I put in CC.
I just attempted again on a scrap piece and it is still off by even more this time??
I’m zeroing the tool at the center of the piece and am getting these results. normally I use the probe on the corner but for this project the material is too large to use the probe for the corner.
again, i’m zeroing the router at the center of the workpiece and starting the toolpath at center. but for some reason I can’t get my bottom cut where i want it to be at 3.25" from the bottom of the workpice.
It’s cutting the overall shape just fine, the only problem is that it’s not positioned where it needs to be on the material. I’m using the probe for the z-axis so it’s cutting depth ok as well.
one thing that at some point I had, is that I hit the back of the machine halfway my cut… which causes it to miss steps, and from there on, all measurements are off.
Is this a front-to-back misalignment or a left-to-right? (from how it was in the machine)
the way to try this, is to turn off the power to the machine, and by hand, move the X beam (gantry) all the way to the back. That is obviously as far back as it will go.
If the hole you’re trying to make is behind that (or any other part of the cut) bad things happen.
Specifically, the machine THINKS it’s moving further back, say 1", but physically it is not (the stepper motors end up dropping some steps)… which is not nice. but worse, once it later moves forward that 1" again, it actually moves that 1" forward. So now there is a 1" difference between where you zeroed and where the machine actually is… and all cuts now are off by 1"
Now, the shapeoko might not be able to cut all the way to the very back as you might think if you look at the wasteboard… but it can cut forward a lot more than you think as well… so you can overhang on the front side…
(think of it this way… the router is to the front of that beam)
first of all, if you look at the preview you’ll see it’s not actually going to follow the line, it will just go to the beginning of the line, plunge…and stop. I found out this is because you left the contour toolpath “offset direction” to “inside/left”, while if you want to cut along single line you must use “no offset”.
Other than that, the line in that file is indeed at 3.25" from the bottom of the stock. Can you fix that offset, regenerate your practiceline code, and run it, to figure out if you still see the problem?
silly question but, did you check whether your stock was actually 18.03" along Y ? (the value you entered in the job setup)
My practice board was the same width but not the same y… it was a few inches taller which explains why it has been coming up higher Everytime I practice on a new piece that’s slightly taller than the finish product.
I moved my center off of 18" and voila it’s right where it needs to be.