I’ve had some pretty bad alignment problems before, but this takes the cake. I’m even using proofgrade maple. How does this even happen?
Edit: the 2nd attempt printed fine, but this has happened multiple times in the past and I’m tired of wasting material.
Something went wrong for sure. Note that the Snapmark has drifted over so there is something goofy. I don’t recall ever having a print this far off the mark. And if it happens often, then something could be off with your machine.
This isn’t the first time something similar has happened to me. I had also already cleaned all the lenses just before this print. The 2nd print was close in alignment, but there were several areas that didn’t cut through completely.
Is there any possibility at all that you bumped the head, or that the head was moved while the power was on?
It’s pretty apparent that for some reason the head was not where it thought it was.
That definitely looks like your gantry or belts hit something. Presuming you were watching, did you hear anything?
I don’t know how the head could have been bumped with the lid closed and only having a single piece of pg maple plywood in there. I didn’t hear anything weird, although it’s hard to hear anything over the volume of the fan.
People seem to find a way to do it every now and then. 
Did you power the machine off between the first attempt shown here and the second attempt you said was ok?
Yeah, I rebooted everything between attempts.
When using Snapmarks, I have occasionally had the wrong marks found that led to location being wildly off. It thinks the right one is really the left or something. One thing you can try is slightly tilt your jig or whatever the marks are printed on, and see if the Snapmarks are found properly.
I would inspect the belts/rails for debris. This certainly COULD be a software problem but start with the easy stuff that you can control.
The thing with this print is that I wasn’t using snapmarks. I was making a ruler with snapmarks.
Thanks for letting us know about this, @kevquang. Often, when we see an offset this large, it occurs because the head was physically moved or accidentally bumped, which affects the current calibration. I extracted the logs from the print in question to investigate, and it looks like the printer head did not start from the “home” position. At times the head can be moved or bumped while preparing a print, and this can be fixed by rebooting the Glowforge to recalibrate. I’m so sorry for the inconvenience.
If you run into any other trouble, please start a new thread, or email us at support@glowforge.com. Happy printing!
