Stuck on centering/scanning

Checking in with what seems to be a common problem these days: stuck on centering at startup. Sometimes the web app says “scanning”, sometimes “centering”, in neither case does the Glowforge seem to be doing anything. The wifi is fine (and I reset it just in case), I’ve cleaned all the things, am now leaving the lid open for a while as per the advice here…

Update: left the lid open for 15 minutes, with the head manually centered, and when I closed it, it started moving things around and went back to normal. Hooray!


Just to be clear, you can damage the machine if you move the gantry or head when the machine is on.

I got in the habit of manually centering the head years ago when we were having difficulty with the startup calibration.

I’m so sorry you hit a snag.

The issues you’re seeing might be caused by a poor connection with the cables on your lid. Please follow the steps below to check the lid connections:

  1. Turn off your unit.

  2. Open the lid.

  3. Using both hands, gently roll the laser arm to the front of the unit.

  4. There are 5 clips pictured below. Check each one to ensure it is closed. The clip should lie flat, and you shouldn’t be able to flip it in any direction.

  1. If any of the clips are open, ensure the cable is inserted straight into the clip and close the clip.

  2. If any of the cables are misaligned in the clip, take a photo of the clip and cable and send it to me so I can take a look before you proceed. Do not try to adjust or reseat the cable.

  3. Close the lid.

  4. Turn your unit back on and wait for it to calibrate.

Let me know how it goes!

i am also having this same issue, i have double checked all the ribbon cables and it still stays stuck on scanning. If i reboot the router and glowforge it will come back up stuck on centering. after several reboots it will again work for 2 or 3 cuts than gets hung up on scanning again. this has been really problematic for the past week.

The problem has come back twice now today. The first time I was able to get things going again by turning the machine off and manually centering. This second time I am so far unable to get it going again.

The cable clips are all fine. The wave of people all having this same problem in the last week seems to me to strongly implicate a regression from a software or firmware update. I would really love to hear someone from Glowforge either acknowledge this possibility or somehow dispel it. I’m happy to work with someone to debug since, sadly, I seem to be able to reproduce the issue.

FWIW, in terms of both timing and type of update, Improved Accelerometers: 5/20/2019 Latest Improvements seems very likely connected to these issues.

A couple of more pieces of info that may be of interest either to the support team or to the various others with similar problems right now:

  • turning it on with the lid open and leaving it that way for 10 minutes or so, then closing it, does seem to fairly reliably let me get a cut or two in before the problem comes back.
  • on some but not all cuts the app seems to lose track of the machine towards the end; the cut will finish while the countdown timer is still ticking, and when the timer does get to zero it shows the message about cooling, indefinitely, even after the lid has been opened and closed.

I’m sorry for the delay in following up on this thread. We’ve been able to definitively identify this as a hardware problem and the replacement part that we’re sending should resolve the issue for you. If you have any further trouble once you’ve received the part, please don’t hesitate to open a new thread or email us at

1 Like