Glowforge seems to be losing power

The last couple of prints I have done I had to reduce the speed of the glowforge to about half or maybe even less. We first noticed the seemingly reduced power before Christmas last year but were doing mostly engraving and that seemed to be ok with the materials my wife was using. We always had to reduce the speed by 10 or 20% on proofgrade materials but now I have to reduce it about 60%. Is there an easy way to tell if the LASER is losing power? I guess I could run a Gift of Good Measure test but I feel confident that it won’t cut through.



Have you already done all of the cleaning steps for all of the lenses? This is critical–and often needed well before 40 hr use pending materials you are using. This is the #1 reason I’ve found if I seem to be “losing” power–time to clean!

And also clean the bed & exhaust fan & duct work–if the exhaust is getting restricted, that can affect the quality too (dust blowing around a laser beam scatters the beam a bit & effectively reduces power at the focal point).

Also be sure all your material is really really flat and tight against the crumb tray. I’ve had some sheets of PG that are so warped, I can’t really use. Pin the material down so you don’t hear any hollow sound or pings. Any gap will affect the cuts, but less an issue with etching.

Hope that helps, or some others may have some other ideas…


Did you check the Support page: ?

If you’ve had it that long and you haven’t ever cleaned it, that is almost certainly the cause of your problem. As I’m sure you know, lasers use light, and that light uses optics, mirrors and lenses to get from the laser to your workpiece. Lasers also make a lot of smoke and dust, which accumulates on the optics (which are exposed to the environment inside the enclosure). That accumulation reduces the amount of laser energy that makes it to whatever your lazing. You need to up the power or reduce the speed to compensate. If you don’t do the periodic maintenance, eventually stuff will be too dirty to get any useable power to the workpiece.

Also, the exhaust fan and air-assist fans can load up with debris and they also need periodic cleaning.


Thanks for the response. Yes, I actually am at the point of cleaning the Glowforge before every print. Our unit actually has very low hours on it too. I’m aware of the importance of flat materials and I use T-pins to hold the materials to the bed.

Yes. I have checked this page and followed all the steps many times.

Thanks for the advice.

I’m very familiar with cleaning the Glowforge and because of the loss of power I clean it every time I use it so that dirty optics wont contribute.

I have not cleaned the exhaust fan but I will do that. There does not seem to be any issue with exhaust as I can see the fumes sucked out very rapidly. But to be sure I’ll clean the exhaust.

Okay forgive me for asking but it does need to be clarified since some of these are very easy to overlook and some folks have not seen the new guidelines that Glowforge has added recently…

Have you cleaned the…

  • Lid Camera?
  • The lens inside the head? (It requires removal with the blue magnetic tool, and needs to be reinserted in the correct orientation.)
  • The two small round windows underneath the head?
  • The round window on the left side of the head?
  • The round window hidden underneath the left side of the machine, opposite the laser arm?
  • The mirror?

There are pictures of what to wipe here in the Support section:

They shouldn’t require cleaning before every print. But missing one can cause what you’re describing. So checking to make sure that you caught them all is worth the time.

While you are checking, if you see any scratches or damage, take a picture and let support know, or post them here.

They will need to see them so they can tell you what comes next. :slightly_smiling_face:

Ya know? It’s been a couple of years now and I still forget to clean those most of the time.

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Me 2! :smile:

Oh, another thing to check is the airflow into the unit on the right side–make sure there’s nothing blocking that or a piece of paper stuck up on the underside–something else I’ve learned to check for frequently!

As others noted, you shouldn’t need to clean before every use, but when you do clean, make sure you get everything…

Also consider the ambient light–e.g. close to a window that gets lots of sunlight? Though most often that affects trying to center/focus, bright light may affect more–e.g. summer worse than winter months? I recall I had a “loss” of power after a while–I started using my unit in Nov 17, have it next to a south facing window–and seems it was spring when did notice “loss of power”–but now in the habit of closing the curtain if it’s not fully overcast day, and the laser power has been consistent… May be pure coincidence, but it eliminated a variable from the environment!

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Hi @sarjanlong, I am so sorry you are having issues cutting through Proofgrade Material! Thank you for taking the time to do some initial troubleshooting. Can I have you check a few more things as well?

Please send photos of all your cleaned optical components, with special attention to any damage you might find:

Once we have those pictures, we’ll follow up with next steps.



Hi Jules,

Thanks for checking on the details. Yes. I have cleaned all of those. This machine has never cut all the way through proofgrade. But the advice I always got was to reduce the speed by 10%. That was enough until recently. The last cuts I did were ridiculous. Even 2 passes at reduced speed didn’t make it through.

I see a message from support so I will follow their guidance now and see where that goes.

The Glowforge is near a small window, however the latest cuts I worked on were in the evening so no extraneous light. I’ll check the airflow this evening when I’m home.



Thanks for the reply. I’ll clean everything and post pictures of all the optics.

@sarjanlong, make sure that your materials are flat, flat, flat. Use magnets or pins to make sure that Proofgrade is not buckled. Even a small warp will mess up a cut.

You probably know that… but it can’t hurt to mention it.

If your machine has never been able to cut through nice, flat Proofgrade on the stock settings, you may have a warranty issue.

Fingers crossed for you.

Is the lens inserted correctly? If it was doing okay until a recent cleaning the lens might have been inserted upside down. That will keep it from cutting through, and it happens a lot more than you’d think.

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Here are the pictures.

I did a cleaning of all the optics and then pulled the tray out and cleaned the bed and dimples. Then checked the exhaust fan which really didn’t have a lot of gunk in it. No obstructions to the air intake.

Then I put in a sheet of Medium Draftboard (full sheet held down with T-Pins) and ran the Gift of Good Measure print with everything set to default. The print did not come close to cutting through. Not even a hint of it. Time of print about 7pm EST on 9/5/2019.

What else do I need to provide? I also have a video of the cut in progress and the finished product. I can upload those to dropbox if you would like them.

I always use the T pins to hold materials flat.

The lens is inserted according to the instructions on the troubleshooting page.