Why does it not cut all the way through?

Hello everyone, I’m sorry this is my first post though I’ve been lurking for years. I have no idea what words to search for this problem so I apologize if it’s an easily solved issue

I’ve used my gf pro very sparingly since the original KS, but I have been using it more regularly recently and run into this almost every time

Why does it often not cut all the way through the pg materials with the cut settings on the app for the pg material (in this case medium maple ply)? Am I doing something wrong or is there an issue I need to fix?

I’m sorry for the vague question, I’m not sure if it’s a problem with the app settings, the physical gf or camera, my files, or my process? I’ve tried manually focusing etc but it doesn’t ever solve the problem. Originally I thought it was because the material was warped but it has been happening recently even when it’s brand new pg sheets stored flat.

Thank you ahead of time

1 Like

Brand new pg sheets can be warped. Even a little variance can cause the laser to be out of focus and therefore not cut through. Other common reasons for cuts not going through include dirty optics. Have you cleaned all of the optics - lens, mirror, the window on the side of the printhead, the window on the side of the machine, the camera and the two little windows underneath the printhead. It looks like the cuts get weaker the further to the right of the bed the are, which implicates the side window - number 8 in Things That Need Wiping

3 Likes

Many times this ‘can’ be a result of the optics needing to be cleaned.

3 Likes

Thanks! I do recall cleaning the lens before but I don’t think I did it completely, now that I’m watching this video so I’m gonna try doing this, thank you!

2 Likes

Of course, make sure everything is clean and flat to start with. But if that doesn’t help, given the age of your machine, your tube may be reaching end of life. It’s rated for 2 years. It doesn’t matter how little you used it, CO2 gas escapes from the tube over time, starting from the date of manufacture. If even after cleaning you consistently can’t cut PG material at PG settings, the support folks can slow down your machine to buy you some more time. Eventually, the tube is a consumable and will need replacing.

2 Likes

Not wanting folks to panic at the 2 year mark. Have had mine for 4 years now. Granted I’m not a heavy user but have noticed zero change in the laser power. Settings designed to just barely cut through are still cutting completely through. From time to time I might have an issue but so far it has always traced back to clean windows & mirror, very slightly warped material, incorrect height settings, etc. In other words it was always me not it.

7 Likes

Seconded. Sometimes it’s difficult to tell if a sheet is perfectly flat visually. My habit is to gently tap a sheet of wood with my finger all over and listen for any warping. If I hear any I may use a different sheet while I let that one re-flatten (temp and humidity can cause temporary warping and can also return it to flat), or I may cut a sheet so that what I’m left with is flat (depends how much of the sheet I need to use at that moment), or I may use magnets in the high spots to flatten it down (again, depends how much of the sheet I need to use at the moment).

Also seconded. I have no expectation that this tube will last a lifetime. But, like @rpegg, I’ve had my ‘forge for >4 years now and if there’s any difference I’m not seein’ it.

4 Likes

Hello, @astrolaboz I’m sorry to hear about the trouble with cut through you are experiencing, I will do my best to get this issue resolved for you. I think I was able to find the print you referenced:



Is the photo you shared the back side of this print? Let me know. If this is the case then it should of definitely cut through based on the settings that I saw from that print.

Also, It sounds like some of our helpful patrons in this thread already recommended to clean your optics.

Could you provide photos of those optics when you have a moment?

  • Both windows

    • The printer head window, on the left hand side of the printer head

    • The laser window on the inside left of the Glowforge

  • The printer head lens

    • Both sides of the lens, top and bottom

  • The mirror inside the printer head

  • The bottom of the printer head with the lens installed


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


1 Like

Hello! Thank you for the response, it was the backside of that print. I have yet to reattempt the same print since, but I did go ahead and clean the optics fully and tried the Gift of Good Measure; it was the same problem but after trying out @Tom_A’s suggestions I realized it really was warped sheets! A second cut with a shorter, flattened piece cut Good Measure with no issues, so now I feel quite silly, but I really want to thank everyone for the thorough help! I had believed the sheets to be completely flat because they are stored flat but perhaps temp/humidity affected them. By eye, they seemed completely flat to me but I know better now.

I do have a question though: I assume since others do this it’s safe, but I did feel a little nervous using the magnets to hold the slightly warped sheet down. Is this really okay or are there precautions I should take? I know there are magnets in the laser head so I was concerned, but maybe I’m paranoid. It turned out a perfect cut but I just want to make sure haha.

2 Likes

I am glad you are printing again. Magnets are successfully used by some, but strong magnets have also caused air assist fan errors. An alternative to magnets is honeycomb hold down pins. Here is a link to the file. Honeycomb bed holdown pins

2 Likes

Fantastic! I’ll get to work on those! Thank you for the link

Hi @astrolaboz. Thank you for your follow up response to update us regarding the warped material being discovered as the cause of the cut trouble. @dklgood gave a great suggestion of hold down pins versus magnets to help secure material. Because you’ve gotten some great advice to help you resolve this, I’m going to move this thread to the Everything Else section. This will allow you to continue any discussions including any tips and tricks for prints. Thank you!

All I can tell you for sure is I’ve used these for years and haven’t had a single issue using them. Sometimes I’ve even doubled up on them. Again, no issues. I’ve used several in various places on a sheet. No issues. Do ensure your cut will not cross paths with a magnet, however. I imagine reflecting the beam back into itself could certainly cause damage or fire. But otherwise I suggest you’re fine using them. I use them so often I don’t even think about it. The box of magnets sits on the shelf next to my 'forge. :slight_smile:

1 Like

This isn’t really a wise MO in general :wink:

As long as the magnets don’t get near the laser head it’s fine. If the laser head passes near strong, unshielded magnets while it’s cutting that can cause one of the fans in the head to stop spinning which throws an error.

1 Like

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.