Large print keeps warping at corners. Tried liquid glue and brims

Hello everyone. I am at a loss. I am trying to print a piece of an Axe and it keeps warping at the corners. I need the bottom to be straight so when I glue the pieces together there will be no gaps.

First off I cleaned the bed with warm water dish soap thinking it could have been my hands. Second I measured the bed with a metal ruler and did not see any gaps. I bought liquid 3d print glue and it seems to not make a difference. Previously, all my prints did not use any glue and it turned out perfect.

I am printing Sunlu PLA+ Nozzle at 220C for the first print. The Bambu Gold Pei Textured bed with temperature at 55C. I used a 10mm brim and used liquid 3d print glue. The P1S door is slightly open and with the top on. Fans are run at default.

For the second print I am printing Sunlu PLA+ Nozzle at 215C for the first print. The Bambu Gold Pei Textured bed with temperature at 60C. I used a 10mm brim. This time I added helper discs to the corners as I read that it would help with the warping, but the same issue persists. Aux Fan is 50% Parts fan is 50% No cooling for the first 5 layers and still the same issue. The top is open and the door is open.

Any ideas? Do I need to turn off all the fans? Do I need to buy a different bed? Let me know if you need additional information.





I’m going out on a limb here and am going to say that cooler air coming in from the slightly open door might be causing it to warp. Does it warp soon enough that you can cancel the print before wasting filament? Try rotating the print 90° on the bed so that the point is closer to the hinge. Also, if you have the aux fan on the left hand side of the enclosure, turn it off as it may cause it to warp with it turned the other way.

You could try a raft but I don’t know how cleanly it will come off and it may cause issues at the joint.

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The brim looks good. I would try to disable the fans and keep the door closed.
Because temperature differences causes these issues…
If that doesn’t help, you could try different bed temps. Maybe 50? Maybe 70?

First off, Sunlu’s PLA+ is the worst for warping. I ended up using the Cool Plate with a heavy coat of glue stick. Though my prints were rectangular and didn’t come to a sharp point. For what it’s worth, I won’t be buying Sunlu’s PLA+, their normal PLA seems to work pretty good. My best suggestion is to try another filament. If someone proves me wrong I’m all ears though.

I’ve had success with large eSun PLA+ prints. But it took quite a few tweaks. Here’s a list of additional things to try (no reason not to do them all):

Print settings

  1. Print bed temp at 65ºC
  2. Print temp at 225º for the first layer, then decrease to 220º
  3. Disable both the AUX fan and the chamber fan
  4. Keep the top and the door closed. You want the chamber to be warm.
  5. Print a 2-layer brim (try this last)
  6. Wet sand the PEI plate with 1000 grit wet-or-dry paper, flush thoroughly, then clean with 99% IPA and a microfiber cloth. (Buildup on a PEI plate requires something abrasive to remove it - it will not wash away or dissolve with solvents.)
  7. The cold plate with PVA glue (in this case, better than the liquid BBL glue in the green tube) is perhaps a better alternative than the PEI plate in this case. Note: I had such good adhesion on one big print that it pulled the plate away from the bed!

Model Changes

  1. Reduce the number of solid top & bottom layers
  2. Reduce the infill percentage (both of these increase internal stress - PLA will always shrink when it cools). Use the smallest % you can without affecting the surface area.
  3. Change the infill pattern to one that creates less stress in the warping plane. Support cubic might work well, as this is pretty sparse at the bottom and only starts to get denser when getting close to the surface.
  4. Since your model will be glued together on the bottom, you can reduce stress on this layer by creating pockets on the base that will decrease the surface area.

Hope this helps!

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Thank you for the reply lasermike. I forgot to mention that I tried it with the door closed and top closed and got the same result. The warp happens like 2/5 of the print. I’ll try turning off the Aux fan first and try again. Then probably see if I can rotate it so it is closer to the the hinge.

I will look into the Raft.

Thank you ouweRammer. Let me disable all the fans and try it with the door closed. That is a definitely a start to try different temp beds such as 50 and 70.

Thank you for the reply LarryCnAZ sad to hear that Sunly PLA+ is worst for warping. I didn’t have any issues with it before and I am stuck with it for now. Maybe it is just because I didn’t print large prints and smaller things.

Thank you for the detailed reply Rom3oDelta7! I will give your advice for the print settings and model changes shot and see how it goes! I was using the default grid pattern with a 7% infill. Will change it to cubic and a 5% infill. Going to try with the Aux fan turned off and the print temp bed at 65C and 225 for the first layer and decrease to 220.

Make sure you use “Support Cubic” here and not “Cubic”. Support cubic will infill sparsely on the bottom and get denser towards the top of the object you are printing. This is what you want in this case to minimize warping.

I tried both cubic and support cubic and the infills ended up breaking apart on its own so I just went with the default grid and had no issues. Sucks, because from your logic yes it would prevent warping.

An update. I gave up on having the bottom flat and not warped since I printed it so many times and didn’t want to waste any more filament. I ended up trying to sand the bottom down to get it somewhat flat. If I need a large print printed again then I will try a couple of more things. I’ll share my findings so if anyone is reading this can maybe try and improve

Turned off all cooling from the Aux Fan, Chamber Fan, and Parts fan. It made the bottom flat, but it made the 3d printed part ugly.

Credits to Rom30Delta7 settings

  1. Print bed temp at 65ºC
  2. Print temp at 225º for the first layer, then decrease to 220º
  3. Keep the top and the door closed. You want the chamber to be warm.
    Other implementation
  4. 10mm brim
  5. Used 5% infill with the default grid pattern.
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I had issues with my first p1p using the Aux cooling fan and pla warping. so i dont use it at all anymoreon any of our p1p’s. But heres something ironic our P1S’s all run with factory settings and fan speeds.

What you have going on seems like a cooling issue. I know on our P1S machines we remove the top lid and close the doors, mostly so we dont break one, and have had no issues. Good luck on finding your culprit, its frustrating when things dont go as expected.

Thank you for these settings! I had such bad experience with Sunlu PLA+ in the past.

Never had the auxiliary fan and never had any issues with any eSun PLA+. I would say it’s the most reliable filament I’ve used out of many.
Don’t use the aux fan. Use the print and filament profiles from the eSun website.

Relative newbie here. I appreciate all the tips and suggestions. I had a similar problem with BL PLA. Previously, I printed with the door open and a 5mm brim. I tried printing with the door closed and a 10mm brim. That solved the problem. Hope this helps.

Multiple people have received sunlu pla from bambu labs where the packaging in the box was sunlu. It’s not a sunlu issue.

What version of Bambu Studio are you using. Try rolling back to an earlier version. I had similar issues after the most recent update and after reading other people had the same issue (after the update) I went back to an earlier version and instantly fixed my problem. Maybe a coincidence of sorts but that is just my experience. Worth a try maybe.