Trouble printing temp tower

Snapmaker 2.0
1

Hi all -

I’ve been printing with my SM2 A350 for a while now, with lots of good results.

I switched to the SM White PLA filament, and am trying to calibrate for the filament.

I’m trying to print a temp tower that I got gcode for from https://teachingtechyt.github.io/calibration.html#temp
(gcode attached).temp01-40mms-1mm-190-210.gcode (568.7 KB)

It keeps failing - as it gets higher, it peels up from the print bed on one side, until it finally works itself free. Here’s the most recent print as an example:
Google Photos

This is my 6th or 7th try. What I’ve done so far:

  • Calibrated my k-steps (currently E234.21)
  • Re-calibrated bed.
  • Twice.
  • Added glue stick
  • Added painter’s tape
  • increased first layer print temp to 75
  • On this last one, I even put painter’s tape ALONG THE FIRST LAYER of the print, to try and absolutely secure it - which I thought was cheating, and it STILL failed.

My theory is that since it’s printing in a garage, where the ambient temp is pretty chilly (56 F / 12 C) Maybe the bottom layers are cooling too fast? I’ve been printing in the garage for a while, and do see warping (corners pulling up), so am working on an enclosure to help keep it warmer.

I also think, compounding that, the gcode that this site generates has a skirt but not a raft, and no options for changing adhesion settings.

But I don’t think that should matter - the SM printer should be able to print this and have good enough adhesion with a skirt, I think.

I’m going to focus on ambient temperature (add enclosure, maybe even a small tabletop space heater to keep the air volume warm).

Is there anything else I should try?

Thanks!

2

Are you talking about the heated bed and not the hot end? If so, for PLA you should be using 50°C, ignore what Snapmaker says. Also, when printing in an environment that is below ~65°F, you will run into different issues. With resin printing you can’t print if the temperature drops below 68°F. FDM printing is more lenient when using some materials, but at 56°F you will run into overcooling issues, and poor layer adhesion with all types of filament.

Your picture shows that the bed was way to hot, which caused the base of the print to deform. The cold ambient temperature caused the bridges to string, and to not adhere to one another. If you turn down the part cooling fan, or even completely off, you might get better layer adhesion, but you are better off heating the printing area. Don’t let the ambient temperature drop below 68°F.

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3

Awesome - thank you. I did just try putting a loose enclosure around the printer to try and trap some heat. Will lower the bed temp as well, and try turning off the fan as well.

Do I need to reduce nozzle temp with the fan off, or make other changes?

Thanks!

4

If you are able to increase the temperature to 68°F or higher (preferably 72°F+), you can use the part cooling fan as you normally would (usually 100%). This should work for PLA & PETG, and probably TPU as well. However, any filament that is notorious for warping, or splitting, requires a much higher ambient temperature. Like ABS & ASA work best when the ambient temperature is 40°C or higher, and no part cooling.

If you can’t get the temperature in the enclosure high enough, you’ll need to do a lot of experimentation to figure out what speed to set the fan to for each spool of filament. It will vary based on the brand, the ambient temperature, and even the color of the filament, which is why this should be an absolute last resort.

BTW, if you leave the printer to sit in the enclosure with the heated bed at temp for about 30 minutes, it will most likely be more than enough to raise the ambient temperature to a good level. :wink:

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