PETG Melting as it prints?

Bambu Lab P Series Troubleshooting
1

I’m printing a part that has a flat scoop like part that seems to be suffering from the heat, as it prints. IT is printing flat on the build plate, but then as it starts to slope up, it appears that the heat from the plate is causing it to deform a little?

Any thoughts as to how I can stop this from happening?

IMG_9134
IMG_91341920×2031 307 KB

2

It does not look like a print bed temperature issue. Those types of overhangs are more difficult to print with PETG. Some things you can try:

  • Slow down your outer walls
  • Lower the print temperature by 5 deg increments
  • Enable/paint supports in the problem area
1 Like
3

I think @blchandl2 is on it about the overhangs. It looks like you may need a different print orientation or supports to get a better print.

4

Thanks gents, I’m printing now with a support that goes to the top of the problem area. Will report back.

5

One thing I forgot to mention was enabling variable layer height with smoothing. It can use thinner layers in the problem area and thicker layers in the other areas to keep the print time down.

1 Like
6

So I have tried near every setting one can imagine. I’ve added Support up past the problem area. Turns out that along with the Top Z Distance in Support made the most difference. From 0.275 > 0.2mm and from 1>2 top interface layers.

I am still however not happy with the result. It is not a structural issue, but a cosmetic one.

I slowed outer walls to 150mm/s , lowered print temps a couple times … Ironing did really nothing. I just cannot crack this nut

IMG_9141
IMG_91411920×1940 424 KB

7

Could you lay it on a side? It is hard to tell what this looks like from the pictures.

8

Unfortunately I cannot change the orientation as it has a lot of other protruding parts on it. I angled it 15• but that didn’t help.

Starting to think PETG just can’t handle it.

I have some PAHT-CF landing tomorrow so after a dry, I’ll try that

9

variables are too much, if you upload your settings it’s possible to check it faster.
My new sub hobby with bb 3d printer is to try to use lesser custom settings but obtaining good results. I am printing a pokedeckbox without supporting the overhangs on the bottom of the main body, and it works without hanging filaments, for now. (i still need to increase walls because with 3 you can see the infill -petg matte red- probably i am gonna 100% infill next time)