Sometimes things go wrong

If you frequent YouTube 3D makers or forums where people show off amazing prints it can be frustrating sometimes to have a string of failures while others are creating great things. What you should remember, especially if you are new to 3D printing, prints do not work like other consumer products. A great deal of tweaking takes place to get successful prints.

Barring some catastrophic printer problems you should not give up because each failure is an oppertunity to learn more and improve your printing skills. There is almost always a reasonable and fixable solution to any problem you encounter printing.

As an example, I recent designed a model for a power supply that not only took several iterations to perfect, but when it came to printing the final design I had repeated print failures. These were 5hr plus prints so often it was 3-5 hours of wasted print time and materials.

My first test print was in PLA to check dimensions. PLA is easy to print and the test came out decent. I printed this fast just to line up the print to the real power supply.

PLA print test version
PLA test print

For a power supply cover, however, I wanted to use PETG/PET so I made changes to my model and printed the next one in PET. This resulted in bed warping and a significant crack in an important part of the model. During this print the filament runout sensor triggered despite having filament pausing the print which may have lead to the layer separation. That is three major issues on one print.

PETG print with crack
Cracked PETG print

Third print. This one warped badly on both sides so I stopped the print early because it was well on its way to failure.

Badly warped edges forced me to cancel the print

Fourth print. Everything went great until 3/4ths up a nozzle jam resulted in significant under extrusion.

Clogged nozzle results
This is what a clogged nozzle print  looks like

Quick aside: The nozzle not only jammed but cold pulling filament did not fix the issue. The jam was at the tip of the nozzle and no amount of cold pulls were getting the filament to flow better until I used a acupuncture pin to push up into the headed nozzle. Subsequent cold pulls pulled out the debris and the jam was cleared.

The final print, while not perfect (as you can see from two of the layers), did not warp, did not crack, and there were no significant nozzle issues.

Final print
Final usable print

Some of the things learned from these prints:

  • It takes time to find the right settings for new print material. I have printed with PET/G before, but this was a new brand and it turns out it needed more heat from the heated bed than the manufacturer recommended and more fine tuning of the first layer.
  • If something goes wrong try and figure out what the issue is before attempting a new print. I’ll be the first to admit that sometimes prints fail for no good reason, but it is rare. Usually there is a reason and you’ll save frustration, time, and materials if you can narrow down the cause from one print to the next.
  • PLA is easy to print with, but other materials can be harder and take more tweaking. Before you print with materials other than PLA, make sure you have your printer making great PLA prints first.