I did a Stress, Bridge, and Overhang Test with my 3D Printer. It is important to get a good idea how well your printer prints so you can save filament. You save filament by knowing how much support you require and how well your printer handles your sliced 3d models.
I first did a stress test by 3d printing several bulbasaurs: (Link to model) at .07 mm layer height and at a print speed of 50 mm/s. Each Bulbasaur took 7 hours to print and immediately after one is finished I started the next one. I printed a total of 4 and the Bulbasaur in the photos is the last one that came off the print bed.
The print came out fine. Albeit there are some issues with layer quality. There is little to no banding but we could see some minor oozing which is fixable by adjusting other printer variables. But I would like to say the Robo R2(my printer) meets expectations, not once did I have to check on the prints and it felt reliable enough to print longer prints. I did not notice any burnt or oozing filament, no browning out, inconsistent hotend temperatures, no hiccups at all.
I do want to note that I disabled the filament sensor before doing this test because it has been known to give false readings.
After (7×4=28) hours of non-stop 3d printing, the Robo R2 gets a thumbs up for reliability. Just look how smooth Bulbasaur’s chin is:
The next test I did was the overhang test using this thingiverse model. There is not a lot of say about overhang but it gives you an idea how steep your 3d printer can handle. With PLA, my RoboR2 was able to print up to 30 degrees without problems. Beyond that and you will start seeing drooping and poorer quality pillars.
Finally, I did a bridge test with this thingiverse model. Bridging is dependent on print speed and I was only at 50 mm/s. I am sure if I bumped it up to 75 mm/s the bridges could be created much longer.
at 50 mm/s, sagging is noticeable after 20 mm. beyond that, you will see drastic sagging.
to my surprise, the top layer at 100 mm is created nicely. So if you were to print something and the inside quality is not of concern, you can print an object at 100 mm. With my current settings.
Here is a picture of the sagging at 100 mm. not bad.
Alright the Robo R2 with PLA and print speed of 50 mm/s can print well with 30 degrees overhang and bridges well up to 20 mm. The results would be different with other materials or with different print settings. This gives me an idea how to set the support settings for my prints.
I am sure you will benefit from testing your printer too. It helps save filament while maintaining quality and makes you a more efficient 3d printer-rator.