Good Morning from my Robotics Lab! This is Shadow_8472 and today I am learning a lot about the medium-grain details of printer calibration. Let’s get started!
Low Filament
My red filament is almost gone. I was considering using the rest on printer calibration tests, but when I found it broken, I went ahead and readied my white filament – the spool I have historically had a harder time with. I used my loop of cleaning filament to reach into the print head and push/pull out most of the remaining bits of red gunked up in there. I found a little red afterword, but there was surprisingly little leftover overall.
My printer’s print head works by grabbing the filament directly above the hot end, and there’s just enough room for filament to get lost during loading. I didn’t think much of it when a section of filament broke off in there. I made note, then set the printer up for several hours of operation. As of drafting this paragraph, it hasn’t caused any problems, but I’ve already researched the solution.
Temperature Tower and Mini Test
The first thing I printed was the temperature tower using the same .gcode I downloaded in a previous post. I should have the skills to slice up one for myself now thanks to playing around with the PrusaSlic3r interface, but I’ve used it before and it didn’t destroy my printer. I was expecting this filament to want it a bit warmer than 185 degrees C, but I was surprised when the only slightly warmer floor for 190 turned out the best.
I sliced up a 190 degree version of the mini all-in-one printer test. When I printed it over the central bed’s scratch, I saw a black spot in its middle of the first layer. As the build plate deformed, that must have been where the material went. Other results appeared to be on par with when I successfully printed one in red: I could read more of the test labels, but it felt brittle. The stringing test actually broke in an accident in the completed photo booth.
Benchy, the Benchmark Tugboat
I took part in a 3D maker tradition and printed Benchy, a tugboat designed with a number of challenging geometries. I’d say it came out pretty well – hardly perfect, but my untrained eye only noticed a couple major issues I took to the photo booth about. I found that I could actually use my begging-brother-special camera by letting it do whatever it wanted with auto-focus, then correcting it with a handheld magnifying glass.
I was able to post a series of pictures of Benchy in a few places on Discord and ask for help. Through feedback, I learned my most interesting issue is probably ringing. Ringing (as in like a bell) is when sudden movements cause vibrations the stupid 3D printing machine doesn’t account for. I need to print more slowly and work on a way to level my printer frame without resorting to paper soup like I am now.
My second Benchy went better overall. Per other advice, I used thinner layers and left my case open. I tried slowing the print job, but with Slic3r’s many settings and a delay in communication, I wrongly guessed that limiting long-distance speed would improve quality the most when I should have gone after perimeters instead.
The print itself has more, smaller flaws than my first. For starters, the lettering on the bottom totally failed. I got these odd bubbles over the ship deck and cabin roof. Other than that, the layers were all a whole lot smoother, there was no stringing, and a plaque on the back was clearly something –it wasn’t legible– but it didn’t look like a random mess. I also had some bubbling along the tops of the deck and the cab roof: probably steam from hydrated filament.
With my white filament sent off to the dehydrator, I printed a couple more Benchys in red. They both turned out about the same. The one where I added the front panel back in fixed one of two of the water lines, but seemingly made the other one worse.
Over on the dehydrator, my old, white filament is in for the thermal stress gauntlet. I ran it closer to the glass transition temperature than before to the point where a loop of filament sticking up collapsed under its own weight. Weighing it before and after showed no change in weight. It at least looks like I didn’t accidentally melt the whole spool. If I did, it’s tricky filament anyway. It still feels brittle, but I’ll try using it with a few larger prints as-is and see how they turn out.
Side Project
As soon as the calibration part was off the printbed, I started on a gift for my sister, Taz. She showed interest in helping with cleaning Twilight, so I made her a figure of Tails, Sonic’s two-tailed sidekick/best friend. I found an offering on Thingiverse with Sonic, Tails, and Knuckles. I didn’t like Knuckles’ pose, and I personally prefer Tails anyway. Later, I thought of about eight good reasons pointing out the back of Sonic’s head as to why he might be the more challenging cleanup (his quills).
I wanted Tails to have an inch of height for every foot the character is tall. Tails’ base plate was about 1/8 the height of his figure overall. I grabbed his height from the Sonic Wiki and scaled accordingly. There was no way I would be getting away without at least partially printing on the scratch, so I just left it centered.
While trying to remove unnecessary supports, it became apparent that these models can’t have been intended for anything but resin printing. Internal voids kept begging Slic3r for support material. I removed them in Blender so I could use my favorite infill setting (15% 3D honeycomb). I found another cavity for his mouth and tongue, but I felt lazy and fed him an appropriately squashed and rotated solid “sphere” object to fill his mouth instead. Thinking of infill, I knew the bottom of the baseplate would be due for some sort of modification, so I just printed it solid.
The figure came out… well, let’s just say it was a learning experience for both of us. I may have rushed the slicing a little to keep the secret. The supports were a mess. The print was plagued by this ringing phenomenon I had yet to learn about, and his arms, legs, bangs, and face/chest fluff were tiny – as well worded by Taz when she said something about literally knocking his socks off. He came out recognizable, but a larger follow up attempt is in order after I finish mastering the not-quite basics presented above. For what it’s worth, the base does have some decent heft to it.
Takeaway
I’ve already said this, but there is a lot more to 3D printing than sending it a file and hitting go. Then again, where was consumer 2D computer printing when the technology was ten years old? There’s a story in my family about someone rewriting a pen plotter driver to cross hatch using long lines instead of filling each x individually. Likewise, people are still innovating like crazy before the technology is locked down to the point where it’s baby-proofed so much a first grader can work it without prior 1st hand experience, supervision, or even so much as an explanation.
There is fun to be had while it lasts, but there is a learning curve to climb beforehand. Proper diagnostics are key, otherwise I’m blaming everything on old filament.
Final Question
What is the most challenging tool you ever taught yourself to calibrate?