Good Morning from my Robotics Lab! This is Shadow_8472 and today, I am on my 3D printer again for round 2 of printing a model of Twilight Sparkle. Let’s get started!
Preparation
I began with a fresh download into a clean project directory I designated. The “fixed” version from last time simply fused all the little details I wanted to delete/paint on later into one single model. I instead continued work with the unfixed version [1].
Like before, I used Blender to digitally clear out Twilight’s eyelashes and stitch her mouth shut. I really wanted to try printing her mane pieces separately so I could glue them on later, but I can’t Blender well enough to make that happen.
Over in Slic3r, I scaled the model up by half an inch from front to back. This made her feel a lot bigger, but not so big I was in too much danger of running out.
I played with paint on support blockers a bunch, but I found they weren’t as versatile as I would have liked. I found myself working more with the more geometrically themed blocks. Of note, I added one to the tight space between her mane and neck and a cylindrical one between her mane and forehead. As I finalized each block, I made sure to inspect the individual overhang layers to make sure they would bridge properly.
With the bigger model, I had to override the program into using solid infill for those fragile legs. The selection box was the same as the support blocker. I also told it to make Twilight’s unicorn horn solid at the base, even though it would have been fine with her mane intersecting it (another reason not to print head pieces separately).
As one final touch, I moved Twilight off to the side and removed her raft so the scratch in the build plate would only affect the support material.
Printing and Cleanup
Printing went smoothly. I checked in once an hour until she was done. The PVC pipe I’m using to extend the filament rack fell out again, but fortunately it didn’t cause any issues as I observed during a calibration print. This print used most of the rest of my spool of red PLA filament; it’s just starting on the second to last layer. I have a smaller print or two left, but that’s it.
Removal of the support material took about as long as last time – a full day plus a bit. This time, I tried to be more careful about her mane, and it paid off. Twilight did not suffer any ill effects for missing a few supports here and there. I even caught myself laying fingers on fragile bits while trying to get leverage on stuck bits elsewhere before I broke anything.
Despite the model being scaled up a little, cleanup wasn’t much easier overall. The cutters/needle nose pliers couldn’t reach as far between her legs, but I can get both those parts with sandpaper. The mane was as obtuse with me as before, but after a while, I managed to use a repurposed sewing needle and a bit of tie wire to leverage a corner to where I could get in there with the pliers. It felt so good getting that bit out, but I cracked the lock of her mane hanging off to the right. I want to print up some test pieces and practice repair techniques before continuing work on the real one.
Notes for Future Prints
If I make another attempt after this one, I may follow the fixed version’s cue and fuse all disjoint model pieces before exporting from Blender to Slic3r (over a .stl file). My hope is that Slic3r won’t get as confused with intersecting geometries as found in her mane.
In all reality, I should be thankful these prints are cleaning up as well as they are. The proper tool for the job is either a resin 3D printer –which can manage finer details– or an FDM (Fused Deposition Modeling) printer with an extra head dedicated to a dissolvable support material so I can be done with cleanup in minutes instead of hours. For now, the tool I have has a single printhead for a single filament, and that means tricky supports.
But tricky supports can stick. Both Twilight prints had issues with stuck bits under their manes, bellies, and to a lesser extent: their tails. The bottom layer of those respective regions appears to be peeling away with the interface material, so it takes a bit extra force – exactly the thing you don’t want around delicate parts like legs. While I was discussing this on the Sweetie Bot Project Discord server, user Equestria_dynamics suggested “increasing the contact layers between the print and the actual support material [2].”
Side Project
What fun is it to make all sorts of fun stuff if you can’t share it? You’d be surprised how hard that can be without access to a smartphone you’re willing to use (more on that in a future post when I install AOSP). Special thanks to my sister for loaning me her Nikon S3000 digital camera from around the time she got a smartphone. It’s mostly unused, but the charger was missing. I tracked one down and we ordered it up.
This camera is good for beginners and begging brothers. My impression is that it was aimed at people who understand the concept of point and shoot, but prioritize pictures fitting on a card over lossless compression methods. Read: I want .png and spent hours confirming it only does .jpg.
To get the best quality pictures I can of my prints, I’ve decided to get myself a photo booth. For an early prototype, my father laid some large sheets over his workbench and topped that with some parchment paper so the content on the other side wouldn’t show through. Presently, we’re making a second, more permanent version out of a cardboard box with some creative cutting.
Takeaway
As with any piece of software, Slic3r is taking time to learn. Having to learn a whole segment of the workflow all at once makes it take a bit longer, but I look forward to being able to show my stuff off in a more controlled manor than snapshots with random bits of house in the background.
Final Question
Have you ever glued delicate parts back together on a 3D print? What glue worked out for you?
Works Cited
[1] dragonator, “Mane 6 models MLP:FIM,” Thingverse.com, April 09, 2012. [Online]. https://www.thingiverse.com/thing:21076. [Accessed Jan. 17, 2022].
[2] E. dynamics, Sweetie Bot Project. [Discord] #3d-printing, (Jan. 14, 2022).