Author: Shadow8472

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).

Good Morning from my Robotics Lab! This is Shadow_8472 and today I am continuing to work with my 3D printer. I’m covering a lot of ground this week, so let’s get started!

.Gcode Flavor

I left off last week wondering what was with my printer cooling its head when I had already preheated it through firmware. I reached out to various help channels until I randomly speculated that my printer was speaking a slightly different dialect than what PrusaSlic3r was feeding it. A helpful user suggested I switch my .gcode flavor to Marlin (listed as Marlin (legacy) in Slic3r).

I compared outputs from the two flavors after slicing the same object. The two files were similar, but legacy machines like mine –it would seem– do best with some additional information before any custom .gcode a user might want.

In retrospect, I probably should have learned to make my own temperature tower. Running .gcode meant for a larger printer can cause any one from a number of problems. At the same time, I’m glad I printed the tower with raw .gcode or else I might have easily given up.

Calibration Park

Armed with an optimal or near-optimal printing temperature, I set about printing a calibration multi-test [1]. I came back part way through the print and found that a PVC pipe I use to extend the filament holder had fallen off and both the X and Y had been gotten way off (I’m just glad it wasn’t on a more serious print). Additionally, the base was warped something awful. The test was still stuck to the printbed, but it was almost trivial to remove. I figured my bed was too low, which it was, but it took me until I noticed my heated bed turning off after the first layer that I had a setting wrong in Slic3r.

I was able to save my second serious attempt at the test by manually adjusting the temperature from my printer’s touchscreen. It turned out pretty well after that. The scratch in the middle of the bed was obvious, and a lot of the fine details in the lettering describing each test were lost. Otherwise, everything appeared to do OK at the very least. The overhang test was technically still together at the 80 degree inclination, but artifacts were beginning to show up by around 45 degrees. Most importantly: the large artifacts I had when unknowingly printing with wet filament were fixed.

Planning a Complex Print

To date, the most complex print I’ve successfully probably pulled off would have to be my Blinkie Pie case, where I modified a PacMan ghost case so a camera could see out one eye. Aside from a little impossible bridging that quickly evened itself out, that wasn’t a difficult print. But the world of 3D printing is much more diverse than variations on simple shapes.

I decided to try printing a model of unicorn Twilight Sparkle — both for her (percieved) relative simple geometry compared to her friends and so I wouldn’t have to risk her potentially breakable wings as seen across most of the show. I found a model on Thingverse after looking at several different places that wouldn’t let me download without creating an account — free or otherwise [2].

I went back and forth with it between Slic3r and Blender a time or two to refine Twilight’s model. While skimming through the planned layers, I noticed she had a sizable oral cavity. Her tongue and teeth were simple enough to delete, but it took a bit more patience to remove the rest of her mouth and stitch it back together. Somewhere in there I got rid of her eye lashes, which were also separate meshes from her main model as I was sure they would be hardly there to begin with and likely would be damaged while removing support material.

Speaking of support material, I knew from the beginning that I wasn’t getting away without a bunch of it. Twilight’s mane has a number of spots that hang down from layers printed later – let alone her tail as it arches up, backwards, and not quite to the ground. I messed with the automatic settings until I had what looked like a minimal amount of support, but after seeing the results of the overhang test, I put the settings back up. I also ordered up a raft three layers thick to cover up the scratch in the middle of my build plate.

Another concern I had was what Twilight’s center of mass was going to look like. At one point, Slic3r had her tail slotted for mostly solid infill with her head at 15% honeycomb infill. While I was able to find a solution involving analyzing the sliced figure with a Blender plugin, I ended up scaling Twilight up to about four inches as opposed to about three/three and a half – big enough so her tail was also rendered as a shell with infill, but small enough that her legs were solid.

A closer inspection of some supports gave me the distinct impression that Slic3r was being silly. The most complicated part of Twilight’s geometry is her mane, and there were more than a few tiny “overhangs” I figured would be fine being bridged instead of supported. I found some support blocker cubes I could move and scale, but it was clunky and there’s a better system for painting on supports I’ll be looking into next week. I wasn’t the happiest with the results I had, but I printed it anyway.

Cleanup and Repair

Between six and seven hours later, I had a pony standing on my build plate rendered in my recovered red filament. Cleanup started quickly as I cut away large sections where I knew there wasn’t anything, but as I got closer in, needle nose pliers and cutters were getting to be a little too awkward. My father arranged for a poker fashioned from some construction grade tie wire often used for holding re-bar in place while pouring concrete structures. Even then, it was a bit thick to fit in all the needed places. My mother offered a sewing straight pin which was versatile, but bowed more easily.

I quickly became jealous of dual+ head printers that can possibly use a soluble filament for easy support removal. It was a major morale boost when I was finally able to free Twilight’s face. Other tough spots included the arch of her tail, The tight spots between her legs and up across her belly, several tight spots in her mane, and the raft stuck to her hooves. I am very glad I scaled her up as much as I did.

There were a few moments when I wasn’t as careful as I should have been. I broke Twilight’s right back leg below her hock (the ankle-like joint most of the way up her leg) about half way through, and snapped her mane a few times in a couple places. Sections across her belly had to be cut away.

Despite the missing leg, there remains a piece just behind Twilight’s front legs. I had a feeling from the beginning that the supports between her forehead and bangs wouldn’t be coming out and they haven’t. At this point, I’d need to melt a handle to the remaining support material and carefully yank. The toughest holdout is physically trapped between her neck and the bit of her mane hanging to the side. I’ve already chipped the tip of her mane there trying to get it out.

I had already decided that I’d be reslicing and reprinting – I just haven’t yet. However, it doesn’t feel right to leave this Twilight without at least reattaching her leg and doing what we can with her mane. My father and I worked on the remaining bits of raft with a razor stuck to her hooves and used some superglue. The first repair on her mane didn’t go the best, so we’re using some painter’s tape to hold it in place. The leg was more promising, so at least she can stand while she waits. Maybe I’ll come back to her when I have more skill, but for now, this model has served as a learning experience so my next print should go better.

Side Project

I accidentally closed my main FireFox window. Normally that’s annoying, but since there was an update cued, I managed to destroy it completely in my attempts to recover it. I checked around online and learned a little about how Firefox stores saved sessions and I found a backup from not quite two weeks ago. It’s not perfect, but I’ll take 96% restoration over nothing!

Takeaway

3D printing is an art form, even if you’re printing other people’s .stl files. There are many factors to adjust to keep your printer in top condition. Slicing programs require knowledge about your printer’s tolerances to use effectively. Even if it prints correctly, you may want to sand, prime, and paint it.

Final Question

Have you ever set aside a work-in-progress for when you’re better equipped to finish it?

Works Cited

[1] majda 107, “*MINI* All In One 3D printer test,” Thingverse.com, Feb. 25, 2018. [Online]. Available: https://www.thingiverse.com/thing:2806295. [Accessed Jan. 3, 2022].

[2] dragonator, “Mane 6 models MLP:FIM,” Thingverse.com, April 09, 2012. [Online]. https://www.thingiverse.com/thing:21076. [Accessed Jan. 3, 2022].

[2*] David, “Mane 6 models MLP:FIM – Fixed,” Thingverse.com, June 19, 2012. [Online]. Available: https://www.thingiverse.com/thing:25282. [Accessed Jan. 3, 2022].

* The second [2] hosts the same models but “fixed” variants. I don’t know for sure which version I used, but I’m slightly more sure than not that I used the 21076 models.

Good Morning from my Robotics Lab! This is Shadow_8472, and today I am recalibrating my 3D printer after leaving things to rot for a year or so. Let’s get started!

Printer Alignment

The first step in getting my printer operational again was to start from the beginning: alignment. My father got out the bubble level and I folded some large papers to get the plethora of degrees of freedom all lined up.

Tuning continued with the built-in, poorly communicated bed leveling tool. The printhead traveled to each corner and I slipped a calibration sheet under it and adjusted the corners such that it could slide, but not freely. When the right Z-axis was found to be misaligned, my father reached in and turned it a bit. I was sure it would have been frozen, but we were able to level the horizontal bar.

Temperature Tower

One well-used calibration test is the temperature tower. Regular printers use ink/toner (which original manufacturers go to great lengths to regulate) and paper (which is so standardized, it’s rare to see messed up). 3D printer filament is at least as varied and presents itself as universally interchangeable as long as it fits and the printer can melt it. As a result of differences between specific models –and even specific printers/printing environments– filament and printer manufacturers can only make broad guesses as to what the best setting will be for your specific printer.

That is where the temperature tower comes in. Instead of printing the same test shape over and over again on different jobs, they can be stacked one on top of the next and an instruction to change printhead temperature for each “floor” can be inserted.

From what I’ve gathered, temperature towers are normally assembled manually in a slicer for the exact printer, but I decided to try one straight from gcode (that went hot to cold; I didn’t want the filament freezing on the bottom and making a mess trying to print atop thin air). I didn’t first make sure the printer would be able to understand it; I didn’t make sure it would fit within my printer’s volume. I just loaded it up and hit print. Surprisingly, it worked. I had adjusted my bed a bit high and the first layer was smooshed (making it very difficult to remove), but I’m officially printing again.

I used my red filament and the tower that came out demonstrated its ability to bridge, overhang, and produce fine points. Each floor is numbered after the temperature it was printed at. The whole range was fairly good, but there was less stringing higher up, where the printhead was cooler. All other tests performed well at most temperatures.

Side Project

This month’s effort to reward award goes to getting my father printing on Debian. I sat down with him to get it working and we installed the CUPS universal printer driver and it worked with no additional fiddling.

Takeaway

Printer calibration is an important step to understand and use when needed – 2D or 3D. 3D printing is a much younger technology with a literal extra dimension for things to go wrong; it requires a greater degree of technical mindedness to keep in working order to the point where you at least need to be or know a hobbyist to have continued access to this amazing consumer level technology.

Final Question

I had more planned in terms of printer calibration, but it looks like that will need to wait for next week as I figure out the thought process for PrusaSlicer. It looks like they have some sort of preheat function in the .gcode header, but in practice, I already preheat my bed and hot end before selecting a file to print. In my workflow, this programming blurb ends up telling things to cool. Any ideas where the setting is to control it?

Good Morning from my Robotics Lab! This is Shadow_8472 and today, I am getting back into 3D printing, but I doubt it’s going to be pretty. Let’s get started!

Inspection of Equipment and Materials

My 3D printer is in used condition. The print bed is scratched and one of the two Z-axis rods got bent at around the same time. My filaments are old and brittle. I can’t even use the slicer it came with anymore because it’s both outdated and made exclusively for Windows. I’d rather just start over with a standard one designed to be user-serviceable. But that’s not an option at the moment.

I should learn about what I already have and work from there. There’s not much I can do about the scratch unless the original replacement pad shows up or unless I’m willing to fill it in/cover it up somehow. As much as I’d like to replace the Z-axis rod, a suitable replacement proved elusive for reasons discussed above; besides, the tweak doesn’t look that bad – the top of the rod only moves back and forth a little when the print print head is moving vertically and is down low. Alternate slicers exist. Long story short, I may as well give this printer one last chance before giving up on it completely.

Filament Reclamation

I have two PLA filaments I’m considering today: my original, red one and an opaque white one I got later and hardly ever used. Red used to just work. White felt different from its day 1 and never printed nicely. After a couple years of absorbing moisture from the air, they’re both as stiff as spaghetti. I even bent one piece of White until its middle piece snapped out from between the ends.

Besides causing stiffening, absorbed water evaporates when exposed to heat, causing problems such as the ones I experienced last time I tried printing. Water from within the filament forms steam, and it’s the steam that causes mysterious jams that seemingly go away come time for diagnostics.

A number of places have listed methods for drying out filament: bake it. Just be aware of the material’s glass transition phase where it goes from resembling a wire to resembling a more squishy rubber. The whole spool will fuse and you’re reclamation efforts will be for none. For PLA, that transition is somewhere around 140 degrees Fahrenheit.

To be safe, I elected to aim for 100-120 degrees F. My stove at home doesn’t hold its temperature that low. We put a bowel of water in overnight with a rising loaf of bread and it tested way cooler than needed. We tried our old toaster oven and tested at 125 F – close, but as I only had one shot to fix what I have, I didn’t want to risk it.

Specialized devices exist to dry out filaments. I was able to approximate one by modifying a food dehydrator operating at 125 F. My final design involved a rheostat from my father’s soldering iron to adjust the otherwise fixed temperature, some Duplos (a Lego-like block aimed at younger ages we’ve had laying around since I was little) to hold up the lid, and a tall, plastic film from my mother’s cake supplies to extend the tray. Without a thermostat, I monitored the temperature myself with a digital cooking thermometer we got for my sister’s bread making.

Both Red and White were dried overnight. White still felt stiff, so I left it in for several hours more. The temperature was difficult to keep constant. I left the contraption in a small room, and the room warms up and I have to turn the power down. If I had known how to easily, I would have built a thermostat capable of operating in those ranges. In retrospect, it would have been better to just leave it in the toaster oven on warm and not worry about it.

Side Project

I was able to get Vaultwarden running by forwarding the incoming traffic to the container’s port 80 instead of 443. However, this is still sub-optimal. I have my ability to manage passwords between devices back, and that feels sooo good after months of downtime, but I’ve been strongly encouraged to use a reverse proxy. This week, I looked into NGINX, and I believe that will be a focus some time in the coming weeks.

Takeaway

The path to my improvised filament dehydrator was a little longer than going right there. My early approach was At first, I figured I’d want to build something with a couple appliance bulbs like what the oven uses. The food dehydrator I eventually used as a base only has an on-off switch, so to lower its steady state temperature, I used some short Duplo stilts to raise a lower level to let ambient air in. I kept them for my production run, though if I have to run it again in the future, I’ll leave the sides closed and turn the power down lower on the rheostat.

Final Question

What would you tell someone who is ready to know more about 3D printing than: use slicer, level bed, load filament, press start?