Recent 3D Printing
After several years without one, I got a new 3D printer in 2024. This post explores what I've been doing with it.
At the start of last year, I got an Ender 3 V3 KE. However, it didn't work initially. I had an issue basically the same as described here: during the first-time calibration it kept failing at the point where the nozzle pushes down on the plate. Customer support sent me a replacement strain gauge and that didn't work. After months of troubleshooting (not a tonne of time in total, just spread out to odd evenings and weekends when I had the chance to work on it), what finally got it working was re-seating all the cables between the strain gauge and the main control board. One of them must have had a poor connection and the expected signal was absent—which certainly matches the observed symptoms—because it has worked fine ever since.
After that, I've been able to print a bunch of stuff: a mixture of my own designs and ones I've downloaded, and ranging from toys to useful items.
When it comes to my own designs, I have a general workflow that I made a short video to demonstrate. The part in this video, a plastic bushing for a manual coffee grinder, took less than 10 minutes to print (the design process took a bit longer, but even it went pretty fast) and successfully fixed the grinder.
Dollhouse Furniture
Last year for Christmas I built a dollhouse (actually instead of dolls it mainly gets used with Calico Critters bunnies). The 3d printer has provided a source of furniture and accessories (not the exclusive source though) for this dollhouse. Some of this is my own design, namely a canoe, bookshelf, and floor lamp. I've also printed some other designs I've found, such as a wardrobe (in addition to storing their clothes, the bunnies can go to Narnia, after we read it) and a mini 3D printer (scaled down and deleting some layers of nesting from this model). Some of these things have been my elder daughter's request, including the 3D printer which impressed me by her creativity. I guess it's not too early to start teaching about recursion or maybe even von Neumann machines, haha.
Sundials
I also made 2 sundials. One was from following this tutorial. The other was my own design. Aside from working through the tutorial, I did some reading on Wikipedia to understand the theory well enough to come up with a working design. Here are some excerpts describing different types of sundials:
The most commonly observed sundials are those in which the shadow-casting style is fixed in position and aligned with the Earth's rotational axis, being oriented with true north and south, and making an angle with the horizontal equal to the geographical latitude.
On any given day, the Sun appears to rotate uniformly about this axis, at about 15° per hour, making a full circuit (360°) in 24 hours. A linear gnomon aligned with this axis will cast a sheet of shadow (a half-plane) that, falling opposite to the Sun, likewise rotates about the celestial axis at 15° per hour. The shadow is seen by falling on a receiving surface that is usually flat, but which may be spherical, cylindrical, conical or of other shapes. If the shadow falls on a surface that is symmetrical about the celestial axis (as in an armillary sphere, or an equatorial dial), the surface-shadow likewise moves uniformly; the hour-lines on the sundial are equally spaced. However, if the receiving surface is not symmetrical (as in most horizontal sundials), the surface shadow generally moves non-uniformly and the hour-lines are not equally spaced;
The distinguishing characteristic of the equatorial dial (also called the equinoctial dial) is the planar surface that receives the shadow, which is exactly perpendicular to the gnomon's style. This plane is called equatorial, because it is parallel to the equator of the Earth and of the celestial sphere. If the gnomon is fixed and aligned with the Earth's rotational axis, the sun's apparent rotation about the Earth casts a uniformly rotating sheet of shadow from the gnomon; this produces a uniformly rotating line of shadow on the equatorial plane. Since the Earth rotates 360° in 24 hours, the hour-lines on an equatorial dial are all spaced 15° apart (360/24).
In the horizontal sundial (also called a garden sundial), the plane that receives the shadow is aligned horizontally, rather than being perpendicular to the style as in the equatorial dial. Hence, the line of shadow does not rotate uniformly on the dial face; rather, the hour lines are spaced according to the rule, tan (hour_line) = sin (latitude) tan (15 deg x t); t = hours before or after noon
All the hour-lines intersect at the point where the gnomon's style crosses the horizontal plane. Since the style is aligned with the Earth's rotational axis, the style points true north and its angle with the horizontal equals the sundial's geographical latitude L
In polar dials, the shadow-receiving plane is aligned parallel to the gnomon-style. Thus, the shadow slides sideways over the surface, moving perpendicularly to itself as the Sun rotates about the style. As with the gnomon, the hour-lines are all aligned with the Earth's rotational axis. When the Sun's rays are nearly parallel to the plane, the shadow moves very quickly and the hour lines are spaced far apart. The direct East- and West-facing dials are examples of a polar dial. However, the face of a polar dial need not be vertical; it need only be parallel to the gnomon.
The surface receiving the shadow need not be a plane, but can have any shape, provided that the sundial maker is willing to mark the hour-lines. If the style is aligned with the Earth's rotational axis, a spherical shape is convenient since the hour-lines are equally spaced; the sundial is equiangular.
In the equatorial bow sundial, the gnomon is a bar, slot or stretched wire parallel to the celestial axis. The face is a semicircle, corresponding to the equator of the sphere, with markings on the inner surface.
The key common features in the geometry of a sundial are:
- The shadow-casting gnomon is at an angle to the ground equal to the latitude; this makes it aligned with the rotational axis of the earth.
- It should also point north (in the northern hemisphere)—at night the elevation angle and direction should aim towards Polaris.
- The sun appears to rotate around this line (of course it's really the earth that is rotating) every day: 360 degrees in 24 hours or 15 degrees per hour. This determines the spacing of the hours marks, with trigonometric corrections if the alignment of the receiving plane calls for them.
- More advanced sundial design might do something with the analemma.
Other
Other things I've used my 3d printer for are:
- A cellphone case. It cracked when I dropped my phone, so I should re-print it. A cheap sacrificial case is a really handy thing to be able to print on demand.
- A little model of a turbine. Put it on an axle and run tap water through it and it spins pretty fast.
- A cookie cutter in the shape of a candle
- I did some stocking stuffers for various family members. A lot of these were designs I just found online and downloaded, but I did a few custom designs: a "Baby's 1st Christmas" ornament; a cable car/gondola/funicular for a Christmas village (it's 1:48 scale so it would work for model railroads too); a bookend (I did this design years ago, but printed a new pair this Christmas).
- A stamp with the "Five solas" of the Reformation. As I wrote in the Thingiverse description,
This was inspired by the influence of the printing press (moveable type was key, and this has fixed type, but whatever) on the Protestant Reformation. Attach it to a backing, ink it, and you can stamp the five "sola" statements of the Reformation.
(The impact of the printing press has come up in a lot of what I've read recently, from Marshall McLuhan, to some books about the history of industry—a post on that is sitting in my drafts—to one I'm reading right now about the history of knowledge by Simon Winchester).
Future Plans
I have several ideas for things I want to try 3d printing in 2025. For one, I expect I'll continue to make some toys, whether that's more dollhouse furniture or other stuff like a spirograph. In the useful category, perhaps a cupholder for our stroller. I've seen some designs for models of jet engines that look pretty cool; and I'd like to try making a design for an astrolabe (I like measuring, calculating, and navigating instruments in general) at some point. I might also re-visit this design (from this post) to see if I can improve it.
If you enjoyed this post, here's a couple from the archives I also recommend: