This Thing is an OpenSCAD design which allows one to parametrically design pieces of chain mail. The dimensions of the links and the size of the overall patch can be adjusted.
When printed in PLA, the resulting pieces have an appealing 'tinkle' sound when manipulated. They also provide a pleasing tactile sensation which has shown to be enjoyable to a wide range of people. Manipulating a piece of it has been described as relaxing and satisfying.
It is a modification of Revar's wonderful design that has had the links rotated by 45 degrees. This causes the printed model to not have links on the corners which are linked to only one neighbor. It has the further benefit of allowing the Thing to fold parallel to the sides instead of diagonally.
Long strips can be printed diagonally across your print bed to make bracelets and necklaces.
For the brave, the model can be scaled down by half and printed with a 0.2mm nozzle.
This print is a good test of your printers small bridging ability, bed adhesion, and retraction tuning. The small bed contact area can make first layer adjustment difficult. The small bridges on the upper part of the "H" provide a good opportunity to adjust your bridging speed, fan settings, and bridge flow ratio. The small "pillars" between the two "H" sections require your retractions and temperature settings to be well tuned to avoid stringing and blobbing. Additionally, your over/under extrusing needs to be well tuned to ensure a smooth upper surface.
My example print settings are (using Slic3r):
0.24mm layer height
3 perimeters, 2 bottom, 3 top
First layer speed of 20mm and width of 0.55.
Perimeter of 0.7mm at 15mm/s and external perimeters of 0.45 at 15mm/s
Don't even think of using support. Infill isn't necessary as the perimeters are sufficent for the task due to the small cross sectional size.
Little work is needed after printing unless you ended up with string on blobbing on the small "posts" between the "H"s. If you had some, you may need to flex it a little to break loose the strings and some of the blobs. If the blobbing is very bad, you may choose to use a hobby knife to clean some of them off. Great care is necessary in doing so as this is detail work which can lead to slips and accidental cuts. Please use necessary precautions!
Overview and Background
This Thing is a program written in OpenSCAD which generates a 3D model of a piece of chain mail armor. A few pre-generated STL models are included to make it immediately useable for those without OpenSCAD or the time and knowledge to us it.
Lesson Plan and Activity
OpenSCAD can serve as a scientific and engineering learning device in conjunction with this model. There is a good deal of basic mathematics (through trigonometry) involved with the design and customization.
The model, when printed can be use for a variety of purposes. It can be used as a 'prop' when discussing medevial armor and weapondry.
The model also has the property that is is nearly impossible to produce with any other manufacturing technique other than FDM (Filament Deposition Modeling) which can serve as a focus for a lesson on suitability for manufacturing or DFM (Design For Manufacturing).
Printed examples of this model (and especially ones customized to desired dimensions) can be used in art projects to add texture and flexability to a wide range of designs. The ability to print it in different colors alows it to enhance the visual range of expression of created works.
Manipulating a printed version of this Thing provides a unique tactile and auditory stimulus which can be used for those with attention and sensory issues. Unlike some "fidget" devices, its use is minimally distracting and less simply repetetive.
PLA capable 3D printer
This Thing is easily printed even with the simplest of 3D printers capable of priting in PLA plastic--which is likely the most common 3D printing material in the hobby market. No other preparation or materials are needed.