Complex Forms in Tinkercad
Designing for 3D Printing in Parts.
Tinkercad is a powerful software that allows users to create all manner of 3D objects. It is even more handy that Tinkercad is optimized for 3D printing using desktop 3D Printers! However this does not mean that anything you make in Tinkercad will print cleanly or otherwise look how it is supposed to when it is printed. 3D Printing is basically the same as 2D printing over and over again, so 3D objects that are meant to be printed must consider that they will be printed from the bottom up in many tiny layers. One major consideration is Overhang. Any part of a 3D model that is not supported by something underneath it, must print with scaffolding called support materials, that have to be broken off once the object is done printing. You can see the support materials being built into the model in the picture below:
As you can see in the image above, the lantern has support materials under every arch and in every place where there is overhang, such as the circular openings for the light box, and the middle of the lantern where it curves inward, as well as the bulbous ornament on top of the cap. Since the cap has so much overhang, it makes more sense to place it on the ground next to the lantern body, so that support materials are minimized. You can design all sorts of things in Tinkercad, but remember that it is sometimes best to break your model into parts so that it prints cleanly.
Sometimes you have to print a model to see where the printer will add support materials. After I printed and assembled the first version, I made changes to the design so that I could put a light in the box, and a battery in the base. To do this, I created a vertical hole through the lantern and a separate top piece that snapped into the lantern cap and connected it by snapping into the light box. I made separate pieces for the base that the lantern body could snap into, and a cap to hold the battery inside the base.
It took a couple tries to get the measurements exactly right. Even when you measure parts like the Battery and LED light before you build it, each Print might be slightly different than what you design in Tinkercad, so it is a good idea to build in a little extra room for parts to fit together - making some holes slightly bigger than the parts that are supposed to fit into them is a good start - but sometimes you have to do a test print or two to figure out how much is enough and how much is too much. Here is my finished lantern lit up with a Battery and LED light.