"If you’re not spending 5 hours per week learning, you’re being irresponsible"
To that end I decided to learn something. In this case I wanted to start to understand CAD (OpenSCAD) and had a need.
I had seen one of the arrow illusions on Facebook and wanted one. Thingiverse was there to support me once again at https://www.thingiverse.com/search?q=arrow+illusion&dwh=635b840b078ed87
The issue was that after a few prints to get it acceptable, I had a really cool "Rock". I wanted to be able to share the wonders of this illusion with the world so needed a way to present it.
DID YOU KNOW THAT "NECESSITY IS THE MOTHER OF EDUCATION"?
Armed with a need and the tools needed to do something about my dilemma, I googled "hole in cube openscad" and landed on an example.
I have always felt that "Software is Software, once you understand the Syntax" and this was really an example of that. I was able to really start understanding how to utilize basic shapes, variables, scripting, relational placement and a bunch of other stuff.
Since I kind of liked the outcome, I wanted to share.
The tolerances are tight to achieve the best performance (I let Molly and Buster toss one around for a while and after washing off the dog spit, minus a few teeth marks it was none the less for wear).
Since layers, printers, etc. can make a difference, in addition to the STL of individual parts and one of the whole shebang, I have also uploaded all of the SCAD stuff I did to allow you to tweak if needed (Did I mention I made them all usable in Customizer on Thingiverse or in OpenSCAD?). You can change almost all dimensions of the Bars, Gears, and Spindles (another Hint: The bottom bar is just the top bar with no text and the ovals and wings set to zero (0) ). The text is configurable as well if you want to play.
Hint: If you decide to make one, the bottom bar makes a great tool for pressing the small gear on to the third hub of the "Long Spindle". It is tight on purpose as is the fit of the fifth hub into the arrow.
For me I used the following settings in Cura
.3mm First layer
.2 mm layers
Supports are need for the arrow
Z-step Retraction on (Over parts)
most the other stuff was default
ADDITIONAL PARTS: 8 ea. 4-40X1/4 screws that can be easily self-threaded in to the spacers.
Just feeling good about figuring some stuff out
the washers are meant to be a rudimentary bearing and you will want to have one, maybe two placed on top of each gear between the gear and top bar. This is a bit of a bushing to provide vibration dampening, friction relief, etc.
And I wanted to give credit for the gears that were remodeled from here https://www.thingiverse.com/thing:2830690