Left Pointing Arrow Illusion with Support Tear-away Tabs and a Stand

cults3d

Behold! Just when you thought there could be nothing as amazing as the Rightward pointing arrow ... I present to you the left pointing arrow illusion! Okay, all hype aside, of course it's just a mirror of the rightward pointing arrow. However I have added support tear-away tabs to the model and have created a stand for the arrows. The support tear-away tabs make support removal very easy. They're designed to be used with the supports interface feature of Cura or similar feature in other slicers. If you're not familiar with the support interface it's essentially a raft for the model that is built at the top of the supports, but instead of being flat like the raft it is contoured and shaped the same as the bottom surface of the model. It's an excellent feature, but if you set the support Z distance fairly small to get a smoother surface, it's almost impossible to remove the supports. These tabs extend the support interface out from the model and provide an area to grab onto to tear away the supports from the model. The tab structures also have a full height tower to increase the time between layers so that the tiny top layers don't print too rapidly and end up being smeared around because of insufficient cooling time. I've included the model with and without the supports tabs, and also the right pointing arrow with the tabs. If you want the right pointing arrow without the tabs, you can get it from the original thing. There's also a video there showing how the illusion works. The stand has a spherical capped reuleaux triangle base. The diameter of the post is 4.7 mm and the hole in the arrow has a diameter of 5.0 mm, so it has a 0.3 mm tolerance for fitting. Scale the stand up or down as you please if you think your printer can handle a tighter tolerance or if you think it needs to be looser. Thanks to Dr. Kokichi Sugihara, a professor at Meiji University in Tokyo, who created the right pointing arrow illusion as part of his research into the new field of “computational illusion”. You can read some more about his creations here and here. And thanks to Andraxis for creating the model from which this is remixed.