Introduction: 3D Printed Optical Illusion: Penrose Steps

Things aren't always as they seem. I have always been fascinated with optical illusions and their ability to cause people to double-take and really pause to see how they work. In todays Instructable, I teach you how to create the iconic Penrose Steps which were conceived by father-son duo Lionel and Roger Penrose, and also featured in the movie Inception. The Penrose steps, when viewed at the proper angle, appear to create an infinite upward staircase with no obvious beginning or end. Let's learn how to create this mind-bending Illusion. Anyone can do it, so let's get to it!

Step 1: Assembling the Materials

Good news! It doesn't take much to create these Penrose steps! Here is what you'll need:

- Access to a 3D Printer with PLA filament *If you don't have one, you can find someone online (like etsy or something) that can print files for you and then send them to you* Filament can be found here

- 3D Modeling Software (I will supply the files to you but it is good to get so you can start to learn)

- Gray Primer

-White Spray Paint

That's it! Let's get to it!

Step 2: Tips to Start 3D Printing

Before I turn the coveted files over to you, I want to spread some wisdom from what I have learned in the couple of weeks from 3D printing to the aspiring person who wants to get into 3D printing (as an inexperienced 3D printer myself).

Tip #1: Get a really good reference photo.

Unless you are creating something yourself, you will want a really good reference photo to build your model from. Especially with optical illusions, it can be terribly difficult to visualize unless you have an example in front of you to reference.

Tip # 2: Create a rough sketch from your reference photo and measure it.

What I have found useful is when you have found a reference photo, sketch it out as good as you can and then measure out your drawing so you can keep your units consistent. Also, actually measuring it out will make the 3D modeling process will go much MUCH faster.

Tip # 3: Practice using the hotkeys and built in functions.

Learning the ins and outs of the hotkeys in fusion like R for rectangle, L for line, C for Circle, E for extrude etc. will save you monumental amounts of time. Also, instead of building things over and over in meticulous detail, you can take advantage of the Mirror or Revolve functions that can do those things in a fraction of the time.

That's the food for thought now lets get the food!

Step 3: Penrose Steps

I quote Spongebob when I say, "Well, here ya go.." These are the STL files for the Penrose Steps. I have included some pictures to show you what the incremental 3D modeling looked like. It was pretty straightforward with the hardest parts being, like I said before, just visualizing how it was going to come together. You will need to upload the files to a 3D "slicer" respective to the 3D printer you are using. For example, I have been using Cura to orient my files and then ultimately upload them to a Luzbot Taz 6 3D printer that I am lucky to have access to. If you have someone printing these things off for you, disregard what I just wrote and simply send it to the person you have printing for you. If not, I highly recommend printing support structures to avoid "sagging" in the 3D print. It will take longer but it will be well worth it.

Step 4: Painting and Detailing *Optional*

[This doesn't have to be done to grab the fascinating effect of the penrose steps. However it will absolutely enhance it. If you choose not to paint etc, you are done!] Once the Penrose Steps are printed out, you will want to spray on some primer and then coat it with white spray paint. Feel free to get creative with the colors that you choose! When you are done you can really see this Illusion come to life!

Step 5: Finished!

Now display the Penrose Steps for your friends and family to see! Be sure to point out the "sweet spot" where the stairs seem to go on infinitely. Also, feel free to play around with different "Infinite staircase" designs online. I also painted it gold for fun! :p If you enjoyed this Instructable, please leave a like, a comment and if you make it, let me know, I would LOVE to see what you come up with! Thanks for checking out this Instructable! Can't wait to do the next one!

Check another cool 3D printing Instructable project (with file) here:

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