By Rachel Dallman

I have recently been experimenting with 3D printing using the ETC Lab’s MakerBot Replicator Mini, printing different open-source models I found on Thingiverse. I wanted to start printing my own models, but found traditional full-scale 3D modeling softwares like Blender and Autodesk Maya to be intimidating as a person with minimal modeling or coding experience. In my search for a user-friendly and intuitive modeling platform, I found Tinkercad – an extremely simplified browser-based program with built in tutorials that allowed me to quickly and intuitively create models from my imagination. The best part about the program, for me, was the ability to import and extrude vector designs I had made in Illustrator.

Tinkercad’s easy to use Interface

For my first project using this tool, I decided to make a stamp using a hexagonal graphic I had made for the ETC Lab previously.

My original graphic is colored, but in order to extrude the vectors the way I wanted to, I had to edit the graphic to be purely black and white, without overlaps, meaning I needed to remove the background fill color. I also had to mirror the image so that it would stamp the text in the correct orientation (I actually failed to do this on my first attempt, and ended up using the print as a magnet since it would stamp the text backwards).  I’m using Illustrator to do all of this because that’s where I created the graphic, but any vector based illustration software will work (Inkscape is a great open source option!). You can also download any .SVG file from the internet (you can browse thousands at https://thenounproject.com/ and either purchase the file or give credit to the artist). If you’re confused about what parts of your image need to be black, it’s helpful to imagine that all of the black areas you create will be covered in ink. Below is a picture of what my image looked like in Illustrator after I had edited it.

To do this, I started by selecting each individual part of my graphic and changing the fill and stroke color to black, and removed the fill from the surrounding hexagon. To reflect the image, I selected everything and clicked Object > Transform > Reflect. My stamp-ready file looks like this:

In order for Tinkercad to read the file, I had to export it in .SVG format by going to File > Export > Export As… and choose .SVG in the drop down menu. If you’re doing this in Illustrator, you’ll want to use the following export settings:

I then opened Tinkercad and imported my file. Much to my dismay, when I first brought the .SVG file into Tinkercad, it couldn’t recognize the file format, meaning I had to do some digging around online to figure out what was going on. I found that the problem was with the way Illustrator exports the .SVG file. I had to add in a single line of code to the top of the file in order to solve the problem. The problem is that Illustrator is exporting the file at .SVG version 1.1, and Tinkercad can only read .SVG 1.0, so I had to manually revert the file to the previous version. I downloaded Atom, an open source code editor and pasted in the following line of code at the very beginning of the file and saved it. This step might be irrelevant to you depending on the software you’re using, so be sure to attempt importing the file into Tinkercad before you change any of the code.

<?xml version="1.0"?>

I then imported the updated file, ending up with this solid hexagon. This was not what I wanted, and I assumed that Tinkercad was simply filling in the outermost lines that it detected from my vector file. Apparently, the price for the simplicity of the program is one of its many limitations. 

After I noticed that it was possible to manually create hexagons in Tinkercad, I decided to go back into Illustrator and delete the surrounding hexagon and then simply build it back in Tinkercad after my text had been imported. Depending on the complexity of your design, you may decide to do it like I did and build simple shapes directly in Tinkercad, or you may want to upload multiple separate .SVG files that you can then piece together. This is what my new vector file looked like after I imported it.

Next, I wanted to make the base of the stamp, and a hexagonal ridge at the same height of my text that would stamp a line around my text like my original vector file. To do this, I selected the hexagonal prism, clicking and dragging it onto the canvas. I then adjusted the size and position visually by clicking and dragging the vertices (hold Shift if you want to keep the shape proportionate) until it fit the way I wanted it to. I then duplicated the first hexagon twice by copying and pasting. I then scaled one of those hexagons to be slightly smaller than the other and placed it directly on top of the other, until their difference was the border size that I wanted. I then switched the mode of the smaller hexagon to “Hole” in the righthand corner, so that my smaller hexagon would be cut out of the larger one, leaving me with my hexagonal border. Next, I positioned the hollow hexagon directly on top of the base, and extruded it to the same height as my letters, so that it would stamp. For precise measurements like this, I chose to type in the exact height I wanted in the righthand panel. My final stamp model looked like this:

Then, I downloaded the model as an .STL file, and opened it in our MakerBot program and sized it for printing. Around three hours later, my print was ready and looked like this:

 

As you can probably tell, the stamp has already been inked. While my print turned out exactly the way I planned it to, I found that the PLA material was not great for actually stamping. On my first stamp attempt, I could only see a few lines and couldn’t make out the text at all.

 

I assumed that the stamping problems had something to do with the stamp’s ability to hold ink, and the stiffness of the plastic. I decided to sand the stamp to create more grit for holding ink, and tried placing the stamp face up with the paper on top of it instead, allowing the paper to get into the grooves of the stamp. This process worked a bit better, but still didn’t have the rich black stamp I was hoping for.

 

Because of this difficulty with actually stamping my print, in the end, I actually preferred my “mistake” print that I had done without mirroring the text, and turned it into a magnet!

 

This process can be applied to any project you can think of, and I found the ability to work in 2D and then extrude extremely helpful for me, as I feel more comfortable in 2D design programs. Tinkercad was simple and easy to use, but its simplicity meant that I had to do a few workarounds to get the results I wanted. I’m still troubleshooting ways to make my stamp “stampable”, and would appreciate any ideas you all have! As always feel free to come explore with us for free in the ETC Lab by attending Friday Open Hours from 10:00am to 4:00pm, or email etclab@umn.edu for an appointment.