Introduction: 3D Print a Rock

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About: I'm a designer and art + design educator. I love shoes, philosophy, adventures, and making things.

Hello makers!

I'll be showing you how to 3D print a rock of your liking, starting with capturing it with 123D Catch, refining it using Meshmixer, and then setting it up for print using Cura. The original intention was research my architecture thesis, but this process can be used to replicate any object for 3D print.

You will need:

Step 1: Find a Good Rock

Pick a rock to your liking of any size, shape, or color.

For me I was interested in Scholar's Rocks. Visit: This Page for more information on Scholar's Rocks.

Step 2: Take 360° Photos of Your Rock

You can use 123D Catch through your iPhone. For better quality, I used my DSLR Camera and 123D Catch for Windows. If 123D Catch does not work for you, please try as an alternative: ReCap 360, here is their tutorial as well.

How to Take the Photos:

  • Take as many photographs as possible (about 30-50) of your object, so that 123D Catch can assemble a 3D model.

  • Try to keep the same distance away from your object, but still capture the object in its entirety.

  • Make sure to take a picture every 5-10 degrees, both straight on, from the top, and from the bottom

  • Do not use flash

  • Keep images clear and sharp

Step 3: Import the Photos, Then Export As .obj

Import:

Open the 123D Catch application, and click the button for "Create a New Capture". You'll get a dialog prompting you to select image files. Navigate to the folder where you put your photos, and select them all. The scene calculation can take some time, about 15 to 20 minutes.

Cleanup:

If everything goes well, 123D Catch will show you a 3D presentation of your object that you pan around. Click on the orbit icon on the tool bar, and you can look at your model from all sides. There will probably be things in the scene that are not part of your target object.You can erase these by selecting them with the lasso or square tools. Go ahead and clean up your capture by deleting anything that doesn't belong. When you are done, save your scene with another name.

Export:

Go to File/Export in 123D Catch, and choose .OBJ format for export. Save the file to folder with a descriptive name.

Step 4: Import .obj Model Into Meshmixer

If you need to tweak your model in any way, or feel the need to do any structural analysis, Meshmixer is a great software to do so.

Once you import to Meshmixer, you can start Sculpting under the Sculpt tab. Please play around and see what is to your liking.

Under the Analysis tab, two great tools I use are Inspector and Overhangs.

Inspector inspects any holes that are present, which is crucial to fixing before you 3d print. You can click on Auto repair all, or experiment to your liking. Under Overhangs, you can generate any supports that are needed. In 3D printing, it is a additive digital fabrication method. If the model has many overhangs without supports, it is wise to add them so there are no complications while printing. The supports can be easily removed with tweezers after the print is done.

Save your model as .obj once done.

Step 5: Print Your Rock

I will be using the 3D print software, Cura, for my Printrbot Simple. Open up Cura. Go to file, load model, and select the .obj you saved previously from Meshmixer. Each 3D printer is unique, and so will the settings. I suggest you visit your manufacturer's site to see which setting is suitable for your printer.

Cura also allows you do rotate, scale, and mirror the model to your liking. Please visit this link for a more detailed tutorial of the software.

Cura automatically comes with a test print robot, I suggest you print this test before proceeding with a long print .

Once the settings are complete, have fun printing! Please don't hesitate to comment with any questions or share with me your newly printed rocks!