MakerBot Industries

Heart Gears by emmett (Opened in Wings3D)

While MakerBot Operators are more than happy to print the thousands of incredible objects posted to Thingiverse, eventually many catch the design bug and reach out for guidance for how to get started designing models.

Your mission: to create a solid, manifold (“watertight”) STL-formatted file for importing into ReplicatorG. STL, created as the format for stereolithographic CAD files, is a ubiquitous format, so the design application options are vast. ReplicatorG also offers experimental OBJ and Collada file import capability — though the files are then converted into STL files. (You can open dozens of file formats in MeshLab, netfabb Studio Basic or similar 3D swiss army knife tools — and then export as binary or ASCII STL files, opening up even more models to ReplicatorG.)

Choosing Your Hammer

8-bit Heart by schmarty (3DTin.com image)

For design software, there are many powerful free and open source design tools for us to introduce to Operators. Favorites include 3dtin.com, Sketchup, OpenSCAD, Wings3D, and Blender. We have heard about but not experimented much with POV-ray (excellent tutorials here), FreeCAD, HeeksCAD, and Art of Illusion — apps that have serious fans in the 3D printing world.

Plastruder MK5 Solidworks 2011 Model by kai

For commercial solid CAD apps: Rhino (Mac users — jump on the free beta), Autodesk Autocad, Inventor, Creo, and SolidWorks are probably the biggest players in the field. But perhaps you don’t have upwards of $1k to spend on design software? Try the highly-capable $99 Alibre Personal Edition, Cheetah3D (mac only), or bonzai3d.

Below the fold is a handy five step exercise for brand new designers to get their feet wet with 3D modeling.

On the Mark, Get Set…

Here’s a learning scaffold I recommend for the pure design n00b.

Go!

Grab an object in the real world you can drag over to your computer (a coffee mug works great). Launch a browser and go to 3dtin.com and build a model of your object, construct it out of simple building blocks(“voxels”). (We have tricks for using this tool here and here. When you are done with your model, export it as an STL file. (And while you are at it, why don’t you take advantage of the option to save it directly to Thingiverse?)

You aren’t done yet! Take your exported STL and bring it into ReplicatorG. Skein and print it out, taking advantage of the simple STL manipulation tools in ReplicatorG to scale the object, orient it on the platform so as to minimize overhangs. Make sure to use the Move > Put on Platform tool to make sure that your model is firmly seated on the ground. Even if you feel your model is hideously ugly, print it anyway. It is tempting to judge results by computer visualizations of models — but the printed results may well teach you different lessons than you expect. And you aren’t done with this model, anyhow.

Level two!

Download and install Wings3D, a powerful subdivision modeler. You will be able to import the STL you created in 3DTin into Wings3D and view it from all angles. Now, familiarize yourself with the process of selecting points, lines, faces or entire objects and experiment with the range of tools available, deforming elements of your original model. There is a Defined Hotkeys pane in the Help menu that will help you get started.)

You may find yourself initially frustrated that every change you make is either too pronounced or barely noticeable, but as you accostom yourself to restricting motion to a single axis or range of adjustment (as well as locating tools for adding additional vertices and edges to the model), you will gain more nuanced control.

After hacking on your original model for a while, export an STL of the changed version with a new name. (Why don’t you login to Thingiverse and add this second model as an STL to the 3DTin thing you put up earlier?) You know what you have to do with it: print it!

Level Up: Level Three!

Now start a new empty file in Wings3D, and attempt to recreate the same model from scratch using whatever methods of manipulation work best for you.¹ Don’t be afraid to bruteforce it with only a few design tools at your disposal (Move, Extrude and Cut, for example, will get you very far). It is better to get your hands into the design process than to wait until you have “learned everything about the program.”

Level Four: Parametric Bonus Round

Join the OpenSCAD parametric design revolution by following MakerBlock’s excellent OpenSCAD tutorials. MakerBot’s own
Marius Kintel now maintains this project and has been hard at work extending and improving this useful app. Even if you don’t plan to design with parametrics in mind, exposure to this tool via the tutorial series will teach you quite a bit about 3D modeling and the power of constructive solid geometry as a design concept, applicable to any number of other programs. You will be able to export STLs during the tutorials. What do you do with them? Print them.

Round Five: Reflection Round

Now take stock: what is working about your handful of models? What prints improperly (or not at all)? There is a real advantage to 3D printing with a MakerBot: you can always print the model many times, cheaply and without much fuss. Take the information you have learned from your print back into your design work and continue to explore.

Now that you have jumped in enough to get a basic sense of the tools² you are ready to hunt for tutorials and blog posts to help you learn how to do specific topics such as “loop cutting,” “mirroring,” “smoothing,” etc..

Tell Us About Your Hammers (and Your Houses)

Have you been using other tools you’d like us to know about? Send us notes about your experiences (and screenshots and links to Thingiverse things) to support at makerbot dot com. And don’t forget to tag your Thingiverse objects with the software you used to create it to help people learn more about your design process.

1. You can perform this same experiment in Blender, but as the user interface is infamously difficult to parse at first, I tend to recommend Wings3D instead. For the brave, here are some great tips for solid modeling in Blender. [↩]
2. known knowns and known unknows [↩]