This page documents how to use Google SketchUp to create 3D models suitable for fabrication. These instructions should work on both the Windows and Mac OS X versions of SketchUp.
The design flow is roughly:
- Create a 3D solid in SketchUp.
- Export your model from SketchUp to an STL file, using the free DXF/STL Exporter plugin.
- Convert the STL file to a G-code file, using a tool such as Skeinforge.
- Run the G-code file on your fabricator.
What is Google SketchUp
Google SketchUp is a comparatively easy, free 3D modeling tool.
Using Google SketchUp
- First, download the free Google Sketchup tool. You don't need SketchUp Pro to create 3D models that you can fabricate — the free tool is good enough for almost everything you need to do.
- A tutorial in SketchUp is sadly outside of the bounds of this wiki page. However, Google provides an excellent series of tutorial videos. Even though SketchUp is easier to learn than most 3D CAD applications, these videos are the best way to summit the SketchUp learning curve, and can save you hours of frustration.
Use the DXF/STL Export plugin
The recommended method of exporting an STL file from SketchUp is to use the DXF/STL Export plug in, described below. This method seems to provide the best quality STL file with the least effort.
- First, download the DXF/STL Exporter plugin and install it.
- Fire up SketchUp! You should now see an "Export to DXF or STL" option in SketchUp's "Tools" menu.
- Now, load or create your 3D object. Be careful to ensure that you create a closed, gapless model (http://www.smustard.com/ has a variety of scripts that can help you validate or fix your model if you're having trouble).
- Select the object you wish to export, and select "Export to DXF or STL" from the Tools menu.
- The first pop-up asks what units you want to export your model in. I chose "millimeters," (though I'm still verifying that this works best for MakerBot).
- The second pop-up asks "Export to DXF," and you will want to select "stl."
- The final pop-up will prompt you for a filename for your new STL file.
- A few moments later, and you will have a shiny new STL file suitable for use with Skeinforge! Upload your new STL file to Thingiverse to get a quick preview render of how your STL file turned out.
Alternative 1: sketchUpBlender
There are alternatives to using CADspan's conversion tool. For example, the following page contains instructions for exporting from SketchUp to Blender, from where you can then take the Blender path to producing a g-code model.
Alternative 2: CADspan plugin
Initially, we tried to make use of the free CADspan plugin to export STL files, with mixed results. We found that the "DXF/STL Export" plugin described above was easier to use, did not require registration, and provided better results.
Using the CADspan plugin
- First download the free CADspan plugin and install it.
- After downloading the plugin, you will be asked to register to create an account on CADspan's website. Go ahead and do this: the CADspan plugin requires this account to function. When operating, it will upload your design to one of CADspan's servers, which will perform the conversion to an STL file for you.
- Once you are registered, load up your design in SketchUp. If you installed the CADspan plugin correctly, you will see an extra toolbar:
- To begin, click on the "Resurface" button in the CADspan toolbar:
- If this is your first time running the CADspan plugin, this should bring up a window asking you to log in. You've already registered, right? And validated your email address by clicking on the link that CADspan sent to you? Then go ahead and sign in.
- This should bring you to the resurfacer dialog box:
- All you need to do from here is:
- click the "Upload" button, and wait for your design to upload successfully.
- click the "Process" button to ask CADspan to start chewing on your design.
- Go make yourself a pot of tea. This could take a while.
- Come back, confirm that your status bar now reads "Complete," and click "Download" to download a zip file containing your STL file.
Alternative 3: su2stl.rb
- http://www.crai.archi.fr/RubyLibraryDepot/Ruby/em_fil_page.htm install the su2stl.rb file into the sketchup plugins folder.
- Click Script -> Export to stl and you are done.
- Note: the plugin requires an existing file to export to. just make a blank text file and name it what you want the final output to be.