| Software |
In order to get all of the ‘kinks’ out of your design you will probably find the following software useful.
– [$20] provides accurate translation of 3D geometry between the file formats used by many popular modeling programs. In the next part I will talk about how we can use these programs to get our file ready to upload. Beyond that .. they have mind-boggling capabilities that I haven’t even began to explore. |
| Create the STL file |
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First off – with a model that you are happy with you have to export from Google Sketchup.
File >> Export >> 3D Model The default Export type should be a COLLADA file (*.dae). You can use the default File name which will be the name of your Sketchup file with a .dae extension or put in something that makes you happy. Suggestion. The VERY first thing you should do before you go any further is set up a file system. Here’s an example: Suppose you create a 6-in Gate Valve. You might set up your files something like ..
The point is .. if you don’t set up a ‘system’ you will find yourself searching for that file you just KNOW is there .. somewhere. Now. Open MeshLab and .. File >> Import Mesh >> .. and browse to where you saved your .dae file you just exported from Sketchup. Leave the “Pre-Open Options” to Full Scene and click “OK”. The file will load (the larger it is the longer it takes – duh). Note. After the object loads to the screen you can move it around using the mouse. Middle mouse button lets you move up/down and left/right while the Left mouse button lets you rotate the object. For now you can ignore all the ‘cool stuff’ since we are only using the program to create a STL at this time .. So .. File >> Export Mesh As >> .. From the drop-down on the bottom select ‘STL File Format (*.stl) .. enter a File name or leave as is .. browse to where you want to put it and click ‘Save’. |
| Follow the Rules |
| There are several important things that need to be taken care of before you can upload the file. Shapeways has a tutorials on doing this including checking for Watertightness and Manifoldness – Things to keep in mind when designing for 3D printing |
| Is it Watertight? |
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Objects must be closed : Called ‘watertight’ by the 3D printing services. This is basically what it sounds like .. an opening in the surface of your 3D object. If you could ‘float’ your virtual object in a virtual bathtub .. these openings would allow water to enter and the object would sink. There ACTUALLY isn’t any water of course .. but it confuses the heck out of the 3D printer. These have to be fixed.
You can download a program – AccuTrans3D. Free for 30 days, it costs you $20 after that. AccuTrans3D can highlight the areas that are not watertight. To be completely honest .. I think my copy is still in the zip file from the download. I run it from there and the trial has never expired. You just need to load your STL file into AccuTrans 3D. Then .. Tools >> Check for Water-tight Meshes. That’s it. You will either get a OK .. or not. If not .. then we need to sort that out .. elsewhere. (there may be a way to do that here but I don’t know it) |
