MakerBot/How To: Find Or Create A Printable STL File

Downloading an STL file from www.thingiverse.com

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1. Load Google Chrome or Mozilla Firefox.
2. Go to www.thingiverse.com
3. Search something to print using the search bar in the upper right-hand corner.
 
Searching an object on Thingiverse
4. In the search results list, click on the link that pertains to the object you wish to print. Do not click on a link that is the image of something.
5. On the object’s page, confirm this is what you want to print by referring to the images on the left.
6. Near the bottom of the page find an STL file to download. NOTE: There may not be any file to download if the STL file for that object has not yet been developed.
7. Click the red download arrow adjacent to the STL file you want to print.
 
Downloading the STL file from Thingiverse
8. Refer back to the desktop to confirm the file was downloaded.
9. If the STL file is present, you have successfully downloaded the file, and are ready to print.

Have to create an account, can make a preference that want STL files ... then just download ... has all sorts of electrical and mechanical parts.

Downloading an STL file from http://www.3dvia.com

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1. Open Google Chrome or Mozilla Fire Fox.
2. Go to http://www.3dvia.com
3. Create an account.
4. In the upper right hand corner search for some thing in the search toolbox.
5. In the search results list, click on the link that you like the most.
6. Below the image a link to download will appear.
7. Download the STL file. NOTE: There may not be any file to download if the STL file for that object has not yet been developed.
8. Refer back to the desktop to confirm the file was downloaded.
9. If the STL file is present, you have successfully downloaded the file, and are ready to print.

Have to convert from sketchup file format to STL. Some items convert, others don't. Is a difference between mesh (STL) and frame file formats.

MeshLab is oriented to the management and processing of unstructured large meshes and provides a set of tools for editing, cleaning, healing, inspecting, rendering and converting these kinds of meshes (STL files).