Sources of components for 3D models

When creating models, quite frequently, I use standard, nuts, bolts, extrusions, motors etc., even linear rails and other more complex, off the shelf parts. 3D models of many of these are often available from the manufacturers but it can be difficult to find or even to know which manufacturers provide 3D models that are suitable to include in my own designs.

The following are sources I use to look for pre-built 3D models of components:
https://www.3dcontentcentral.com - many suppliers include their models on this site. Available in numerous file formats.
https://www.mcmaster.com - this vendor has all sorts of fixing, nuts, bolts, threaded rod and many, many more. Their site is also included under the insert menu in Fusion 360.
https://grabcad.com/library - this tends to be individuals who upload their own designs.


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