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How to export cad file format skp (sketchUp) into solidworks
You might try this...
99 cents per translation
http://www.babel3d.com/Home/Translateor try this two step process...
Free SketchUp plugin to export dxf or stl
http://www.guitar-list.com/download-software/convert-sketchup-skp-files-dxf-or-stlthen use this...
Free Convert stl to step
http://www.solveering.com/products/products_stl2step.html
No need for any extra programs or plug ins if you have sketch up pro, kick it out as a DWG and when you import it to SW just make sure to switch it over as a 3D model that you want to import....