The old DesignSpark Mechanical forum where I posted quiet a few "Tips and Tricks" has completely disappeared.
It seems that this company doesn't care of their customers and have no respect to the people that contributed there, which is a BIG SHAME !
Because of such an inacceptable attitude, I won't write anymore tutorials about DS Mechanical and invite you to use other softwares.
I will let you know which other alternatives you have.

Allied Electronics and RS Components have just made a new design software free for everyone : DesignSpark Mechanical.

DesignSpark Mechanical, as its name states, is a mechanical CAD system based on a professional-level design package called SpaceClaim and is well suited to producing parts for 3D printing with its ability to export in STL format.

With its ability to import native SketchUp files (.skp) it's also the perfect companion for SketchUp and those who love the SketchUp modeling ease-of-use won't be disappointed !
Adding filets, chamfers and doing boolean operations are the most interesting features I have tested so far along with driving-dimensions and the ability to export your design as 3D PDF.

I haven't played a lot with it yet but I've been completely seduced how easy it is to perform some operations like rounding corners compared to the very good Fredo6 "Round Corner" plugin in SU.
With just 4 major tools

  • Pull
  • Move
  • Fill
  • Combine

one can do incredibly powerful modifications to his design in DesignSpark Mechanical and then export it back to SketchUp if needed.

We, SketchUp users, are lucky because I've tried to import other formats (STL and OBJ) but they just import as meshes (with no hierarchy - OBJ looses all groups) while a SketchUp model imports as a solid (if it's a closed manifold geometry) or as surfaces (if it's an open geometry) on which all kind of operations can be performed.

That's why it makes it the perfect companion to SketchUp.
Try it out and I bet you will probably include it in your workflow !