3D printing: check and repair your STL files!!
http://www.meccanismocomplesso.org/en/check-stl-files-3d-prining/
Got caught in the spam filter, but there’s some good info here so I pushed it on through.
Thanks! I appreciate it. I hope this info will be useful.
I liked the info on the page itself, but I am not yet liking the Will It 3D Print website that it suggests using. I used a known good model that I have printed and after clicking on the print button it took quite awhile to finish calculations and my part remained Blue - not one of the 3 outcomes that are expected, Green good - Red bad - Grey unknown - but what about blue? I feel sad )-;
Strange…blue means uncalculated. After that you upload the stl file and set the 3D printer model, have you pressed the button “PrintIt” ?
If yes, maybe there is some problem with WebGL version on you browser or something else. Does the calculation of roughness work?
Or if it’s possible, have you shared the STL file? So I can download it and try it on my PC.
And if you have some better way to work with STL file and you know some application better than those i suggested, you are welcome! 
You can open a thread in Meccanismo complesso’s forum, suggest new procedures, or write an article about that. We will be very happy of that!
The part is from a tinkercad design I created. It has printed twice from I.matrrialize and once from a Replicator 2. The same file should be available an my shapeways account under the name of modern chariot. It should also be on thingiverse under chariot.
Oh,sorry. I have only just received my own first 3D printer kit. I am still building it. So I don’t yet have any specific workflow going, just several designs related to the parts and pieces of the chariot.
OK. That’s is the first “fun part” for a DIYer!! After you’ve done it, if you wish to share your experience we can publish a post in which you describe the model kit, and how to assemble them. Take a lot of pictures! 