Making parts fit together more loosely. Printing STL files that arent editable in CAD

Hello. I am printing this mechanism:
http://thingiverse-production-new.s3...w_featured.jpg
http://www.thingiverse.com/thing:23030
I would like parts to be printed
so they are not as tight to each other so gears can go on the axles with ease and everything spins rather freely.

I printed this mechanism 2 years before and my printer got older, something changed and my parts print differently.

I would like to (thinking virtually) take the surface of every part and set it in by maybe 0.60mm to make parts smaller in all directions, but not to downscale them.
I don't know what official engineering term is.
I would also like ot know how to make this printer print less thick to make outer faces of the part more set in.
Just as if I made those gears out of ice and dipped them in hot water for a second. Some amount of material off the surface would melt off. I want to do this on the printer settings level or software level.

Thank you.

I used to print on Kapton film. Now I print a little differently.

Attachment 9302

I would like to know:
When I use scale and I make a gear smaller, I also make the hole smaller.
Is there any script that would set in all the surfaces by a given distance so when I make a gear smaller, the hole gets bigger?

So if I have a wheel with a hole in the center and I set in all surfaces by 0.05mm, then the wheel diameter will decrease by 0.10mm, the diameter of the hole in the center will increase by 0.10mm and the width of the wheel will decrease by 0.10mm as well.

Almost as if the part was made out of ice and an even thickness melted off of it from all directions.

Is there a script that can do that?
How hard would it be to write one?

What terminology should I use to describe this operation?

Thank you.

--Vladimir Tolskiy

If you edit the OpenSCAD source files, you can change everything just the way you want. Take some time to learn OpenSCAD and you will profit from that skill for the rest of your life. I did and I now exclusively design all my parts in OpenSCAD, leaving Autocad/bricscad to gather dust...