I've recently started a model project (souping up a Visible V8!) and
one of the first things that came up is... with what do you lubricate
it? Ask a chemist "what lubricants attack polystyrene?" and the
answer is something close to "Oh, wow, just about everything."
The Visible V8 manual advises using vegetable oil, which is a great
choice only if you want to sell a brand new model every six
weeks. Polystyrene slowly dissolves in virtually all natural oils, and
vegetable oil also polymerizes into a solid gunk in the presence of
oxygen.
The Internet is full of completely ludicrous advice on the subject of
lubricants and styrene. And, of course, vendors don't want to tell
you what's in their products or what their criteria is for declaring a
particular lubricant 'compatible' with a given polymer. MSDSs are
useful for establishing that several lube vendors are probably, to put
it bluntly, lying through their teeth about compatibility.
So, what to do? We test.
( More under the cut )