The following is a collection of thoughs and experiences on
cube lubrication. It only applies to the Ideal cubes which
are the only ones I have played with, but should have some
applicability to other brands.

Getting a smooth turning cube seems to me to be a combination
of the right lubrication with the spring/screw tension. If the
screws are too lose, the cube will turn easily, but frequently
jam since the lose cubies tend to get in each other's way. On
the other hand a very high tension without any lubrication would
mean a very stiff and fast wearing cube. My solution is simply to
use candle wax. I have taken my cube apart and rubbed each cubie
with a standard candle. (My friend from the Chemical Eng. Dept.
says parafine wax would be even better. This is what we used to
rub on our skis back in Norway before all the fancy ski-waxes
became available. I don't know how easy it is to get these days.)
I also "fine-tune" the cube by adjusting the screws on each face.
A couple of strips of double-sided tape stops the caps from acci-
dentally falling out during use. You may need to take the cube
apart a couple of times after the initial lubrication to allow
superfluous wax to fall out. I also found that turning a newly
waxed cube under a hot tap seems to make the wax settle nicely.
This lubrication has the advantage of not (seemingly) coming out
on your hands or otherwise disappear,- one treatment will last
you very long indeed. The only slight problem is that the cube
needs some "warming up" when it has been left idle for some time
especially in cold places. (Ref. my earlier message) But a couple
of minutes of random twisting produces a smooth and silent cube.
Good luck
OLE