Supported linear rail question.

[Ross77]

The load planes are in the same direction wether you mount the rail laying down or tip it on its end are they not ?

What do you mean by load "planes"? are you refering to the loads/forces placed on the bearing or resistive load capabilities of the bearing?

If the rail is mounted vertical then it is not technicaly subject to gravitational forces(because the bearing moves in this direction) so it only has to deal with cutting forces. X and y have to take the weight of the machine as well so loads are not the same in all planes.

As the bearings are open on one side then this area has reduced capacity by about 50% (so depending on the mounting orientation this will be different for each axis/plane) which is why I believe that they should be mounted back to back to even it out.

[Gary]

The rail is designed as a supported type, but you put it on its side and it is not supported as well anymore and you could bend the rail if the weight is too high.