For crossed roller bearings on linear sliderails, the rails’ lengths determine the length of the stroke or travel. The entire rail assembly must be twice as long as the stroke. That’s because both rails containing crossed roller bearings move in opposite directions. That means the whole assembly has to have room to move inside a space twice as long as the travel length. (Recirculating-ball bushings used for linear motion need shafts only as long as the required travel because the only moving component is the bushing.)
When the bearing uses plastic cages, stroke length can be longer on a given length of rail because the cage can be shorter for a given load.
So one limit on a crossed roller bearing’s travel is the space available in the application. As mentioned, with the rails moving in opposition to each other, the overall space required is twice the distance the load will travel. Endstops are components mounted on linear rails that physically limit travel length, stopping the rails from going farther.
