thk blocks and rail question

[funkenpedro]

I have a couple of belt driven linear actuators they use thk ssr20 bearing blocks and rail,

When I got them the moving stages of the actuator were connected to 3 bearing blocks riding on a single rail. I wanted to reconfigure them for my setup and I took the middle bearing block off the stage to use it on a support rail at the other end of the axis.

When I tried to put the stage and 2 remaining bearing blocks back on the rail there was slight difficulty as if by removing the middle block from the stage allowed the metal stage to warp slightly. ( I did not loosen the remaining blocks). The stage at this point made more noise while rolling on the rail.

If I loosen the two blocks from the stage the stage moves quietly, but when I torque it on to the blocks even slightly the rolling sounds much louder.

There is no significant increase in rolling resistance either way.

Is there a method to torque the bearings down properly?

Should I bother pursuing this issue?

thanks
pedro

[Glacern]

A stage that is fairly rigid but not flat will cause the blocks to bind. The center block was probably flattening out the stage enough to reduce most of the binding on the outer blocks.

Your solutions are to either reinstall the middle block (I'd recommend this), machine the stage flat on a mill, or live with the binding.