Linear Rail 12mm Carriage Block MGN12H
Make your robot or CNC move on our 12mm Supported Slide Rail with this sliding ball-bearing platform. The slider has four holes tapped for M4 machine screws so you can attach pretty much anything you want. This slider has a plastic interior with circulating ball bearings to make it slide smoothly along the railing.
The platform won't come off the railing once attached. It's also relatively well supported due to the T-shaped rail, so for ~5 lb loads, you can probably get away with just one rail. Often, CNC projects will have two of these on opposite sides of the machine body to support a larger platform. You can also have some other support mechanism of your devising.
It comes as a single bearing platform. You'll want to pick up at least one 12mm railing as well.
Do not try to attach onto the railing without the plastic insert! The insert keeps the ball bearings in while you fit the slider. See the photos for more details on how to do this! If you lose a ball bearing or two, it'll still work, but its best to keep them all in!