We were inspired to create a linear bearing system the first time we held a piece of OpenBeam, those angled grooves seemed purpose made for wheels mounted to a carriage to track inside, or for slippy nylon pads to ride along. We tried lots of different ways to get a linear bearing to work, but found that low friction sliding plastic blocks lost their accuracy after hundreds of hours of use, and that flanged micro bearings tear up the aluminum OpenBeam rails, and that Delrin wheels slotted into channels on opposite sides of the rail were easily popped out off out of the channel if we put enough load either pressing down on or hanging from the carriage.
Over the years we have used high quality THK recirculating bearings on precision ground rails, and have found them to be exceptionally sturdy, while running smoothly and quietly.
After hundreds of design iterations we arrived at our own recirculating linear bearing design, which is at the heart of all the linear actuator systems that we sell.
<show wireframe cross section of bearing and OpenBeam here>
Reliability: We have tested our actuators up to 2.5 million full length strokes (with no load). Other than adding a small amount of Teflon grease every half a million cycles, we have not needed to perform any maintenance, and the bearings still hold tolerance like new.