Nut and bolt axle system
Layer Infinity return tops are held together using hex nuts and bolts. On each half, there are 6 possible ways a nut or bolt can be insert into the half. Combining the nut's half and the bolt's half, there are 36 possible ways the axle system can be oriented. In fact, you can also switch the nut and the bolt around into their opposite halves for another 36 possible orientations, resulting in 72 possible orientations.
3D printed return tops are very sensitive to the axle system's orientation, much more so than any other types of plastic return tops that also use nuts and bolts. Rotating either the nut or the bolt by one step can introduce a significant amount of vibration. "Tuning" means trying all possible orientations to find one produces the minimal amount of vibration. This is already done for you before shipping.
If for any reason your return top is not smooth (e.g. after a hard impact), then you can take the nut and/or the bolt out, rotate it to another orientation and repeat the tuning process.
When unscrewing your return top, be careful not to push the nut or bolt out. If you need to remove them, try using a marker or some tape to mark their orientation so they can be assembled again with the original smoothness. Otherwise you may need to repeat the tuning process.
Bearing (dis)assembly
Unlike many other return tops, Layer Infinity return tops' bearing posts are not part of the halves. The bearing is held in place by a "sleeve" on the axle which is separate from the halves. This sleeve is not threaded onto the axle. It may wrap around the axle tightly, but it may slide up and down. The pre-tuning process guarantees that the sleeve can produce a smooth result.
The bearing cannot be removed using a traditional bearing remover. To remove the bearing, use pliers to gently wiggle the bearing out.
- If the bearing comes out of the sleeve and the sleeve is stuck in the axle, "unscrew" the sleeve from the axle.
- If the bearing and the sleeve come out together, use a bearing remover to push the sleeve out of the bearing.