My Z-rail bearing assemblies (the square tube with the bearings) are slipping relative the the part of the Z-cart that holds the Dremmel (z-sled). Maybe I'm missing something, but it seems to me the only thing holding them together is friction. I'm guessing that works fine if the sled+bearings are sandwiched tightly between the z-rail steel rods. The way I see to adjust it is varying the thickness of the washers on the bearing assembly.
What configuration of washers did people find to work?
At first I tried a washer on both sides of the bearing (between the bearing and the square tube and between the bearing and the bolt cap). That seemed like it sandwiched everything too tightly together to the point where it felt like it was putting some resistance on the z-cart's movement. But with no washers it's apparently too loose now.
On a different topic: when I jog the Z-cart in EMC, it moves in the opposite direction I would expect. The little "tool" shape in the program moves in the direction I would call "up" when my actual tool is moving down. Is there a convention for what direction is positive/negative on the Z axis and where the 0 point is?
Thanks,
Scott
