One of the common preconceptions about reprap-style printers is that they are a nightmare to setup. With AW3D, we have attempted to change all that. Follow these simple instructions, and in 5 minutes you will be set. As long as you don’t move the machine around too much, these settings should remain and the bed should not need to be re-leveled. We regularly transport our printers and rarely have to re-calibrate them.
First, run the circle calibration file. If your bed is not leveled, you will notice that the circle has high and low points and that some parts of the circle stick to the glass and some do not (make sure you are printing on PET or Kapton-coated glass misted with a mixture of ABS and acetone).
If the left side of the circle is low and the right side is high, or vice versa, the left/right adjustment will be your first adjustment. For this adjustment, hold one of the flexible Z couplers and turn the other (they tend to rotate together because of the magnetic connection). Turning a coupler clockwise, will raise the hot end, while turning the coupler counterclockwise, will lower the hot end. Once you have made the adjustment, run the circle calibration again to see the results. Repeat until the left and right side print heights are the same (within reason).
Once the left/right adjustment is completed, you should adjust the finer adjustments located directly on the bed. As background, the PCB bed is connected to an upper rectangular aluminum frame which is connected to a lower aluminum supporting frame (that holds the lm8uu bearings and supports movement on the y axis). The upper frame is coupled to the lower frame with three bolts (for leveling, a fourth bolt would be redundant and only drive you crazy). The rearmost bolt is fixed (or “pinned”), so the only adjustments are the two spring-loaded bolts at the front left and right of the upper frame. Because the bolts are fixed at their bases, the only adjustment needed is to the top nut on either. By turning the but in (1/4 turn at a time), you will notice that the plate lowers on that corner and raises on the opposing diagonal corner. Adjust the nuts and reprint as necessary until getting an optimum circle. Remember, to adjust overall height, adjust the allen bolts on the left X bracket.