Step 16: X-Axis Lead Screw
The y-screw has been installed. The x-screw is now needed. Assembly and concept for the x-screw is the same as the y-screw. The only difference is that you will need to pick up the entire machine and provide access to the bottom.
Just like the other axes, alignment is critical. It doesnt have to be perfect, but pretty close. The coupler that I use allows a tiny bit of flex since the middle component in the coupler is rubber.
Placement of the nut doesn't have to be set within one of the support pieces (i.e. y-axis nut in the y-axis bearing support). I personally like the simplicity. If the hole is too small, the nut can split or crack the MDF. Alternatively, the y-axis screw can be positioned just above the y-axis lower bearing support. The x-axis can also be positioned just below the bottom gantry support. With the measurements I used, the z-axis is not as flexible; however, if the y-axis bearing supports are a little longer, the z-axis nut can be offset. These alternative locations will enable the positioning of a homemade anti-backlash nut.