I've had some tough times getting the sidewinder x2 fully tuned. 

This helps so much with getting everything to run smoothly.

Instructions

Follow Ethereal Project 3D's instructions in this video. 
Squaring the gantry on the Sidewinder X1 3D printer, the EASY way.

I recommend replacing the couplers for the leadscrew and changing the leadscrew nuts out for POM anti backlash nuts while doing this. 

This is a re creation of his file from the video. His really didn't fit my sidewinder x2 but the concept is the same. I made it a bit smaller as well.