Was trying to create a simple box out of some 2x4. 1st attempt made it through the first half of the box, part way through the second did a sudden plunge when moving down. Researched the forums, tightened the z axis belt. Second attempt did the same thing on the first half of the box. Tightened a little more, had the same problem on the 3rd attempt. Attached is a pic of 2 and 3. It was cutting like a champ until it decided to go crazy on me. Any other thoughts? Thanks.