I went up this morning and almost immediately it felt like something was binding the track or like the track was ratcheting. I couldn't figure out what was wrong so I loaded it back up. I got home and decided to pull the secondary and found that all but two of the bolts holding the helix on had sheared off. Has anyone had this happen before? It looks like I can replace the bolts and be good, but I'm wondering if something else is going on to cause this.