A major issue that comes up in making a MechAnimation is interference, meaning that one part gets in the way of another. Watch closely as you try to operate it, and you can usually see what’s getting in the way of what. Shown above is a common interference problem and its remedy:
**The ears of one paper fastener get hung up on another paper fastener. **A simple solution is to turn one of the paper fasteners around, so its ears are on the opposite side of the cardstock parts.