Hobbies And Interests
Level Wind Systems
All level wind systems distribute line evenly, but not all systems necessarily have to have a screw to distribute the line evenly over a drum. Most systems have some kind of carriage that guides the line across a drum, then mechanically changes direction and repeats. A screw is one of the mechanisms or a portion of a system that accomplishes this task.
Screws
A level wind screw is a horizontal cylinder with grooves in it. The grooves are similar to the slots of a threaded screw, but they spiral in two directions. The pattern looks like argyle wrapped around the screw. The grooves move a carriage in a track horizontally, then guide it back. The same mechanism can be seen in old, automated screwdrivers, which you push down so cylinder grooves cause the screwdriver head to spin -- however, this is a different application of a very similar device.
Switching Mechanism
Level wind systems must have a system to switch directions. Think of it like a typewriter return, but instead of starting over, it just sends the carriage back the other direction. Sometimes the system is designed, in part, into the level wind screw; sometimes this function isn't facilitated or assisted by the screw. That means level wind screws are designed specifically to work within a level wind system.
Ratio
Many level wind systems employ a variable ratio of drum revolutions to carriage movement. For example, if a system is winding a half-inch braided steel cable, some systems align the windings perfectly adjacent to one another, so each full revolution is horizontally offset by precisely half an inch. These systems may use gears or other mechanical systems to gauge the offset; some may even use computer software and sensors. Other level wind systems have a fixed ratio, which doesn't line up the windings perfectly but distributes them about evenly.