Kerk Motion Product's 4000 Series ScrewRail combines drive,
support, and guidance, in a single, compact unit. The
arrangement eliminates external rail-to-screw alignment, an
expense item for typical two-rail systems. A proprietary coating
also eliminates external lubrication and can extend nut life by
more than a factor of three. CD/DVD duplicators from Amtren use
the ScrewRail product to lift and rotate an all-mechanical
pickarm.   ScrewRail actuators from Kerk Motion Products,
Hollis, N.J. (, help simplify design of automated CD/DVD
duplicators and halve costs compared with previous systems.  The
duplicators from Amtren Corp., Montgomery, Ala. (, use the
ScrewRail product to lift and rotate a special, all-mechanical
pickarm assembly. The pickarm lifts blank disks (by the center
hole) from a stack, rotates into position, and drops them into a
CD/DVD burner. It removes the copied disks then shuttles them to
an output stack. Some duplicator models also transfer copied
disks to a printer.  One key to making it