This article was originally published August 2001 on SailNet.
Sailors often travel in full circles, and such has been the case with boom reefing and furling. In the 1940s and '50s, Eric Hiscock and others touted the advantages of mechanical roller reefing. These early units often consisted of a crank driving a worm gear assembly that rotated the boom. While they worked, the original boom roller-reefing gears left much to be desired.
The first obstacle was that fittings could only be attached at the boom ends, eliminating the use of boom vangs, mid-point mainsheets, and other desirable hardware. If you've been sailing long enough, you may remember special "boom claws," metal rings with rollers, that could ride on the reefed sailcloth with only minimal damage.
There were other problems with the old roller-reefing systems. The sail had to be battenless, or have the battens installed parallel to the foot of the sail, which reduced sail area. Sail track gates usually had to be custom-built to let the slides off the track as the sail was rolled down. The boom had to be round, which is not a good shape for strength, and these booms usually ended up far heavier than would have been necessary otherwise—a curse in light airs.