These shots are of the gin pole on Chris Park's Reynolds 21, which has a SC20 mast(33'), and a boom.
The gin pole has a yoke that pins to the the mast thru a hole located at the widest point of the mast. Just forward of that is a standard small boat trailer winch. Chris currently has wire on this one, but I used a 7/16" line for years. This runs fwd to a block just aft of the pole tip. A vertical slot, just slightly wider than the forestay diameter, is cut in the pole, which lands just above the nico press sleeve that secures the thimble that terminates the forestay. The winch line terminates in a cast hook with a spring loaded keeper, and this snaps to a s.s. ring at the junction of the 2 bridle wires. Also attached to the tip of the gin pole are 2 guy lines that clip to the ends of the main beam, stabilizing the pole in the centerline plane. This system requires that the mast be likewise secured side to side to keep it in that same plane. This boat came with baby stays, attached just below the spreaders, that could be quickly transferred from their fwd chainplates to the beam ends(which have stout s.s loops welded to the end caps). Trapeze wires could work too. Or install something that could be used for this purpose and secured out of the way under sail. So, with these secured, pin the yoke to the mast, slot the forestay, attach guy lines to beam ends, and clip the winch line to the bridle wires. With the side stays attached to their chainplates, engage the pawl on the winch and crank away. The mast crawls up with no drama, and the gin pole holds it up securely while the loosened forestay turnbuckle is pinned to the ring. Then the winch is released, gin pole removed and forestay turnbuckle tightened. With all lines properly attached, this is easy and safe. But always be vigilant, the forces are big, and the consequences of mistakes are significant. One advantage of this system(as opposed to one working off the trailer) is that the mast can be raised and lowered on the water, useful for bridges and negotiating ramps with overhead obstructions. For many years I kept the boat assembled full width on the trailer, and raised and lowered the mast each launch. Took about 10 minutes, up or down.
