Our boat is an IOR era masthead rigged racer cruiser. The spinnaker pole is a a bit of a handful for my wife to handle, and the monstrous symetric spinnaker is even more of a handful short handed. So the decision was made to splurge and buy an asymetric spinnaker. I hated the idea of flying the new sail off the stem. so I looked into buying a bowsprit kit. Damn those things were expensive, and they aren't the most elegant solution. So I pondered for a while, and came up for a design for my own sprit. I made up a couple of drawings, went to the Metal Supermarket for some materials and took it to a welding shop to get it fabricated.
Well, here is what I have come up with. It is made out of Schedule 40 3" aluminum tube. The end of the pole is 3/8" thick aluminum to give enough meat to thread in a 3/8" ss bolt as the fastening point for the block. The reason I did that was twofold; I wanted to keep the outside surfaces of the pole free of hardware so that the pole is easily removable, and I wanted all of the load to swivel on the centre axis of the pole to eliminate any torque that might stress the inboard anchoring point. The forward collar is welded out of stainless steel tube, with a 1/4" thick tang that fastens to the same 1/2" clevis pin that secures the forestay to the stem. The inboard end is secured to a heavy stainless car, (originally a staysail tack point) using a 5/16" quick pin through two 1/4" aluminum tabs. The car slides on a pre existing track. the pole can be extended and locked in place in seconds. Because of the slope of the deck where the track is mounted, the pole lifts up when retracted giving plenty of clearance to use the bow cleat that is under the pole.
Ok, confession time! This project did cost more than $100 but even at $200 it saved me hundreds of dollars, and I didn't have to drill a single hole in my deck!
(oh yeah, and the brand new Quantum chute definitely cost more than $100!)