Jib Boom Experiment

When I'm out by myself I like to use the Working Jib because I have it rigged as an Auto Tacking Jib.
The problem with using the Auto Tacking Setup is I cannot get quite the shape that I would like out of the Jib.
After a little head scratching I thought a Jib Boom might be the answer.  I looked at some commercially available Jib Booms and they are expensive.
So, once again, I found myself roaming the isles of the hardware stores in search of inspiration.
After a few weeks of ruminating I began cobbling together a proto-type.  It was crude but the experiment did point out some areas that I had not concidered before this project began.
The problem I encountered was that I could not lower the Jib with it attached to the Jib Boom.  The illustration at left explains the problem.

We mark a point, A, on the Jib such that a line drawn from Point A to the Clue will be perpendicular to the Forestay.  We will next mark the Clue as Point B.

As we lower the Jib point A progresses down the Forestay but as you can see point B, which is attached to the end of the Jib Boom, cannot move.

Each Red Line, AB is the same length. The progression of the red line illustrates the fundimental problem with my proto-type.

As the Jib is lowered the distance from A to B is fixed and so with the Jib Boom attached to B you can see the Jib will get stuck from the top red line down or tear loose from the Boom.  (Continued Below)



I began working on this problem during October of 2009 and was frustrated by the coming end of the boating season because the Christopher-Jin had to be put up for the winter.

I did come up with a possible solution that just might make my inexpensive Jib Boom a possibility.

If a line (shown in Blue) is tagged onto the Jib Halyard and run as shown in the illustration to the left, then as the Jib is lowered the blue line will pay out making up for the shortfall of the Red Line AB.  Notice the dotted blue lines.
 (Continued Below)
The third illustration (Below) shows the basic Jib Boom Proto-Type.
 More coming this Spring.
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