I made and installed two 1 1/4" SS poles (one next to Nav desk and one in the galley. Both push up against the overhead, greatly stiffening the coach roof and provide a strong point to grab onto. Both poles are easily removable (for attaching eyes or fittings). Both poles are 316SS schedule 40 pipe.
Galley pole is adjustable with two 3/8" bolts (I welded the nuts to the upper part). Nav pole is adjustable with a 3/4" bolt that unscrews /screws into a nut that is welded to the bottom end of the pole.
Galley pole fits into a metal bracket that has a 1" schedule 40 pipe. this pipe as two tabs welded and those bolt to an epoxy block at is molded to fit the contour of the overhead in the formerly-inaccessible space in the fiberglass molded upper cabinet. The lower end is a bolted to fiberglass boards that are epoxied to the hull.
Nav pole fits into a custom molded, circular fitting that is epoxied to the overhead. The pipe fits into a recess that is divided by a 3/16" tongue of thickened epoxy molded into that fitting. The upper end of the pipe is slotted to fit this tongue. Purpose of tongue/slot is to prevent the pipe from rotating when I turn the lower bold (unscrew) to extend the length and push against the overhead. The lower bolt threads into a nut that is welded to two 3/4" washers, which are welded to the bottom end of the pipe, all sanded to near-mirror finish.
I made a stainless steel lower bracket with a center recess, where the bolt head fits (and can rotate). This recess is a close fit to the widest diameter of the bolt head. This allows the bolt to turn during install/uninstall, but very little room for it to slide around.
Later, I will finish the upper end with a piece of wood the I will turn on the lathe to form a cup-like medallion that will cover the upper epoxy bracket and its collar. All one will see if a pipe coming out of the cabin sole and entering a wood trim on the overhead.
It took months of contemplation to figure out how to create two poles that are easily adjustable, clean looking, secure (so when I smash against them, the won't move), easy to install and remove (I know I will weld additional features to it in the future), and not astronomically priced, The pipe was the most expensive (about $200 for the three pieces (8' for nav, 4' for galley plus a 2' piece (only used about 8") for the upper bracket of the galley pole.
This is one of the few projects that actually executed without any major mistakes or wasted attempts (wish I could say that about all of them).
More pictures:
Galley Pole: http://bodylens.com/Gallery/thumbnails.php?album=43
Nav Pole: http://bodylens.com/Gallery/thumbnails.php?album=44