My boat did not come with the lower lifelines. The 2nd lifeline I think is a necessity so here is how I went about modifying my existing stanchions. I purchased some stainless tubing from McMaster Carr and cut them 1/4" longer than the outside diameter of the stanchions. I also drilled holes in the stanchions to fit the new tubing sleeves. Remember to line up the new drilled holes with the existing top hole. The two stubby screws that you see were modified to resemble the flare angle portion of a flat head screw. I would have used flat head screws but didn't have the proper diameter so I modified the socket head cap screws.
(http://i153.photobucket.com/albums/s233/dtskibo/July2006010.jpg)
I simply inserted a screw into each end of the tube sleeve and clamped the assembly in a heavy duty vice. The clamping pressure of the vice along with the flare of the screws flared the sleeve and locked the tube sleeve into the stanchion.
(http://i153.photobucket.com/albums/s233/dtskibo/July2006017.jpg)
And here is what the finished product looks like. You must make sure your threaded straight end of your lifeline stud passes through the finished sleeve. Work with your lifeline rigger to assure his studs and your sleeves are compatable.
(http://i153.photobucket.com/albums/s233/dtskibo/July2006020.jpg)
The cost to modify all of the stanchions was under $20.
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