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Mast measurements

Started by Interested Party, 16 Aug 2012, 03:20

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Interested Party

All,
I am looking to replace my old gold proctor mast (with a diamond) with a later more flexible alloy Proctor C mast with spreaders.  The boat is Sparkle - a Starfish from 1967. 
At my club there is a stack of masts from various broken up boats, some of which have spreaders, etc, still fitted.
So a 10 mins with a tape measure will sort this avenue out once and for all.
So what is the mast length for a hog stepped mast and how far up should the spreaders be set?
I am not in a rush, but if there is something suitable right under my nose then I might as well get on with it
Steve Hawkins <br />N12 - Planet 672 -1948 (Holt modified 500 series)<br />N12 - Spider 2523 - 1971 (Spider) <br />N12 - Sparkle 2383 - 1967 (Starfish)

JohnMurrell

Steve,
 
Unfortunately not an easy answer...............
 
The Class rules allow a max of 6100mm from sheerline to the top band and I think its fair to say that most people try to achieve this to give max head room for both crew and to a lesser extent the helm. One thing to also remember is that the taller the rig, the more healing movement you get.
 
The key to getting the height right is finding the sheerline and then measure the distance from the hog to the sheerline. You then add that to your chosen rig height. In theory there should be a sheerline marked on your existing mast but given the age of the boat I suspect that you won't find one or if you do it might be incorrect.
 
If you go to the 'Owners Stuff' - top right of the webpage - and follow the links there to both class rules and more importantly the measurers guide you will find the way to measure a sheerline and the get the correct mast measurements.
 
And as to spreader height - I have seen so many variables on this measurement through the years but I have posted a Needlespar mast set up on the forum before, from memory look at N2760 on the database.
 
Good luck with the search