spearder on a mast

does any body know were the spearder goes on a mast it is 42 foot long and it is a 1986 hunter 31 footer and how long does the speader half to be to work right and what angle do i put them at up down or back on the mast:?: :?: :?: :?:

 

Just in idle curiosity I am interested in that too, and are they necessary on say cats without a main? (Thanks sailboatman for the "hijack" but maybe there is strength together in our quests....)

 

The simple answer, sailboatman, is that the spreader goes where the boat's original designer drew the spreader.

Rig engineering can be a tricky art (I don't do it myself, not yet at least). Essentially, what a spreader does is to reduce the free length of the mast tube. By constraining the mast at a few points along its length, we can get by with a lighter, thinner mast that would probably buckle without this extra support. Spreaders are generally designed to be in pure compression- they bisect the angle they make in the shroud, and lie in the plane defined by mast step, mast head and chainplate. Or at least, they are supposed to come close....

To actually design one is a little more complicated, and for that I would refer you to someone more qualified than myself.

 

Yep, Matt nailed it on the head. Hunter Marine can provide you the details for your rig. It may be possible to get this information from one of the mast manufactures, though you'll have to pay them for it as will.