Spreader angles - B331

[Bluenose]

Hello all, I just read an excellent article in Good Old Boat Magazine that stressed the importance of spreader angles. That is, they should be pointing up.

I looked at mine on my Beneteau 331 and they were horizontal. This is my second year with the boat and the mast was up when I bought it, so I don't know how they are mechanically attached. I will be taking the mast down this year.

Does anyone have a comment on this?

Thanks,

Mike Casey

 

[jssailem]

Congrats Mike... 2 years and she is still afloat. It is like a Miracle... I am sorry... just a moment between coffee cups. Sounds like you are doing things correctly.

My spreaders are horizontal. The intent of the spreader is to spread the stresses evenly across the mast. Thus keeping the mast in column. I have not read the article in good old boat. From an engineering perspective if you change the angle of the spreader you change the way the forces are applied to the boat and it's gear.

In my way of thinking, Tips angled up would increase the tension on the upper mast, rigging, and connections. While this might increase the force of the mast to the keel, better placing the sail driving force on the keel, there is a balance to these forces and to the materials designed into the boat.

Spreader Tips angled down would be negative in all manners of consideration.

 

[Ted]

Spreader tips should angle upward slightly. The spreader angle should be set so that the angle between the spreader and the upper and lower portion of the shroud where they intersect are equal.

 

[Ted]

The reason your mast has spreaders is to increase the angle between the mast and the shroud. Imagine if a mast didn't have spreaders, the angle would be rather small. By adding spreaders, the angle increases. It's like moving the chainplate outboard by many feet which will more easily support your mast with less load on the standing rigging.

 

[Bluenose]

Thanks! I checked ZSpars' website (they manufacture the masts) and checked the replacement spreader kit. From what I can see on the site, they look strictly horizontal.

 

[DougM]

The Zspar spreaders are attached to a solid boomerang shaped extrusion that passes through the mast. That part when in position puts the spreader attachment perpendicular to the vertical mast. The hollow spreaders are slid onto the extrusion and through bolted. There really isn’t a way of changing the spreader angle “designed in” although its possible to slightly adjust the up/down location of the spreader tips on the shroud by loosening the J bolts and moving the spreader ends up or down and then re tightening. I cannot recall seeing a Beneteau with a spreader setup that was not horizontal.

 

[Bluenose]

Excellent, my mind is now at ease! Many thanks.
Mike Casey, Halifax, Nova Scotia, Canada