Normal Mast Curvature or Bent Mast?

[brucybaby]

I was at my CreekFleet shakedown sail the other day and one on the guys commented that my mast had a bend I never noticed, but there a slight gradual forward curvature to the mast near the spreaders. No kink and no sideways bend to it and she seems to sail fine. I keep the mast in the crutch with the sail slot facing down. I was toying with the idea of turning it over and hanging some weight around the mast near the spreaders to slowly bring it back to a straighter profile.

Question 1: I've read today on the internet that some masts are designed to have some amount of forward curvature for weather helm???. Is this the case with a DSll?

Question 2: If I do need to try and straighten it, would this be a reasonable method? or will I be causing more problems? If that's so, I'll just sail it the way it is unless I hear of some other frugal repair method. Grandma doesn't need to be absolutely !00%, I just want to keep her functional for as long as possible

Any input will be appreciated, Thanks

[GreenLake]

How do you store your boat during the winter? Could this be from snow-loads?

Masts are actually not that easy to bend permanently, and correspondingly it takes significant force to bend them back - for significant bends there's also the risk of snapping the mast.

I don't believe the curve is by design, but do you need to do anything about it?

If you're "just sailing around" then it would be a question of whether you get an imbalance in the helm but you could correct that also by changing the mast rake...

I would be tempted to suggest that you might compare with another boat (sail together upwind with best trim). That should give you an idea whether you can observe any deleterious effect on pointing ability or helm balance - and how much. That should give you a better idea whether this is something that you want to address for that particular boat.

Rotating your mast for storage might potentially help, esp. if the mast holds up a tarp with significant snow loads for several months.

My mast has a slight sideways bend that I tried to correct but couldn't ... that's all the direct experience I have with this.

[K.C. Walker]

Fore/aft mast bend affects the mainsail draft. The luff of the mainsail is not cut in a straight line but with a convex. The amount of convex and the optimum amount of mast bend makes the most efficient sail. Each sailmaker puts a slightly different curve on things and recommends a certain amount of "prebend" for the baseline sail tune.

If you're mast curves aft at the spreaders you have what is known as negative prebend. Most sail makers would specify a positive prebend. The luff curve on my sail is 4 1/2 inches and the sailmaker recommends 1-1/2 inches of prebend. This happens automatically on my boat by stepping the mast and tensioning shrouds. The sweptback spreaders are designed to do this.

If the bend is really slight, check your mast when it's up and under tension. It might be that there's some positive prebend. If you have a one-piece mast that is keel stepped you can definitely put prebend in it by chocking base of the mast back.

[brucybaby]

Thanks GL and KC for all the good info

How do you store your boat during the winter? Could this be from snow-loads?

Thx GL. I don't know how this boat was stored the first 42 years, the last PO just tarped her and snow loads would happen if she was improperly braced. Like all ol' gals, i'm sure she's had her good years and bad. I'm going to go with the idea of rotating the mast. If she straightens up over time, all is good, if not, she still sails well enough to enjoy and her competitive years are behind her.

If the bend is really slight, check your mast when it's up and under tension

I'll have to check this out. It came to my attention after I had lowered the mast on my last sail. The mast does appear to be tipped back a bit at the base, maybe the problem is a non issue when raised. Thx KC