Mast Bend in 84 Hunter 31

[Canadaler]

I drove to look at one of these boats yesterday. Everything looked very good IMO...until just before I was ready to leave I looked up to the top of the mast to check out the wind guage and was surprised at how much bend was in the mast.

I know the Hunters have some pre-bend built into the mast, but my understanding is that is done over the length of the mast, a lot of this bend appears to be above the top set of spreaders.

Just a wild guess...(I didn't think of measuring it with the halyard until I was part way home) but I think it was at least 6-7 inches. It was certainly looked bent more at least the thickness of the mast. I read that the standard is 1% pre-bend over the length of the mast...which should calculate out to something like 4" of bend.

Here's a couple of pictures, but it's not all that easy to determine how much deflection there is from them.





This boat has been raced weekly and does have a backstay adjuster added to it (non-stock.) I'm a little worried that might have been cranked down too tight on a regular basis and distorted the mast.

What do you think?

[Faster]

Not to worry.... it's very unlikely that the backstay may have permanently deformed the mast.

These B&R rigs get a good deal of their stiffness from the swept spreaders,"X" shrouds and a fair bit of prebend. As a result any tensioning of the backstays of these masthead versions pretty much all goes into headstay tension.

Your pictures are not at the optimum angles, but it does look like the bend is not uniform over the section, and could use some tuning.

[sailingfool]

Mast looks fine to me. I've never heard of a mast suffering damage from tensioning, unless obviously kinked, something else gives before the mast does. So the mast is fine, do you know for sure the backstay tensioner was fully off?

If the owner uses too much backstay or other rig tension, he distorts the chainplates (topside dimples) or the hull (doors dont close or hatch slide binds, etc..) or breaks something.

[Canadaler]

Thanks for the input guys.

Yes, I checked and made sure there was no tension at all on the backstay adjuster when I took these pictures.

This rig doesn't have the typical chain plate arrangement at a bulkhead. The spreaders connect to a rod which runs down and attaches to a stiffner on the hull below the water line. I checked that and everything looked good. Didn't see any distortions or anything that looked out of sorts.