Curved spreader

PabloPicasso

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image.jpegFractional rig, single spreader boat. I noticed this weekend that the starboard spreader curves down a bit. That is the shroud end is lower than the mast end, on the starboard side only. It looked more obvious when standing on the quay than it does in the photo .

Before I consider corrective action is there any cause I may be missing?

My plan is to loosen the shroud clamp in the spreader end, ease rig tension and try to straighten the spreader with a halyard before re-tightening the clamp, and tensioning the rig.

Is this folly to try and do same with the mast up?
Is the problem indicative of some other imminent failure? Sighting up the mast it looks straight as is. Am I worrying unnecessarily?
 
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Sorry but i'm not clear on what the problem is. On the photo it's difficult to make out the bend.
Is the starboard spreader bent along it's length causing the end to be lower at the shroud end, or is it straight and just mis-aligned with the port spreader?
 
I can't be sure, but that's not a discontinuous rig is it? If not, did someone stand on it? Or was that pulley hanging from it perhaps overloaded? And I'm assuming it was just not simply fitted off perpendicular?

If discontinuous rigging it might be poss to adjust out. If not, I'd prob replace the spreader as micro cracks can appear when trying to bend back, which in turn introduces a latent weakness. Also have a good look at the spreader roots - if any cracking is found it might be worth considering doubler-plates.

Might be worth asking a rigger but prob not worth spending money as they will want to cover their own backs.
 
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Spreaders should normally bisect the angle of the shroud, which means they are angled up slightly to give the same angle to the shroud above and below.

A bent spreader should be replaced as a matter of urgency but, if it's just drooping a bit, slackening the shroud and giving the outboard end a shove is worth a try, otherwise it's an up the mast or down with the mast job. If you go up, use the main halyard and another line to steady the mast as you'll need the shrouds to be slack.

I wouldn't sail until it's fixed - you really don't want it to slip any further down!
 
That looks like typical spreader droop where the spreaders have not been set to bisect the shroud angle before the shroud was set up. Slacken the shroud, push the spreader up and then tension. There is usually play in the spreader socket on the mast. On my boat there was too much play so we always use a bulldog grip to keep the spreader at the correct angle, then nice little leather boots to cover the end.
 
That looks like typical spreader droop where the spreaders have not been set to bisect the shroud angle before the shroud was set up. Slacken the shroud, push the spreader up and then tension. There is usually play in the spreader socket on the mast. On my boat there was too much play so we always use a bulldog grip to keep the spreader at the correct angle, then nice little leather boots to cover the end.

Yes, it's just drooping a bit. I'll try what you say.

I'll have a good look for any other problems as well while I'm at it
 
Yes, it's just drooping a bit. I'll try what you say.

I'll have a good look for any other problems as well while I'm at it

This is my solution to spreader droop Not up-swept as much as the photo suggests though!)


54kdt.jpg
 
This is my solution to spreader droop Not up-swept as much as the photo suggests though!)


54kdt.jpg

That's clever! Selden also do an adjustable spreader root though prob expensive and only for their spreaders.

Only caveat is that the spreader must not be curved when unloaded. In addition, the spreader angle must be correctly set in order to eliminate vertical forces under compression; which is of course bisecting the angle for a single spreader continuous setup.

I'd personally also have a good look at the roots; it's not as if spreader droop has not led to rig failure through spreader, root, and mast damage.
 
Well all done now. No visible damage.
Loosened rig, loosened clamp, repositioned spreader, and retightened.
A straightforward job with a helpful crew member lending a hand

Thanks all
 
Just to reiterate what has been said. Spreaders on a fractional rig are critical. The spreader base which dictates the seep aft must be robust and rigid. Angle to the shrouds is less critical but important. I lost the first mast on my little boat when the spreader base which was pop riveted to the mast peeled off due to rivet failure. This allowed the spreader end to move forward losing push forward of the middle of the mast which then crumpled backwards. Now I have a much more robsut spreader base and spreaders. olewill
 
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