spreaders

[seandwyer]

Hi Folks,

Two of my spreaders have cracked - probably due to age and stress. I replaced the short one with a piece of aluminum stock tubing I bought from home depot and felt pretty good about that. But last week one of the long ones broke right where the large pin fastens it to the mast. I think in general the material isn't thick enough in that area because so much has been removed for the hole the pin goes through - but I guess I'm stuck with that configuration. My question is this: I have cut another section (21-1/4") to match the length of the other one and am about to install it tomorrow then sail on Sunday. The diameter of the tubing is the same as the previous spreaders, but the wall thickness of the new one is actually thicker. This has made me feel good about it until last night when it occurred to me that perhaps the spreaders, albeit aluminum, could possibly be made from an alloy, and my new hand made ones might not be up to snuff. Does anyone know if I am asking for trouble here? What should a spreader be made of? I wanted to use stainless, but couldn't find any hollow stock to use.

Thanks for any advice!!

[Phill]

Hello,

My stock mast came with spreaders like you describe. The longer lower ones are all you really need. If you have a second set of shorter upper spreaders and shrouds, You can do a search here and find discussions about removing them.

I raced with the original 1/2" tube, 21-22" long, spreaders for many years with out trouble. I am wondering why yours are breaking. My spreader brackets were only small cast 'ears' large enough for only one 3/16" hole for a cleavis pin to hold each of them to the mast. If properly set up they should always be in compression, with no sideways or outward pressures to break them. When your rig, (mast-shrouds-forestay-spreaders) is tensioned for sailing, the spreaders should be angled a few degrees upward from horizontal. The angles that the shrouds make at the spreader tip, above and below, should be the same. I have used whipping twine to make a little ball on my shrouds that makes a 'stop' so that the spreader will not slip below that point. I have seem many who do not to this and thier spreader tips droop to the point that there must be a lot of unnecessary pressure on the spreader at the bracket that might make it break.

Because I wanted to experiment with spreader length, I replaced the original 1/2" diameter Aluminum tubes with 5/8" (all i could find at the time) that were not a special alloy. They worked fine for many years.

Hope this helps.....

[seandwyer]

Hey Phill,

Yes, it helps. As long as the material is not a special grade of alloy I feel good about it. To show how mine are fastened to the mast, I might need to snap a couple of pictures. My spreaders can't move when the mast is in place, but when it is down and the stays have slack, the spreaders just droop. I think that the long one must have gotten caught in a less than perfect angle a few times as tension was applied as the mast went up. This caused a stress fracture and then, eventual breaking off entirely. I am interested in understanding more about what whip cord is and how it could be tied to the shroud and not just be pushed down or up as the spreader applies pressure. How does that work? Is it a special knot?

As for the small spreader - it was broken when I bought the boat - when I removed the tarp it was broken - perhaps from the pressure the tarp was applying or snow load or who knows what. Everything is old, original and to some degree expected to break and need to be replaced.

Speaking of which - tomorrow I'd like to replace all the screws holding the step to the mast and it's mating surface that is held to the mast stub. Can anyone recommend the size and material I should buy when looking for screws? Everything is really rusty and looks like it could go at any moment. I also have a rivet that needs to be replaced on one of the spreader brackets - and not this week, but eventually, I need to replace the rigging. I have the smaller gauge original stays etc.

[GreenLake]

You can use rigging tape where the spreader meets the stay. That has two effects. For one, it protects your sail, if it comes in contact with the stay at that point, for the other, it might well stop the "drooping" and then you don't break your spreaders while you are applying tension.

Rigging tape is the stuff that sticks to itself, after you stretched it by twice its length first. It holds up well when exposed to the weather, but you can use other tape, of course.

[seandwyer]

Thanks GreenLake. Any suggestion on the screws? I guess stainless and cover them with some caulk or something so they don't contact he mast?

Thanks!

[GreenLake]

That would be my guess as well, but I have no mast-stub. Bedded SS fittings are usually fine in aluminum. TefGel if you can get hold of it, is said to be the gold standard for that purpose, but anything that isolates and allows the screws to be removed again would do.

(What you don't ever want to do is use screws that are less noble than the material they go into, that really focuses corrosion on the fastener - for those who are following this and would like to read up, get "The Boatowners Guide to Corrosion", great book).