Forestay Cotter Pin Maintenance

[Pauls]

Suijin - No. The length of the pin has nothing to do with the sideways force which is bending the cotter. If you will read my response you will note that I said that if the pin is a significantly loose fit in its masthead hole then adding a washer with an ID a close fit on the pin OD will improve the situation. Pin length is immaterial. The radial distance between where the cotter emerges from the pin OD and where it contacts the tang (or washer) is significant. It determines the length of the bending moment applied to the cotter, as such it is a direct factor in the bending load on the cotter.

[Pauls]

A halyard can sub for the forestay while you work on it.

[model 10]

Originally Posted by barnakiel

Why?

barnakiel

My guess would be so they are easy to remove in a hurry and also maybe re-use.

[Orion Jim]

Originally Posted by Guy

My guess would be so they are easy to remove in a hurry and also maybe re-use.

Yup. In those days everyone was parsimonious. Today we live in a disposable world. No one who removes a cotter pin would think of reusing it.....except for some of us old guys who are still parsimonious

[a64pilot]

If it's worth anything, I would never put a Clevis pin in place on an aircraft, without a washer under the cotter pin, but then I like to see a washer under a nut and bolt head as well.
The pin is is of course supposedly under shear load only, there should be no lateral force that causes it to "walk".
Should bees don't make honey though

A close tolerance fit washer on that pin would make it nearly impossible for the pin to fail, as is, I'd be uncomfortable.

[senormechanico]

Originally Posted by Sailmonkey

Hell, I bend the ends of the pin into a loop so they can't snag anything!

Especially ME when I'm near them.




Parsimoniously,

Steve

[UNCIVILIZED]

Were it me, I'd much rather at least pull the headstay, strip off the paint, polish up the stainless & break out the dye penetrant. That way I'd have a bit better idea of what is causing this, which IMO is one of those things which falls into the necessity category. Especially as usually when you see 1 thing wrong, there are several more. Which leads to... pulling the stick & inspecting everything. OCD, maybe. But I'd rather know that everything up there is okay, especially if any long trips are in order.

What's the history of the rigging? Meaning how old is it, when was the last time the stick was pulled & everything on it & connected to it was given a close inspection? And what sailing plans are in the near future?

As to removing the headstay so that you can take a look at things, a couple of halyards, that are in good shape, led forward is sufficient. And when you pull it off, inspect the wire's end fittings closely. Ditto the wire that's close by. Also, take a good look at everything else up there while you're inspecting things. Since again, there's rarely just one thing wrong, or in need of some TLC.

[theway]

Originally Posted by UNCIVILIZED

Were it me, I'd much rather at least pull the headstay, strip off the paint, polish up the stainless & break out the dye penetrant. That way I'd have a bit better idea of what is causing this, which IMO is one of those things which falls into the necessity category. Especially as usually when you see 1 thing wrong, there are several more. Which leads to... pulling the stick & inspecting everything. OCD, maybe. But I'd rather know that everything up there is okay, especially if any long trips are in order.

What's the history of the rigging? Meaning how old is it, when was the last time the stick was pulled & everything on it & connected to it was given a close inspection? And what sailing plans are in the near future?

As to removing the headstay so that you can take a look at things, a couple of halyards, that are in good shape, led forward is sufficient. And when you pull it off, inspect the wire's end fittings closely. Ditto the wire that's close by. Also, take a good look at everything else up there while you're inspecting things. Since again, there's rarely just one thing wrong, or in need of some TLC.

I'd love to do all of that, and maybe if I find myself in austrailia at a really nice marine with a lot of time and a similar OCD urge I'll do it. I do plan to make a more extensive inspection upon arrival in said marina.

I don't know the exact age of the rig, but everyone who gives it a once over comments on its adequacy. It was down in 2011 to be trucked from NJ to SF. I inspect it quite often at deck level and up the mast twice a year probably (On a good year).

I'm in Fiji now and will get across to Australia mid October and spend the year there (then continue west towards Africa). Maybe I'll at least get someone up there with more experience than me and also have them look around elsewhere to see if the mast should be pulled.

Thanks for the input.

[theway]

I just had the thought that maybe the tendency for this pin to be pulling out to the starboard side is due to thousands of miles sailed on the port tack. (Far less sailed on the starboard tack) Any rattling and shaking would simply help gravity do its work.

[UNCIVILIZED]

If either the pin or the hole is worn out of round, then the wear will accelerate with time. As the forces will be much more point loaded, instead of being spread out over much of the bearing surface of the pin & hole.

As to pulling the rig to inspect things, if it's been 6yrs, & you've gone from the US to Fiji, she could definitely do with that kind of TLC. As some highly regarded members here change their headstay every 4yrs, on the advice of several riggers. Since headstays take a lot more of a beating than any other standing rigging onboard. Well one's which are part of a furling system anyway.

Also, there are plenty of ways to pull a rig out without using a land based crane. Most of them quite low tech, KISS, & possible to use most anywhere.

[Blue Stocking]

Originally Posted by Sailmonkey

Hell, I bend the ends of the pin into a loop so they can't snag anything!

All good riggers cut the exposed cotterpin ends to 1/2 the diameter of the clevispin, open them to 30 degrees, and smear them with silicone.

[stormalong]

My experience is that tape on pins only holds moisture in and promotes corrosion/electrolysis.

I like to bend the pins into a loop so they do not snag anything. That makes them a pita to remove but I think it is worth it.

Brian
S/Y Storm Along

[barnakiel]

I only tape the toggle/pin. Not the mast. And our fitting is SS, not aluminum. Hence no visible corrosion there.

I too bend the split bin backwards. I have tested split pins a couple of times and found that only after about a dozen bend cycles (and I mean a tight radius / 90 degrees bend) the pin goes.

Buy a couple of identical split pins, use an identical cotter. Do a hammer me out test. I think that the risk (other than use of wrong material or size split pin) is next to nill.

Why does the pin pulls sidewise anyways? What is the physics behind such a pull?

I must re-read upwards as I asked about this 30 degrees folk story but I did not catch the explanation.

Cheers,
b.

[james247]

Originally Posted by barnakiel

I only tape the toggle/pin. Not the mast. And our fitting is SS, not aluminum. Hence no visible corrosion there.

I too bend the split bin backwards. I have tested split pins a couple of times and found that only after about a dozen bend cycles (and I mean a tight radius / 90 degrees bend) the pin goes.

Buy a couple of identical split pins, use an identical cotter. Do a hammer me out test. I think that the risk (other than use of wrong material or size split pin) is next to nill.

Why does the pin pulls sidewise anyways? What is the physics behind such a pull?

I must re-read upwards as I asked about this 30 degrees folk story but I did not catch the explanation.

Cheers,
b.

There is always vibration in the rig
. I put the blade of a screwdriver at the point where the pincome through the cotter pin hole and get a radius turn rather than a sharp bend of the split pin. This stops a pinch point on the split pin which can weaken it. I never use a split pin twice. They are so important and so cheap

[theway]

Originally Posted by james247

There is always vibration in the rig
. I put the blade of a screwdriver at the point where the pincome through the cotter pin hole and get a radius turn rather than a sharp bend of the split pin. This stops a pinch point on the split pin which can weaken it. I never use a split pin twice. They are so important and so cheap

That sounds like a good idea. Just to make sure I understand, you’re suggesting bend the whole pin, both legs in the same direction?

#1 in the image attached...