Another forestay failure/mast crash

[Hardcrab]

Seacatcap,
I agree with you and the others.

The toggle will act like a U-Joint because it adds a different 90* freedom of movement axis, left and right, without bending/stressing the loop.
As it is, only an up/down movement (rotation of the loop thimble/shackle pin), is available with the current set-up.

It took me awhile to get my brain around this, but it's clear now.

So far, I've located a 3/8" toggle (needed for the shackle pin/ loop diameters), but it's almost 2" long - center to center.

That may be a problem with making the stock forestay "too long" .
I don't think I have the extra 2" of take up in the turnbuckle under the furler drum.

I could just rake the mast back a few degrees to use up some of the the extra length, but I like my mast angle where it is now at 90 degrees.

So far I'm leaning to to go with another factory 1/8" forestay, (with a toggle if I can make it work), for now.
Then later, after the dust settles, go further with the pros/cons for a 5/32" upgrade.

But please, this is still open for any discussion, which might help everyone interested.


Also, I should add to the thread the results of a few phone calls to folks who know this boat well.
(Very vested interest I should add)
They both remarked that incorrect mast lowering/raising/trailering can accidently put a kink in the stay resulting in premature failure.
Not my case at all, but understandable.
More to my case was the THEORY that my genny sock, flapping in the wind while on the trailer, can cause 24/7 mini shock loads causing the early fatigue failure.
I'll need to sleep on that.
Both sources remarked the larger 5/32" upgrade as "not needed".
Also both sources had neutral responces to the toggle----'not needed on this boat", even after I mentioned what the CDI book says.

[bscott]

Even a tight fitting genny sock--or a loosely furled jib will vibrate and damage the furler and forestay.
5/32" wire on my boat with at least 4 wraps of the jib sheets around the furled jib.

Bob

[bluehawk]

For what its worth, my forestay failed after 5 years as well, right under the thimble. I too had a jib sock over the jenny for the 5 years, and I noted in high winds there was a lot of flapping and vibration. One night a year and a half ago we got high winds measured at around 50 kts, and our M was slipped at a marina, we were not there, but got the call the next day that our mast was hanging over the aft of the boat, and either during the fall or with repeated movement of the boat, the mast bent, along with the spreaders, and it also put stess on the shrounds. The only good news was it was at the end of the season, so I got a replacement mast, spreaders, shrounds from BWY, and put humpty together again, albeit this time with a 5/16" forestay, if nothing else to give me some piece of mind. Needless to say, I don't use the jib sock, and had UV protection sewn in the genny.
Dean

[c130king]

I really hate reading these threads...

Original 1/8" forestay and CDI furler system...6 years old.

Genny sock...got it

Thimble thing-a-ma-jig...not sure

Mast up storage on trailer so rarely get to check this connection up close...yup

It's amazing I am not bald from all my worry-warting...

But the mast is coming down (on-purpose...) on the weekend of 6-7 August and I will give this a thourough checkout.

Cheers,
Jim
(* AKA - Mr. Worry-Wart *)

[Hardcrab]

Mr Worry-Wart ,
Consider using a good magnifier and look as deep into the upper nicopress swage as you can.
Look for hairline cracks across any of the nineteen (38) strands that you can see.
I would think to get the best all around viewing, the the stay is removed from the shackle and looked at in hand.

Once again in my case, of the nineteen strands, only seven were shiny at each side of the broken ends.
The other twelve ends were darker, also on each side, indicating (??) that they were broken for a longer time than the last seven that must have broken all at once.
Perhaps with a better look, some of the darkened ends may show different shades of "dark", pointing to a time difference among the broken twelve.
Only a few strands must break at a time until it gets to the last few.

None of the strands were flying loose or laying "wrong" in the loop when I inspected mine two weeks prior to the break.
It looked fine, although I did not know how or what to look for other than obvious fraying, loose strands.

Also, I just ordered the needed replacement stuff from BWY from Cheryl.
She remarked that the same 1/8" forestay construction methods have been used on the X over the years.
Exact same.
Only the M's have shown the history of breaking forestays in her memory.
If her recollections are correct, then dis-simular metal corrosion could be taken off the table as a factor?
Have any X guys seen this?

What else has changed between the X and M leading to some early failures?

[Sumner]

....What else has changed between the X and M leading to some early failures?

After what you guys posted about the M and its rotating mast and how that will turn that shackle side to side I guess that if it is a bigger problem on the M vs. the X then that might be a factor.

If the first strands to break seem to come on the sides above the nicopress and below the thimble and the last to break are on the front and/or the back of the forestay in that area then that might lead to the assumption, right or wrong, that the rotating mast is a function.

Just a thought,

Sum

Our Endeavour 37

Our Trips to Utah, Idaho, Canada, Florida

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[restless]

I witnessed an M lose her foresails last year, and interestingly enough the stay broke right through the top of the thimble! I was utterly astonished.
As an owner of the superior X I am not immune to these issues. After our first outing I had a close look at this item and saw that there were 2 strands holding all up for the last few hours of pottering about.
I upgraded a size and had a stainless long shanked eye swaged on. I also always lower the mast with tension on the forestay (to keep it WELL straight) and unclip it as soon as I can. To often it has a nasty tendency to kink at that point. I struggle to imagine anything worse than getting a spreader in your face when out for a wee jaunt.
Hcrab.. you seem to have been pretty unluckily lucky if you get my drift. Now you'll be an M expert

[mike uk]

Question:-

Would the use of flexible stainless steel wire be a good idea for the shrouds and particularly for the forestay?

I've been told it has the same strength as normal s.s. wire but it is flexible so that it can be used in pulleys in machinery etc.

Presumably it would be much better at coping with awkward stresses when raising the mast?

Mike

[csm]

I guess it was serendipitous that our 2001X's PO was less than compulsive about caring for the boat. He left the furler hanging over the bow with the jib attached. The furler foil was severely bent, and broke when I tryed to straighten it. The leech and foot of the jib also were sun rotted. Being a resourceful and frugile sort (tightwad), I decided to shorten everything up. Trips to the local loft and rigging shops, and a less than a boat buck and I had an almost brand new (but slightly smaller) jib and furler. I had the riggers make up another forestay that attaches to the mast at the original location, and installed another bail about 30" below for the furler forestay, resulting in dual forestays. The added bonus is that when I trailer, I move the furler to the upper bail and the drum lays flush with the bow. I put a break over mechanism on the furler for quick and easy pinning, and tweak the longer forstay with the turnbuckle. I may not have the optimum tension in either forestay, but we sail fine and the redundant forestay give me a very warm fuzzy feeling.

[Judy B]

Hamin X,
Thanks for the reference.
I'm guess hard-headed.

At first glance, it looks like the added toggle just lowers the same forces seen on the nicopress/loop.
Instead of the "twisting forces" in the existing hound/setup, this just shifts the same twisting forces to the toggle, to my thinking.

No net change overall?

But I'll add it anyhow, as per the CDI manual.
Interesting.
The PO/dealer did not do this step.
It's as I got it.

Is this the common thread with the mast crashes seen on this forum??

Yes, the toggle transmits the bending moments from the wire/nicopress junction to the pins in the toggle. The toggle of the forestay acts as a "universal joint" which permits the swage at the top of your forestay to move fore and aft, laterally, and up and down as the headsail bends and pulls on the forestay. The forces are the same, but the structural members (pins) bearing them are moving freely against each other, not flexing.

Without a toggle (or something analogous that provides 5 degrees of freedom in translation and rotation), all the forestay "sagging" and wiggling from windage gets focused where the cable enters the swage, and the bending at that point causes metal fatigue leading to failure of the forestay. If there is no toggle attaching the forestay to the mast hound, the individual wires will soon become brittle and break where they go into the swage.

You don't need to install a toggle at the bottom of the forestay because there is one built into the drum of the CDI.



Hope this clarifies,
Judy B

[mtc]

Having experienced a forestay failure on a hobbie and seeing the mast come down in very fast slow motion . . . one of the first things I did to bellaroo was to rig a secondary forestay that attaches to a second point above the stock location. I think I have pics of my mod here, but as it's been a bit of time since posting, I don't recall. Will review what I have posted and see if I have a few pics to load.

I can't imagine sailing without it. It's a safety feature having redundancy on keeping the mast upright. Having it fall forward from a failed backstay is one thing, but having it fall on my lovely bride's head is another.

Michael

[romandesign]

How are you guys using MRS wire tied to pullpit as a secondary backup forestay? My 26D has it attached to the same bolt as the forestay with furler, so I tried it but it gets caught when rolling the furler, so I had to remove it. Is there a way to tie it so it doesn't get in the way?

[Highlander]

If you have a cdi furler then just use ur foresail halyard as a backup by attaching it to ur bow pulpit if ur forestay fails only ur headsail & furler will fall into the water. Ur forestay will fail sooner than later if you do not have a swivel on the top of it the forces on it pulling forward. Backwards & sideways r constantly twisting it. So adding a swivel it takes all the twisting & stress. Not the cable

J