My Lower Forestay Fitting Ruptured Free Today In Heavy Wind

Status
Not open for further replies.
Jun 21, 2007
2,118
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
See the attached photos for the before and after of the failed piece.

I thought to post this experience for all that have older boats as I do. I bought my boat in 2007 with invoice evidence that the standing rigging had been replaced just a year (or so) before. And also I knew that the boat had been on the hard away from salt and sailing stress for almost the entire time since the work prior to my purchase.

I've read that standing rigging is supposed be good for a decade or so on average. But after some posts on SBO last year by Maine Sail and others about crevice corrosion to chain plates and other standing rigging connections to the actual boat, and also witnessing a boat returning from sea under power with it's mast dangling along the side, I soon thereafter commissioned a well-known SF area rigging firm to do an informal survey of my rig. A few items where highlighted ... but not the one that failed today.

Sailing on a close reach in strong winds that briefly had water over my port rail even though I already had the main on it's second reef point and a only 90% jib out, the wind suddenly shifted more towards a beam reach angle. (No real alarm about this though since instantaneous gusts and wind direction shifts are normal in the Hurricane Gulch area off Sausalito). About this same moment, a sound/shudder reverberated through the boat. Looking forward, I saw that the bottom of my furler drum/forestay turnbuckle was now trashing around on the leeward side of the boat forward of the forward lower shroud. After the initial "oh-crap-this-ain't-good" moment, but relieved that the mast was still standing, I changed course to a broad reach. Started the engine and throttled up to take some of the wind stress off the rig. Then engaged the auto pilot to maintain the broad reach course. I went forward to wrap my spare halyard around my bow sampson post. And got a line from my rope locker to tether the bottom of the forestay turnbuckle to the toe rail to stop the trashing. Then finally doused the main sail. Took a deep breath and hoped for the best while I made for my marina (or wherever safe anchorage). Closer to my berth, the wind calmed so I headed there and I was able to gather up a lot of the loose jib and wrap it more secure with a piece of line.

Doubt that I did it all right, but the boat made it back into the berth with the mast still up and a sense of the rig being safely secure.

I've attached a picture of the piece that failed. From an internet search, it's identified as a double jaw toggle. The smaller picture is a double jaw toggle in its normal state. This piece on my boat connects the lower turnbuckle bolt to the bow stem fitting. Several times over the years I did look hard at this piece. But only from the front. Where the break happened, on the back-side of the piece, both clean and rusted metal is evident. Sure indication of stress cracking and crevice corrosion.

My boat's wire rope and turnbuckles might have been new in 2005/2006 ... but it seems that other critical fittings were likely just assumed to be good without much inspection.

The only apparent damage to my boat is a slight bend in one of the furler extrusions and some scrapes along the cabin top into my just finished Interlux Perfection re-painting. (Maybe I should have spent just a fraction of the amount of time painting to instead inspecting my rig with crack detection dye!) After returning to my berth, I was able do a better job of securing the forestay in more-or-less its normal position using block and tackle led back to a primary winch to tension. I got the jib unfurled all the way out again. Upon which the sail did drop normally down the extrusion track and is now removed.

Guess my next step is to get my boat to a different rigger than I used before and have the entire rig taken apart and inspected per their protocol. Also demand that not only the standing rigging be checked but also every plate and connection and turnbuckle and bolt and pin, etc. (Ouch the $'s!) And today's new bend in the furler extrusion will need truing. Or likely time for a new furler anyway.

Returning home after this adventure, I added a strong gin tonic to my normal after-sail consumption of a couple of beers.
 

Attachments

JRacer

.
Aug 9, 2011
1,399
Beneteau 310 Cheney KS (Wichita)
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

Any landing is a good landing!
 

DougM

.
Jul 24, 2005
2,242
Beneteau 323 Manistee, MI
I am surmising that the fitting in your first photograph may not have been replaced at the time you thought that the standing rigging was done.
 

MSter

.
Apr 12, 2010
131
Sabre 38' MK II Oriental, NC
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

Wow! Nice save. Good description of your actions and a good reminder for all of us to be diligent always.
MSter
 

Ross

.
Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

That was a plain overload. Use a larger heavier replacement. Good emergency handling.
 
Aug 20, 2010
1,399
Oday 27 Oak Orchard
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

Have you inspected the failed toggle for evidence of fracturing prior to failure. I encounter this occasionally in the machine repair field. You can tell by looking at the fractured end by viewing the break directly. A dull apperance surrounded or in conjunction with shiny areas will give away prior defects. Should this be the case it might be prudent to replace any and all toggles that you have not already replaced. Nice bit of seamanship keeping the mast up. Keeping calm enough to assess and manage the situation is sailing at its' best.
 
Jun 21, 2007
2,118
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
Have you inspected the failed toggle for evidence of fracturing prior to failure. I encounter this occasionally in the machine repair field. You can tell by looking at the fractured end by viewing the break directly. A dull apperance surrounded or in conjunction with shiny areas will give away prior defects.
Didn't inspect too critically yesterday. But yes what you describe is evident. The now exposed cross sections where the piece cracked show both clean silver metal where presumably the crack ripped through "good" metal and rust tarnished sections where the pre-failure cracking must have been happening for a good while. The surface of the front side of the toggle looks virtually as new.
 

Ross

.
Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

The shear strength of the pins far exceeds the tensile strength of the straps in the stamping.
 
Aug 20, 2010
1,399
Oday 27 Oak Orchard
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

These are the worst failures. Virtually without Xrays the fracture isn't evident until failure. Worst of it is the diagnostics to detect imminent failure cost more than the part. Something all of us need to consider as our boats age.
 
Jun 21, 2007
2,118
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
Here's a picture of the double-jaw forestay base toggle that failed on my boat July 4th.

Also a photo of my no longer straight extrusion assembly. I'll take another look at it next time at the boat. Maybe only three sections are bent. The drum and head of the furler both still rotate normally. Speaking with Profurl, seems that replacing the damaged extrusions should yield a successful long-term repair outcome.
 

Attachments

May 26, 2004
168
- - Oriental, NC
Could you take a head on shot of both of the fracture faces filling as much photo as possible with the image. May want to light from the side with a flashlight. Thanks

Goodwinds
DaveM
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Here's a picture of the double-jaw forestay base toggle that failed on my boat July 4th.

Also a photo of my no longer straight extrusion assembly. I'll take another look at it next time at the boat. Maybe only three sections are bent. The drum and head of the furler both still rotate normally. Speaking with Profurl, seems that replacing the damaged extrusions should yield a successful long-term repair outcome.
That's simple overloading. The Schaefer part looks WAY small for a 36 foot boat.
 
Jun 21, 2007
2,118
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
That's simple overloading. The Schaefer part looks WAY small for a 36 foot boat.
Hi Jack:

Actually the failed piece is on the larger side of the Schaeffer size chart. A 1/2" pin. Really a pretty robust piece. The next size up I think may have been too wide to fit into the confined area of the head stem piece. Not shown well in the picture is that the cross sections along the breaks are a mix of rust on one side and clean metal on the remainder. This was long term stress fractures and corrosion which finally blew apart. The toggle probably should have been replaced when the boat was last re-rigged. Maybe it was on the boat of a couple of decades or more. The 1/2" pin shows wear as well. The outside of the forging, which was easily viewed, only showed clean shiny metal last year when it was visually inspected. Ever since I owned the boat I have maintained adequate forestay/backstay/shroud tensions to avoid impact stresses with wires going slack and tight frequently. Maybe a PO (or two) sailed with things too loose?
 

higgs

.
Aug 24, 2005
3,736
Nassau 34 Olcott, NY
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

The Cheubini 36 is a cutter rig, isn't it?
 
Dec 2, 2003
766
Hunter 260 winnipeg, Manitoba
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

Rardi. From the photo it looks like that part is fixed in the fore-aft orientation with a aftward pull on the pin at the top? My understanding is that type of fitting is meant to pivot in two dimensions so that the pull is linear through the fitting. Might just be my misinterpretation of the photo!
 
Jun 21, 2007
2,118
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
Could you take a head on shot of both of the fracture faces filling as much photo as possible with the image. May want to light from the side with a flashlight. Thanks

Goodwinds
DaveM
Dave:

My camera never was good at taking super close-up. Best I could do. Same break different angles.
 

Attachments

Apr 8, 2010
1,606
Frers 33 41426 Westport, CT
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

You can really tell it was cracked and corroded through almost half the material in those close ups... The deformation and eventual ripping of metal is clear on the right 1/3rd, where the left 1/2 was probably cracked for months...
 
May 26, 2004
168
- - Oriental, NC
Rardi

I took a shot at a failure analysis from the pictures you posted. Good job on the detail fracture photos. See if I have the orientations and positions right. If not then let me know what is wrong and I will take another shot at it. I think we can all learn something from this post. Thanks.

Goodwinds
DaveM
 

Attachments

Aug 20, 2010
1,399
Oday 27 Oak Orchard
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

Fantastic photos of the fracture. We see this when long term fracturing has occured in machinery. Had this same exact situation on a punch press 2 weeks ago. Simple metal fatigue over an extended period of time. Interesting in that the remaining metal held for as long as it did. Obviously the toggle had excess strength to absorb that 50% loss prior to failure.
 
Jun 21, 2007
2,118
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
Re: My Lower Forestay Fitting Ruptured Free Today In Heavy W

Dave:

Just got to a mountain destination after a long drive. And dinner for me/wife is the first priority. Hope that you can excuse my not taking a look at your pdf until tomorrow morning? Thanks for your interest ...

rardi
 
Status
Not open for further replies.