PDA

View Full Version : What's wrong with this shackle?



Woxbox
12-14-2011, 07:10 PM
I've been going over my 24-year-old boat replacing all the worn-out parts. When I got to the shackle at right below, I figured better to replace it before it busts at an inopportune moment. It secured the mainsheet to a tang on the end of the roller-furling boom. As you can see, the tang was wearing on it.

So I did a bit of shopping. The original is a Wichard.
Wichard - $46.99
Ronstan - $41.22
Suncor - $14.47

I bought the Suncor, pictured at left. What's wrong with this shackle that it's so much cheaper? Is it made in China? (I couldn't find any stamp on it or mention on the Suncor website of where this hardware is made.) Is there something inferior about it that I can't see? It is actually a beefier shackle than the Wichard.

I'll use it for a season and examine it for wear. But it does seem too cheap to be true. Has anyone else tried Suncor hardware? They have an extensive catalog.



http://i45.photobucket.com/albums/f92/Woxbox/shackles.jpg?t=1323910843

J. Dillon
12-14-2011, 07:31 PM
But it does seem too cheap to be true.

I think you answered your own question.;)

BTW, What ever happened to Brummel shackles ? The kind that mated with a similar member with an narrow chisel opening on or off an opposing member.

JD

Larks
12-14-2011, 08:18 PM
I've been going over my 24-year-old boat replacing all the worn-out parts. When I got to the shackle at right below, I figured better to replace it before it busts at an inopportune moment. It secured the mainsheet to a tang on the end of the roller-furling boom. As you can see, the tang was wearing on it.

So I did a bit of shopping. The original is a Wichard.
Wichard - $46.99
Ronstan - $41.22
Suncor - $14.47

I bought the Suncor, pictured at left. What's wrong with this shackle that it's so much cheaper? Is it made in China? (I couldn't find any stamp on it or mention on the Suncor website of where this hardware is made.) Is there something inferior about it that I can't see? It is actually a beefier shackle than the Wichard.

I'll use it for a season and examine it for wear. But it does seem too cheap to be true. Has anyone else tried Suncor hardware? They have an extensive catalog.



It may simply be the cost and quality of the stainless steel. We've been getting quite a few Chinese 316 stainless items in here and although a few years ago the quality of the stainless had been questionable, I've not heard any similar concerns recently, the most recurring problem now being more to do with the quality of casting and so on. On those shackles the it seems to be the springs rusting because they are not 316 or another marine grade stainless steel springs, or problems with the shackle opening and closing easily at the pin end due to the angle of the pin or quality of casting.

Peter Malcolm Jardine
12-14-2011, 08:32 PM
The Wichard is forged, the Suncor is cast. The safe working load on the Wichard will be significantly higher than the Suncor. The alloys that Suncor use are fairly good I think, but the Wichard is the gold standard. Fair to mention, I have several pieces of Suncor stuff in use and no failures or complaints so far.... Small boat use only ... Looks like bronze in those pictures... but the rules in stainless apply also.

sealrock
12-14-2011, 08:36 PM
With cheaper hardware looks can be decieving. Hidden flaws in the casting can cause failure with no notice. If you are considering using this brand hardware in the future (I would be tempted to, because of the price) Purchase an extra "specimen" for destructive testing, ie put in a vice and beat on it with your biggest hammer, If it fractures or breaks cleanly, metal used is unsuitable for the application. However if the metal bends or distorts instead, I would consider it suitable for light duty use. This test should give an indication of the standard the hardware is manufactured to.

Woxbox
12-14-2011, 08:41 PM
The safe working load of the Suncor is listed at 1,000 pounds. The Wichard is listed at 1,763. But in this application, wear is the issue, not the maximum load. And the Suncor appears to have a thicker bail. Wichard also claims that their forgings will deform before they break. Suncor only argues that their 316 stainless is good for the marine environment. But you've got me wondering about the spring. (Both items are stainless - the light in the photo is off.)

JimConlin
12-14-2011, 09:13 PM
Maybe it's the alloy. I recollect that the fancy snap shackles from Wichard and Ronstan/Nicro/Schaefer... were 17-4PH stainless. The Suncor item is 316.
I don't know what this might mean. Maybe someone will enlighten us.

I've used other Suncor deck cleats (blue water pattern) and Skene chocks and they've been OK.

I'd keep a $6 carabiner in the junk box.
http://www.rei.com/zoom/471041Lrg.jpg/150

Larks
12-14-2011, 09:38 PM
Maybe it's the alloy. I recollect that the fancy snap shackles from Wichard and Ronstan/Nicro/Schaefer... were 17-4PH stainless. The Suncor item is 316.
I don't know what this might mean. Maybe someone will enlighten us.

I've used other Suncor deck cleats (blue water pattern) and Skene chocks and they've been OK.

I'd keep a $6 carabiner in the junk box.
http://www.rei.com/zoom/471041Lrg.jpg/150

I'm no expert but I understand that 17-4PH is a reasonably high strength SS but does not have a particularly high corrosion resistance, more comparable to 304SS than 316 SS in corrosion resistance.


Edited to add, just found this in Wiki:


Precipitation-hardening martensitic stainless steels have corrosion resistance comparable to austenitic varieties, but can be precipitation hardened (http://en.wikipedia.org/wiki/Precipitation_hardening) to even higher strengths than the other martensitic grades. The most common, 17-4PH (http://en.wikipedia.org/w/index.php?title=17-4PH&action=edit&redlink=1), uses about 17% chromium and 4% nickel. The Lockheed-Martin Joint Strike Fighter (http://en.wikipedia.org/wiki/Joint_Strike_Fighter) is the first aircraft to use a precipitation-hardenable stainless steel—Carpenter Custom 465 (http://en.wikipedia.org/w/index.php?title=Carpenter_Custom_465&action=edit&redlink=1)—in its airframe.

Austenitic varieties include 316 and 304, but I would never use 304 in a marine environment so I'm not sure about the reference to corrosion resistance with the 17-4PH as I am pretty sure that it is more comparable to 304 SS in regards to corrosion resistance, which would contradict Ronstan etc using it???????. You have me on a quest to find out more now!!


Edited yet again to add:


Precipitation hardening stainless steels have moderate to good corrosion resistance in a range of environments. They have a better combination of strength and corrosion resistance than when compared with the heat treatable 400 series martensitic alloys. Corrosion resistance is similar to that found in grade 304 stainless steels

Roger Cumming
12-14-2011, 11:35 PM
Is a snap shackle the proper fitting for attaching the mainsheet to the boom? If you attach it at the beginning of the season and un-snap it at the end of the season it's not the right fitting. Snap shackles are for fittings that are frequently connected and disconnected, like sheets to sails. A regular shackle may be more appropriate - one that screws together. You may be trying to use the wrong type of fitting, a snap shackle, which is inherently expensive because of its quick release feature, where a regular screw shackle is would be more sensible. Think about that boom wacking you upside your head when you are tempted to buy cheap boat hardware, especially fittings from an unknown source whose failure could be inconvenient or even dangerous.

Woxbox
12-15-2011, 09:17 AM
I keep the boat on a trailer, so the shackle does get taken off and put back on routinely. But I started this thread wondering what others gauged the risk of total failure to be. The boom is too high to wack me on the head, but under the right circumstances it could feasibly take out a cap shroud, at which point the top half of the mast might snap off. The shackle itself looks every bit as well made if not better than the Wichard. It's actually a heavier piece, and note that the swivel is much beefier on the Suncor than it is on the Wichard. If I hadn't known, just looking at them I would have guessed the Suncor to be a more expensive piece of hardware. Granted, the fact that the Wichard is forged is an invisible but very significant difference.

Figment
12-15-2011, 09:20 AM
It looks to me like the geometry is different. This may not matter for your application, but the shackle on the left will be significantly more difficult to release while under load.

G.Sherman
12-15-2011, 09:39 AM
Could the worn shackle be reconditioned by brazing new material on and finishing with a needle file?

Ian McColgin
12-15-2011, 09:42 AM
I was thinking the Suncor, with the pin at a flatter angle and the load closer to the pivot, would be easier to open. Don't know if it would be too easy.

Suncor actually has, so far as I've heard, a good rep. I know that at least some of their products are domesticly manufactured and they lay claim to superb quality control. The traditional problem with the far eastern hardware of a generation ago was that the alloys were wrong and the casting process poor and Suncor's claims about alloys and product testing obviates that no matter where the stuff is made.

Figment
12-15-2011, 09:53 AM
The load is closer to the pivot? If so, then it's bad design, the load should be on centerline of the swivel I'd think.

The horizontal pin may or may not make a difference, it's in pure shear either way.

Bruce Hooke
12-15-2011, 10:02 AM
It seems to me that the difference in load capacity and the difference in how they are made explains most of the difference in price. Plus, the fact that the Suncor is cast while the Wichard is forged explains the difference in the thickness of the parts. Castings being inherently weaker they presumably had to make the parts thicker to compensate, but this was not sufficient to get anywhere near the strength of the Wichard. On the other hand, on a lot of small boats it seems like parts like this are often sized more for convenience than for load requirements.

Bruce Hooke
12-15-2011, 10:04 AM
The load is closer to the pivot? If so, then it's bad design, the load should be on centerline of the swivel I'd think.

Yes, if you assume that pivot is the critical part in terms of the strength of the shackle. On the other hand, putting the load closer to the pivot should make the shackle easier to open under load.

John E Hardiman
12-15-2011, 10:19 AM
I'm no expert but I understand that 17-4PH is a reasonably high strength SS but does not have a particularly high corrosion resistance, more comparable to 304SS than 316 SS in corrosion resistance.

Austenitic varieties include 316 and 304, but I would never use 304 in a marine environment so I'm not sure about the reference to corrosion resistance with the 17-4PH as I am pretty sure that it is more comparable to 304 SS in regards to corrosion resistance, which would contradict Ronstan etc using it???????. You have me on a quest to find out more now!!

Corrosion resistance is a very touchy subject, because it is so conditional. 17-4ph has corrosion resistance comparable to 316L PROVIDED you don't set it up with a crevice corrosion cell. 17-4 needs oxygen, lots of it, to keep it's passivation coating. It works great as a rigging or airframe item, not so good as a bedded deck fitting or underwater (I've seen a 3" thick fitting fail in less than 3 months).

And 316 is also a dangerous material if you don't know what you have. Depending on the heat treating and forming atmosphere, 316 strength and corrosion resistance can be all over the place, somethimes making it even worse than 302/304/308. If you really need strength, formability, weldability, and corrosion resistance, you need to specify 316L or ELI. FWIW, we are seeing a lot of fittings being made out of 308 (more chrome, less nickel so cheaper and can more easily be made from scrap), and with the more chrome it polishes up better. However, like 316 and the others, it needs to be soak annealed after forming. Put a magnet on the piece, a proper annealed piece will not be magnetic, an as wrought piece will be slightly so.

rbgarr
12-15-2011, 10:30 AM
Not an answer to your question, but I'd be inclined to use a shackle with a captive pin and detent instead of a snap shackle for that purpose, especially if the snap pin has a ring on the end. Those can catch on things and get sprung open at 'inopportune' times. (damhikt |;))

http://www.ebay.com/itm/NR-Lightly-used-New-Stainless-Wichard-Mainsail-Locking-Shackle-2-Long-/230717302597?hash=item35b7d2a745&item=230717302597&pt=Boat_Parts_Accessories_Gear&vxp=mtr

J. Dillon,

I LOVE Brummel hooks, especially the old bronze ones, but they are a hard to find now. They are good for sheets on jibs and spinnakers that have to slide around forestays and shrouds. They don't catch and yank like some other fittings do. But I suspect they fell out of favor because they were expensive to machine and perhaps, just perhaps, were too 'puzzling' for some to figure out how to use. Now these 'sister clips' are what have replaced the bronze and aluminum ones on the market:

http://www.ebay.com/itm/STAINLESS-STEEL-SAILBOAT-FLAG-LINE-SISTER-CLIPS-2-SETS-/330476479300?hash=item4cf1eee344&item=330476479300&pt=Boat_Parts_Accessories_Gear&vxp=mtr

Garret
12-15-2011, 11:34 AM
I keep hearing about metal fittings (of whatever type) for jib sheets in this thread. Ever get hit in the head by one? I have brummel hooks for my running backs, but all jib/staysail sheets use a bowline or single line with whipping. Just my opinion, of course.

For the main sheet on my little trailer boat, I use a snap shackle & it's done fine. I like the ease of disconnect/reconnect.

rbgarr
12-15-2011, 11:37 AM
I can well imagine that on your fifty footer, Garret! Not so much on a smaller blade jib like mine.

Garret
12-15-2011, 12:11 PM
I've been hit by shackles on Blue Jays (mini-Lightning for those unfamiliar) & they hurt like hell! Especially when you lean over & it cracks you right in the temple.... DAMHIKT

Rapelapente
12-15-2011, 12:29 PM
The forged vs cast construction aside, the Wichard is french made, so the load capacity announced is credible, and controlled.
And of course the cost is higher.
With Chinese stuff, you get the price, but when it's about safety devices....
http://www.wichard.com/documents/marinegb.pdf

outofthenorm
12-15-2011, 02:42 PM
If it was a component in something life-critical, I would worry over a thing like this. But for a mainsheet on a trailer size boat? It likely won't fail for 20 years and if it does, no biggie. Buy two and have a spare.

- Norm

Woxbox
12-15-2011, 03:38 PM
If it was a component in something life-critical, I would worry over a thing like this. But for a mainsheet on a trailer size boat? It likely won't fail for 20 years and if it does, no biggie. Buy two and have a spare.

To me, this seemingly simple decision is a microcosm of what building or maintaining a boat always comes two. I can buy two cheap shackles for less than the price of one gold-standard shackle and have a spare. You can also argue that every item on a boat is a safety item. But with that logic, costs easily double or triple.

I estimate the loads on the mainsheet register in the hundreds of pounds, but not so much as a thousand, (it's about a 280 sq. ft. full batten sail on a bendy mast) so I doubt this shackle would give, and it probably isn't the weakest link in the chain of hardware that links the boom to the traveler car anyway. So since no one has screamed that Suncor stuff is unreliable junk, I'm going to give the shackle a season and see how it holds up. If I lose my mast or my head, I'll let you know.

Nicholas Carey
12-15-2011, 04:38 PM
The Wichard is forged, the Suncor is cast. The safe working load on the Wichard will be significantly higher than the Suncor. The alloys that Suncor use are fairly good I think, but the Wichard is the gold standard. Fair to mention, I have several pieces of Suncor stuff in use and no failures or complaints so far.... Small boat use only ... Looks like bronze in those pictures... but the rules in stainless apply also.

Looks like Suncor make 3 stainless steel models with a clevis pin swivel: http://www.suncorstainless.com/heavy-duty-jaw-swivel-snap-shackle

Their website lists WLL -- Working Load Limit aka (I believe) Safe Working Load (SWL) -- as

2-3/4 in model: 1,000 lbs
3-1/2 in model: 1,500 lbs
5 in model: 2,000 lbs

compare to Wichard's equivalent models, again with a clevis pin swivel:

70mm/2-3/4 inches: working load 800kg/1,763 lbs, breaking load 1600kg/3527 lbs
90mm/3-1/2 inches: working load 1,280kg/2,822 lbs, breaking load 3800kg/8,378 lbs
120mm/4-3/4 inches: working load 2,400kg/5,291 lbs, breaking load 7000kg/15,432 lbs

So, comparing the working load specs, we see that the equivalent Wichard models are, respectively 76%, 88% and 164% stronger than their Suncor equivalents. Conversely, you could say that the Suncor products are, respectively, 43%, 47% and 62% weaker than their Wichard equivalents.

outofthenorm
12-15-2011, 06:37 PM
That's good data. However, at even half of those strengths, each one would be more than required to do the job safely and for a long time. Personally, I would replace the whole set up with a loop and toggle. Make it rope and wood if the boat is traditional, wire and SS it it's not. Cost next to nothing and can't bash you on the temple.

- Norm

Woxbox
12-15-2011, 08:58 PM
So, comparing the working load specs, we see that the equivalent Wichard models are, respectively 76%, 88% and 164% stronger than their Suncor equivalents. Conversely, you could say that the Suncor products are, respectively, 43%, 47% and 62% weaker than their Wichard equivalents.

Exactly so. But 76% the strength at 1/3 the cost. If you work it backwards from the strength you need, or if you look at working load/dollar, then the Wichard shackles don't come close. The mid-size Suncor is selling for $18.28 at Jamestown. That's 1,500 pounds of working load for that price, compared to $46.99 for something very close from Wichard.

I'm not arguing at this point that one solution is better than the other. I'm just surprised how much variance there is in the price. Here's another anomaly -- these simple Dyneena soft shackles at Jamestown sell for $19.75 and up. They're not suited for my mainsheet, but the price for a short piece of Dyneema with a knot tied in it makes no more sense to me than a complex piece of polished stainless with moving parts does that goes for less.

http://images.jamestowndistributors.com/images/large/63895.jpg

J. Dillon
12-15-2011, 09:14 PM
Well, if ya going to go the simple route, why not a seperate eye splice and toggle ?
|;)


JD

Woxbox
12-15-2011, 09:21 PM
JD -- I am thinking of converting all the standing rigging to Dyneema. Goodbye turnbuckles, hello deadeyes!

J. Dillon
12-15-2011, 09:29 PM
To KISS is devine.:D

JD

JimConlin
12-15-2011, 10:35 PM
JD -- I am thinking of converting all the standing rigging to Dyneema. Goodbye turnbuckles, hello deadeyes!

It's amazing stuff. I've found several uses- lashings in place of shackles on blocks, steering lines in place of wire, and a heavily loaded main halyard.

Bob Cleek
12-16-2011, 12:13 PM
Exactly so. But 76% the strength at 1/3 the cost. If you work it backwards from the strength you need, or if you look at working load/dollar, then the Wichard shackles don't come close. The mid-size Suncor is selling for $18.28 at Jamestown. That's 1,500 pounds of working load for that price, compared to $46.99 for something very close from Wichard.

I'm not arguing at this point that one solution is better than the other. I'm just surprised how much variance there is in the price. Here's another anomaly -- these simple Dyneena soft shackles at Jamestown sell for $19.75 and up. They're not suited for my mainsheet, but the price for a short piece of Dyneema with a knot tied in it makes no more sense to me than a complex piece of polished stainless with moving parts does that goes for less.

http://images.jamestowndistributors.com/images/large/63895.jpg

$19.95 and up! Holey Moley! If you need more than a couple, you'd be better off spending the money on a copy of Ashley's and making up your own. They're going in the right direction, though. A good rule to follow is to never use a metal (or, gott forbid, plastic) connecting fitting where a knot will serve as well. Lighter weight and much safer, as mentioned above. Headsail sheets are best fastened to their clew with with a double bowline on a bight at the middle of a single length of rope. One loop of the double bowline is made up smaller than the other. It goes through the clew first and the longer loop is then passed through it on the other side of the cringle. The smaller loop should be just large enough to pass through the cringle and allow for the longer loop to fit through it. This knot will not shake loose and will not hang up on stays and shrouds when tacking. It also won't leave marks when a luffing clew smacks you upside the head... and it doesn't cost a dime.

If you are a racer, save your snap shackles for headsail halyards and tack pendants. A hunk of metal on the end of a line whipping around at sea is a deadly weapon.