shackle locking

tyce

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when i checked my mooring yesterday the hole in the shackle pins had corroded right through due to the stainless wire i locked them with.
i am using tie wraps at the moment, but is there something more wear resistant i could use.
 
I worry about this (amongst other things)
I've tried the stainless wire and cable connectors and had both fail. Some forumites reckon black B&Q cable connectors are UV resistant (or was that weren't UV resistant?).
The contractors who lay the moorings on the lake just use a nylon cable connector as well as a lot of welly when they tighten the pin.
I've taken to peening the end of the pin as well to distort the threadsas a precaution.
Frighteningly I used some chain from the riser to my fore deck as a strop as well as a nylon strop. When I inspected it the foredeck end of it was fine but the underwater bit was very corroded. In just one year in fresh water.

This is the two ends on a 7ft length of chain
wornchain.jpg


My nylon strop (2 years old) is fine, so I've bought a second one and junked the chain. I've also gone up on shackle size.

This was the 3 year old riser

wornchain3.jpg


Happy to say the wardens have upped the spec for these now. The shackle on the swivel with the long cable tie is the one the contractors put on, and it's their cable tie.

Newchainriser.jpg
 
I had the same problem and eventually used the strongest commercial loc-tite + cable tie + peaning the outer threads - that worked! I was considering araldite, cause when it does work, it is then sometimes faster to use a grinder to remove it!
 
NEVER use stainless steel full time immersed in water

NEVER use stainless steel full time immersed in water.. I can post several photos of broken stainless steel swivels or shackles

And CAREFULLY check the working load too. Here is a photo of a swivel with a published break load of 10800kg.

swivel.jpg


At 2000kg the pins had bent to the point they would not come out again and the 12mm centre bolt (in a 16mm swivel ????) had stretched a bit so it was as good as useless by now. We then took the swivel to a Proof Load of 4000kg and you can see the results.

The swivel should have gone to at least 5400kg, being 1/2 published break load, without any signs of stress. I reckon the pictured swivel would take probably only another 500kg max to tear it to bits.
 
We have 3 swivels. One on the sinker block. Then an enormous chain (about 6" links and almost an inch thick) to another swivel then the swivel at the top of the riser chain. We don't get wound up much, but the twin strops can get twisted in very calm conditions when the bow hangs over the buoy.

That's the big chain on the barge deck

Sinkerchain.jpg


Some people moor to the ring, but I prefer to moor to the chain.

newmooring1.jpg
 
Underwater where UV is not a problem I now use 2 or 3 cable ties to stop the pin rotating. To stop the chain wearing through the cable ties I fit a large plastic washer onto the shackle pin between the chain and the cable ties. A plastic food chopping board is a good material (polyethylene I think) for the washer. It is about 10 mm thick and I make the washer diameter about the width of the chain links so that they cannot work their way past the washer.

On the underwater shackles I smear a good coating of cheap general puppose oil based mastic on the threads and also where the pin passes through the other eye of the shackle. The mastic stops the threads corroding (which can be a cause of the pin falling out) and it does not set so it makes the removal of the pin with a wrench quite easy even when done up tight. With mastic I have found no tendency for the pins to undo on their own so the cable ties are an extra precaution.

Above the water where UV is a problem but corrosion is less I use monel wire. On the treads I have found Lanocote (lanoline) lasts well out of the water and it is much less messy than the mastic.
 
Nip the shackle up very tight then the 2 mill of male thread that is showing at the other end of the shackle pin dress down with a hammer so there is no way the thread can turn back through the female thread.

Paul.
 
Some of these suggestions are all well and good.... but for me it is slightly more difficult... I have to attach my bridles to an existing mooring buoy/chain with shackles... so it means attaching the shackle/bridle whilst on the water... a little trickier.

The buoy etc is provided by the club, I just have to attach my own bridles for mooring, if anyone was wandering.
 
We just use cable ties - having nipped up the shackles tight ... put a cable tie through the hole in the pin, around the body of the shackle and tighten up... 6 months and we're taking the headgear off again, not lost a cable tie to UV yet - nor has the shackle tried to come undone for that matter (but why risk it eh?!)
 
For one thing, never use stainless wire with galvanished shackles, use galavanised wire and it will last. When I put shackles on my anchor, I tighten them up with an ajustable, then take a centre punch and punch the threads, between the eye and the pin, causing a burr, which will not allow the pin to come out in normal use, but allows it to be undone with a bit/lot of extra pressure with a big adjustable.
 
"Zinc passified" got me there. I googled it and found very erudite forums in which it appears the passivation is probably a chromate conversion coating of the zinc which greatly increases the resitance to corrosion. This leads to the question - Will this mean that another part of the chain (sic) will suffer due to the presence of dissimilar metals?

(When I mentioned stainless locking wire I was being very lax. I haven't even read the label on the spool. )
 
"For one thing, never use stainless wire with galvanished shackles, use galavanised wire and it will last"
That makes sense - but can you use Monel wire ?? - without anything corroding ?
 
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