Tightening of mooring shackle

When I was responsible for club moorings I moused the shackles with galvanised steel wire and welded both ends of the pin to the bow. One year I used zip ties as well, but they all fell off; I have no idea where the ties came from so they might have been cheapy ones. It didn't seem to make any difference whether I used galvanised shackles or not, so I moved to all ungalvanised as they didn't need the zinc removed before welding.
 
I gave mine a little nip with the spanner, just a little more than by hand and then used some S/S wire.

I think i'm going to have one of each type of strop this year on the lake (similar to Lakesailor's photo). I've seen a few posts by LS now and i think its a good idea. I already have a new standard strop sold by Maiden.

When replacing my new strop i looked at the shackle on my 2nd strop, it seemed "ok" so i made a note to replace it this coming year. I noticed a little bit of thinning in the metal. When i went to get the boat out in November, she was only held on with one strop.

Lesson learned.
 
For mousing wire I use the core of a Morse 33C cable. Seems awful tough to me, and no degradation yet. Seen low quality shackles where the thread disappeared altogether. I get ex WD shackles from a local salvage store, very high quality.
 
The strops with pipe already on them are lethal.
This one was bought by the guy I sold Feckless to in June. The inside edge of the pipe at the riser end of the strop has chafed through the nylon.

chafedline.jpg
 
Lakesailor said:
That piece of fence wire has been on the previous shackle for 2 years and is now on that new one. I only replaced ithe shackle because of pin wear. Believe me, the force needed to bend that wire is enormous. A simple pin unwinding could not even stress that wire.
I've used monel mousing wire and found any friction busts it off in no time.

As for your point about direction. That pin could only unwind about 1/5th of a turn. It would need to unwind possibly 7 turns to fall out.

The other shackle was fitted by the moorings contractor and has the threads peened. That was fitted 2 years ago.

However, when this poor weather is over I will be adding more fence wire to the other shackles as belt and braces.
Click to expand...

Lakesailor,

I was only going by what I was taught as an apprentice, wirelocking - inc direction against 'undo' rotation- is a major thing with aeroplanes, getting it wrong more than once would probably mean the sack - but the function remains the same on a boat shackle which one is almost as keen to stay in place.

One or two strands of monel would be possible to override with a spanner, but on moorings I do about 6 turns, wirelocked, and then the same again - ie 2 goes each shackle; not had a problem yet in 34 years - touchwood !

I take the point about your bit of wire being strong, just personally if using that would like it a bit longer & more secure; and I don't like cable ties for mousing, either !
 
You get 2 types of shackles.

D ring like you see in most chandlery's with just a pin which you would grease up to protect the thread, screw in hand tight and then back off half a turn. Then secure using stainless lock wire or an indutrial zip tie. These are only designed to be loaded in one way. On the pin and the top of the curved section.

The other and for this purpose probably better solution would be a Bow (4 part) shackle. This can be loaded in any direction and can be found in weights from 1/2ton to > 200 ton. These have a bolt which goes through the shackle, screw the nut onto the greased up thread, back off half a turn and secure in place with the correct sized split pin. We use these offshore and i have never seen one fail in use. And ours get treated worse than anywhere else.

On another note, if you use a D shackle, over tightened and moused and therefore misshapen, if your insurance company cottons on you won't have a claim as you used them contrary to manufacturers instructions.

When it comes to shackles etc, it may not be cheaper but UK or US made ar in our experience the most durable.

Niall
 
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