Seizing wire: cheaper alternative to Monel?

We've used ss wire for mousing anchor shackles for many years now without a problem. That with both ss shackles (which we have used exclusively for quite a number of years) and galvanized ones before that.

As Vyv says it does work harden and that needs to be kept in mind if reusing the same piece ofwire again but our experience is that if it is going to fail it does so when retwisting it and failing in the twist part, not in the cat part (the cat part being the part that does the mousing) so one has fair warning of the problem.

Someone claimed that the ss will affect the galvanizing on the shackle. That is not the case as the mass of the galvanizing is far, far greater than the mass of the ss in the wire (second law of corrosion, commonly seen applied to fastener selection). In fact we have never seen any such issue even between ss shackles and galv anchor chain or the anchor (but we use good quality chain not the rubbish often seen used).

If you are near a big fishing port and go into the workshop of a company doing all the wire rope and similar rigging work for the fleet and ask, they may just give you a lifetimes supply of single strand ss wire free (that from my experience).
 
dmmbruce said:
Has anyone ever known an un-moused shackle shake loose?

There are lots of anecdotal stories of it. Some may be true.

But has anyone actually had it happen to them?

I haven't.

Mike
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Shackles have to be secured, period. Especially ones used for moorings. I favour Loctite.
 
savageseadog said:
Shackles have to be secured, period. Especially ones used for moorings. I favour Loctite.
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I know a few folk who use cable ties (ty-wraps) to mouse shackles with on deep sea moorings, but I've never been convinced. Either a shackle is going to try and undo itself or it isn't. If not, then fairy snot will keep it done up. :D

If it does, then anything that you can break by unwinding the pin with a shifter is probably not strong enough. There's a certain amount of mechanical advantage in a screw thread, and whatever is undoing the shackle will use that. Surface moorings are probably worse than anything else in that respect.

The advantage of multi strand is, once you've wound your board-of-trade figure-of eights around it, you can bash it down to remove any nasty sharp bits that will gash your hands when you next handle it. If you're mousing rigging or moorings, you should really inspect them at least once every 12 months.
 
jerrytug said:
Hello,is this a bright idea?... I was going to buy some monel seizing wire, for securing the galvanized shackes connecting my galvanised chain to my galvanised anchor. It`s £10 for a tiny roll in the chandlers, and similar on the internet. However,I can buy 700g (about 1.5 lbs!) of 0.8mm stainless steel MIG welding wire for twice that price,which is a lot of seizing. Is there any reason I shouldn`t use it, on galvanised shackes under water? Or indeed for mousing 316 stainless rigging screws etc?
I was thing of some sort of disastrous potential for galvanic corrosion etc. Please some expert tell us it`s safe! Thanks a lot Jerry.
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You will be fine using MIG wire provided you get a decent grade - 316, 317, and not 308 or 304. I've been using it without problems for the last 30 years since I worked for a firm that made the stuff. Mind you, I have never used it in a situation where I fasten something and then leave it under water for several years
 
Welcome to the forum, where and what do you sail? I generally potter around on an old gaff cutter, looking for trouble.
 
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I dont know what the guy who fixed my stern riser chain to the mooring buoy (2 years ago) used for seizing, but the riser chain is now laying on the seabed, and my boat on a borrowed mooring, the monel wire I used for the fore mooring seizing is still there and still holding. So often I see totally rusted up seized shackles, but every now and again I see one that has lost its pin, I cant stress the importance of seizing wire enough, but don't twist it over and over and over, it will cause damage to the wire that you cant see.
 
ChrissieTwo said:
I dont know what the guy who fixed my stern riser chain to the mooring buoy (2 years ago) used for seizing, but the riser chain is now laying on the seabed, and my boat on a borrowed mooring, the monel wire I used for the fore mooring seizing is still there and still holding. So often I see totally rusted up seized shackles, but every now and again I see one that has lost its pin, I cant stress the importance of seizing wire enough, but don't twist it over and over and over, it will cause damage to the wire that you cant see.
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Unfortunately seizing is not always the answer. This shackle failed in less than one season and the boat went ashore despite having seizing wire, still evident. There are some very poor shackles around that rust far too readily.

 
me, found my stern mooring buoy detached from the riser the other week,
and as a surveyor, yes, I occasionally see a shackle that has started working itself loose
 
For a fair number of years I worked in technical sales in sheffield at a plant that made stainless steel wire including that for welding as well as for jet engines, dental impants etc. In my garage I have a coil of 0.8mm mig wire that I have been using for seizing for the past 30 years. Both above surface and below surface where it was used on the shackles that connected my ground anchors to the mooring lines. Its currently in use on my rigging. No problems though as a matter of good practice I inspected my below surface shackles every 12 months before the boat was launched. Never any visible corrosion.

But here is the hard bit - after that long I cant remember the grade of stainless. It wont have been 304 - I dont ever remember mig wire in that grade and it wouldnt be suitable anyway. Could well have been 310, maybe 316 or 347. If I was buying some more i would buy the most highly alloyed austenitic grade I could. And dont re-use bits, though I admit that I have done so myself.

The problem with stainless below water occurs when there is both surface abrasion and stagnant air free water. The abrasion removes the oxide coat than makes stainless stainless. The lack of air prevents it rebuilding that coat and it then corrodes just as fast as mild steel. So, for example I would never use stainless below water buried in a wood hull or GRP fixings. I once removed the stainless skeg bolts on my Prout cat - they had been there 8 or 9 years and were 10mm shaft diameter. Cant remember the precise numbers but it was something like 3 bolts came out moth eaten but in one piece whilst the other 9 came out in two pieces having corroded right through.

So to summarise, yes mig wire will make decent seizing wire but if you use it below the water surface you need to think carefully about where, and check it regularly.
 
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