Chain size help please.

[Elessar]

My chain was a little rusty last year but its suddenly gone now. I need to replace it.

Daft question time. I no idea what 10mm chain means. What is measured?

Can you tell from these pics? (which were taken today HOORAH!)

 

[Roberto]

10mm is the diameter of the wire; 10mm chain comes in two different standards, look here to check which is suitable for your windlass

Chain 10mm ISO DIN.pdf

 

[Plum]

The 10mm is the diameter of the steel rod from which each individual link is made from.

Www.solocoastalsailing.co.uk

 

[Elessar]

Helpful posts thanks guys. Shame the standard isn’t so helpful. What’s wrong with the size of the link as a standard!
So I’ll go back and measure 10 links.

edit that diagram does have the link size I’ve just realised. Looks like 28mm internal. Do you agree?

Thank you.

 

[Poignard]

I'm interested to see that you have a s/s shackle connecting the low-carbon steel galvanised chain.

When I had that arrangement I was surprised at how quickly the chain rusted. I had the chain re-galvanized and replaced the s/s shackle with an ordinary galvanized one sized with galvanized wire, and it has lasted much longer before beginning to rust.

 

[Elessar]

I'm interested to see that you have a s/s shackle connecting the low-carbon steel galvanised chain.

When I had that arrangement I was surprised at how quickly the chain rusted. I had the chain re-galvanized and replaced the s/s shackle with an ordinary galvanized one sized with galvanized wire, and it has lasted much longer before beginning to rust.

I didn’t know regalvanising was a thing.
Any contacts for that? I presume it saved money?
Thanks for the tip on the shackle I hadn’t thought of that.

 

[RichardS]

Helpful posts thanks guys. Shame the standard isn’t so helpful. What’s wrong with the size of the link as a standard!
So I’ll go back and measure 10 links.

edit that diagram does have the link size I’ve just realised. Looks like 28mm internal. Do you agree?

Thank you.

From memory, 10mm chain is either 28mm or 30mm internal. Yours is presumably the former.

Richard

 

[Poignard]

I didn’t know regalvanising was a thing.
Any contacts for that? I presume it saved money?
Thanks for the tip on the shackle I hadn’t thought of that.

'

Years ago someone here (RowGear I think it was) organised for a few of us to deliver our chains to his house and he got them all done as a job lot somewhere in the Midlands. I think the whole operation put him to a lot of trouble and he made no money out of it so I doubt he'd be keen to repeat the process!

But a recent thread here has shown that finding someone to re-galvanise chain seems now almost impossible in England, so I don't know what to suggest.

By the way, when I posted before about my experience with the s/s anchor shackle it was ridiculed by one of the forum pundits as impossible.

 

[Plum]

In over 30 years I have never had a problem with using stainless shackles on galvanised chain.

www.solocoastalsailing.co.uk

 

[Catalina36]

I'm interested to see that you have a s/s shackle connecting the low-carbon steel galvanised chain.

When I had that arrangement I was surprised at how quickly the chain rusted. I had the chain re-galvanized and replaced the s/s shackle with an ordinary galvanized one sized with galvanized wire, and it has lasted much longer before beginning to rust.

Indeed so. What would be even more worrying would be for the stainless steel shackle to corrode out the eye of the anchor stock, rendering it useless. Far better to use a galvanised mild steel shackle and replace it every couple of years if necessary.
I always thoroughly rinse anchor, chain and windlass gypsy with fresh water after every deployment. I installed a deckwash pump to do it, using a changeover valve to use seawater brought in through a tee from the WC inlet to blast the mud off the anchor while it's hanging from the stemhead roller then switch to fresh water to rinse everything off in the chain locker. Sea water is the spirit of the devil.

 

[Plum]

I didn’t know regalvanising was a thing.
Any contacts for that? I presume it saved money?
Thanks for the tip on the shackle I hadn’t thought of that.

It is very hard to find places that will regalvanise chain. My recent experience was that if you have to pay to ship the chain to and from the place it was cheaper to buy new chain.

www.solocoastalsailing.co.uk

 

[Boathook]

If your chain is onto a windlass make sure that you get the correct calibrated chain for the windlass.

 

[Catalina36]

It is very hard to find places that will regalvanise chain. My recent experience was that if you have to pay to ship the chain to and from the place it was cheaper to buy new chain.

www.solocoastalsailing.co.uk

There's a helpful local steel fabricator in Portsmouth who will take in small loads to be added whenever a large job like a fire escape is sent for galvanising, thus avoiding the minimum charge which normally applies.

 

[Elessar]

There's a helpful local steel fabricator in Portsmouth who will take in small loads to be added whenever a large job like a fire escape is sent for galvanising, thus avoiding the minimum charge which normally applies.

Thanks. Got a name, link or number? Or just a clue??

 

[Rappey]

Wessex galvanisers, Eastleigh. Southampton

 

[LadyInBed]

I'm interested to see that you have a s/s shackle connecting the low-carbon steel galvanised chain.

I use a S/S shackle but I use a bit of plastic pipe over the pin as an insulator.

 

[Neeves]

Measuring chain is fraught with problems, especially old (worn) chain.

Take the windlass apart, its easy (check the manual) and the gypsy, chain wheel is in 2 parts. Look at each part and the chain size is engaved on one of the surfaces of the gypsy. If its 10mm it will also define if its an ISO or a DIN chain. There is an outside chance that if your boat is American then its imperial chain. An Imperial chain will NOT fit on a metric gyspsy. If its an imperial chain again it will be marked on the gypsy but note that imperial BBB, G3 aka G30, G4 aka G43 and G7 are all different sizes of link. There is some overlap and some gypsies are forgiving - just be careful. If you decide to go the 'new chain' route then take the gypsy to the chandler and match the chain to the gypsy by wrapping chain round the gypsy. If its a good chandler (they are few and far between) then the chandler will be able to mount your gypsy and run the length of chain you want to buy through your gypsy, proving to you the chain matches the gypsy.

You are a bit far away but the best galvaniser for chain now would be Highland Galvanisers based in Cumbernauld. The MD is a member here, does re-galvanise chain and being a yachtsmen is sympathetic to your needs. The issue is getting the chain to him and the idea of canvassing other members and getting a batch together will save money - but involves someone arranging it all. If your chain is painted the paint needs to be removed prior to galvanising - a wire brush on the end of a drill is one way - dragging the chain behind a car on a beach is less effort (but might need the wire brush as well).

If you cannot match chain to gypsy, or gypsy to chain - be aware - new gypsies are extortionate and you might then be better buying a new windlass rather than fitting a new gypsy to an old windlass. Looking at the picture of your boat 10mm does seem large - but maybe weight is not an issue and maybe also you have a mixed rode. If its an all chain rode 10mm chain is significantly heavy and you might need a wheelbarrow to move it from boat to someplace else.

Jonathan

 

[Poignard]

In over 30 years I have never had a problem with using stainless shackles on galvanised chain.

www.solocoastalsailing.co.uk

That is interesting, and seems to refute my experience.

All I can do is to describe what I experienced. I am not qualified to explain it.

However this, from the American Galvanizers Association might throw some light on it:

Stainless Steel in Contact with Galvanized Steel | American Galvanizers Association

 

[noelex]

The question of using a stainless steel shackle with galvanised chain and anchor comes up often.

Whenever two dissimilar metals are immersed in seawater there will be a galvanic effect. In this case it is the galvanised metal (especially the zinc coating) that will corrode. However, the effect is influenced by the ratio of the surface areas of the two metals.

In this case we have a very small amount of stainless steel with a very large amount of galvanised steel. So the extra corrosion on the galvanised steel is very slight. In most cases the effect is hard to detect or slight so that the few links of chain close to the shackle show some slight extra corrosion and need to be cut off every few years.

Occasionally a link or two of the chain close to the shackle can show more rapid corrosion. This is caused by poor electrical contact between the links of the chain. In the worst (theoretical) case the stainless steel shackle can be electrically connected to only one link of chain. This creates the situation where the surface area of the two metals is similar and so reasonably rapid corrosion of the last link or last few links can occur. However, it will not (or only imperceptibly) effect the whole length of chain.

So a stainless shackle is OK to use with galvanised chain and anchor providing you keep an eye on the last few links of chain.

Of greater concern is the quality of the shackle used to join the chain to the anchor. Make sure it is not a “no name” shackle, but is manufactured by a reputable brand and has a quoted load rating (SWL and UTS). Make sure the rating of the shackle exceeds the chain, you don’t want such a small component to be the weak link. It is actually worth having a shackle that considerably exceeds the chain rating. This is because with side loading the strength of the shackle will be much less than the published rating.

I use the largest galvanised Crosby 209A shackles that will fit. These are high strength galvanised shackles, but there are similar products from many companies.

 

[Catalina36]

Thanks. Got a name, link or number? Or just a clue??

He's down in the old Eastney Pumping Station building in Henderson Road at Eastney, can't recall the name. Google Earth street view shows Portsmouth Steel Fabrications I think. I don't know which galvaniser he sends it to and I've not taken chain in there, just other bits of steel for a trailer.