Another chain question

[Ian_Edwards]

Eynhallow has 80m of 10mm galvanized chain +30m of nylon rode, I suspect that it is grade 30, but don't know, it was on the boat when I bought it
The boat is 14m (46ft) and fully loaded is about 16 tons.
The boat is a Southerly, with a lifting keel, which is very narrow, the exact opposite of a long keel boat, as a result she shear quite a lot on anchor in a gale, so snatch loads are probably higher than many boats of a similar length and displacement. Although I do use a relatively long nylon bridal to reduce the snatch load.
I anchor for around 100 nights per year, NW Scotland, generally in mud/clay/sand, I occasionally hear the chain rumble of stone during the night as the wind and/or tide change direction.
The chain is needs to be replaced, or re-galvanizing.
The chain has been end of ended, and is not yet really rusty, but not far off, if I was replacing it I would use it another year.
The chain has been re galvanized once already in February 2017, by Highland Galvanizers, who did a good job, just a couple of links "welded" together by zinc, which cleared the first time it was used.
Current quote to re-galvanize it £500- £600 +VAT, so say around £700.
GS Products are selling Grade 30, 10mm Galvanized short link chain, DIN 766, breaking load 5000kg for £11.11 inc VAT /m, or £888.80 for 80m.
There are other sites selling grade 30 for around that price, eg Force 4 at £10.95
Jimmy Green is selling MF Grade 40 for £14.00 per m, I think inc VAT, or £1,120.

So it's marginally cheaper to get the chain re-galvanized.
I might be tempted to go for 100m of new chain, and remove the 30m of nylon, mainly because the splice between the chain and the nylon doesn't always go through the windlass smoothly. The gypsy is on a vertical shaft, and the rode has to go through a 45 deg bend in the horizontal plane and the 90 deg down into the chain locker. I also thinking that an extra 20m of chain is roughly equivalent to 30m of nylon.
I'm not sure that it's worth going for grade 40?
And I'm tempted to go for re-galvanizing again.
Any comments?

 

[vyv_cox]

My experience is that regalvanised chain lasts twice as long as new. I believe the thickness of zinc on new chain is supposedly 70 microns but when BE Wedge regalvanised mine they claimed a minimum of 90 microns but said it would probably be 100. If your galvaniser uses a batch process, which I think they do, the thickness may well be more again.

Chinese chain seems to be generally sold as Grade 30 but tests to Grade 40. Grade 30 steel is dead mild, no alloying elements at all, whereas Grade 40 has some manganese and others. The latter is widely available in China, used throughout the construction and engineering industries, whereas dead mild would cost money to refine.

Where do you need more than 80 metres? I have cruised widely from northern Scotland to Greece and carry 64 metres. I have only ever run all of it out during stern-to berthing, mostly by accident.

 

[geem]

My experience is that regalvanised chain lasts twice as long as new. I believe the thickness of zinc on new chain is supposedly 70 microns but when BE Wedge regalvanised mine they claimed a minimum of 90 microns but said it would probably be 100. If your galvaniser uses a batch process, which I think they do, the thickness may well be more again.

Chinese chain seems to be generally sold as Grade 30 but tests to Grade 40. Grade 30 steel is dead mild, no alloying elements at all, whereas Grade 40 has some manganese and others. The latter is widely available in China, used throughout the construction and engineering industries, whereas dead mild would cost money to refine.

Where do you need more than 80 metres? I have cruised widely from northern Scotland to Greece and carry 64 metres. I have only ever run all of it out during stern-to berthing, mostly by accident.

We have 60m of chain plus 50m of anchorplait. Used the anchorpliat about 3 times in 10 years.

 

[vyv_cox]

We have 60m of chain plus 50m of anchorplait. Used the anchorpliat about 3 times in 10 years.

I set my kedge up with 5 metres of chain and 50.metres of Anchorplait. They are attached together with a shackle and eye splice with a steel thimble so I could add it to the bower chain if I needed to. That was in 1999 and I never have.

 

[[2574]]

Do have a look at swapping for 8mm grade 70. Jimmy Green supplies in 80m or 10m lengths. I swapped out to 8mm mainly to extend the chain length but reduce weight in the chain locker.

 

[Ian_Edwards]

Thanks VYV,
That confirms my view, the galvanizing Highland Galvanizers applied 2017 seemed to be very thick, and has worn well.
The maximum chain I've used is 70m, anchored in 20m, at HW, with 2m from water level to bow roller, in Loch Duich (up by Ratagan, near the head) in 50knots + of very squally winds. The Loch is deep, 100m + and very steeps sided, 22m x 3 =66m.
I regularly use 40m+ chain, anchoring in the 10m to 15m range.
I also like to have a little in reserve, just in case.?

 

[Martin_J]

Nobody ever seems to mention the Lofrans grade 40 chain that is sold at Marine Super Store. Their Lofrans grade 40 10mm chain is £10.95/m. (Cheaper than the other suppliers mentioned above).

Is this the same standard as other grade 40 Chinese chain is supposed to be?

 

[thinwater]

Eynhallow has 80m of 10mm galvanized chain +30m of nylon rode, I suspect that it is grade 30, but don't know, it was on the boat when I bought it
The boat is 14m (46ft) and fully loaded is about 16 tons.
The boat is a Southerly, with a lifting keel, which is very narrow, the exact opposite of a long keel boat, as a result she shear quite a lot on anchor in a gale, so snatch loads are probably higher than many boats of a similar length and displacement. Although I do use a relatively long nylon bridal to reduce the snatch load.
I anchor for around 100 nights per year, NW Scotland, generally in mud/clay/sand, I occasionally hear the chain rumble of stone during the night as the wind and/or tide change direction.
The chain is needs to be replaced, or re-galvanizing.
The chain has been end of ended, and is not yet really rusty, but not far off, if I was replacing it I would use it another year.
The chain has been re galvanized once already in February 2017, by Highland Galvanizers, who did a good job, just a couple of links "welded" together by zinc, which cleared the first time it was used.
Current quote to re-galvanize it £500- £600 +VAT, so say around £700.
GS Products are selling Grade 30, 10mm Galvanized short link chain, DIN 766, breaking load 5000kg for £11.11 inc VAT /m, or £888.80 for 80m.
There are other sites selling grade 30 for around that price, eg Force 4 at £10.95
Jimmy Green is selling MF Grade 40 for £14.00 per m, I think inc VAT, or £1,120.

So it's marginally cheaper to get the chain re-galvanized.
I might be tempted to go for 100m of new chain, and remove the 30m of nylon, mainly because the splice between the chain and the nylon doesn't always go through the windlass smoothly. The gypsy is on a vertical shaft, and the rode has to go through a 45 deg bend in the horizontal plane and the 90 deg down into the chain locker. I also thinking that an extra 20m of chain is roughly equivalent to 30m of nylon.
I'm not sure that it's worth going for grade 40?
And I'm tempted to go for re-galvanizing again.
Any comments?

For the moment, let's go from talking about chain to solving the root of the problem. Sheering. Chain is just a Bandaide and will fail to control sheering when the wind is strong enough to lift the chain. The job of the anchor is to hold a steady pull, not a romping side to side jerking. That is the sailors job. And I assure you it is possible; I have tested methods on some wild boats.

• The keel needs to stay down when anchored. (Not sure if you lift it) Lifting the keel moves the COE aft and will make it yaw like it's rabid. Lifting the rudder will also help when possible.
• Use a riding sail. Single luff sails are not effective in serious cases, but the twin luff Fin Delta from Banner Bay will do it. Very effective.
• Add a drogue to the rode about 20 feet forward of the bow, hanging just below the water, no pendant. About 3' in diameter should do. This will slow the yawing motion and also reduce pitching. It does not need to be an expensive storm drogue. Weight the bottom ~ 1-2 pounds so that it hangs down when the boat is not moving, ready for the next cycle.

You probably do not need to do all of these. But try them. Yawing can reduce anchor security by as much as 80% by loosening the soil. You've got to stop the yawing if you are serious about staying put in a blow.

 

[Ian_Edwards]

Nobody ever seems to mention the Lofrans grade 40 chain that is sold at Marine Super Store. Their Lofrans grade 40 10mm chain is £10.95/m. (Cheaper than the other suppliers mentioned above).

This sound interesting, but when I enter 80m, I get the following message:

"Please note: Chain lengths over 20m, or 10mm chain over 10m, cannot be delivered by carrier due to the weight. You can either Click & Collect or reduce the total quantity to a shippable length."

Since I live in NE Scotland, approximately a 1,200 mile round trip, it's not a practical option!

 

[Martin_J]

This sound interesting, but when I enter 80m, I get the following message:

"Please note: Chain lengths over 20m, or 10mm chain over 10m, cannot be delivered by carrier due to the weight. You can either Click & Collect or reduce the total quantity to a shippable length."

Since I live in NE Scotland, approximately a 1,200 mile round trip, it's not a practical option!

I understand, although I do friends on the South Coast who do make trips in that direction. It might be rather a large car load though

I was just intrigued why in all these chain threads, Chinese chain is often mentioned but never Lofrans... Did I do wrong buying lofrans locally rather than a.n.other Chinese brand?

Marine Super Store so seen to get through lots of chain. The number of metres they have available varies daily.

 

[Neeves]

In your costing for regalvanising with Highland Galvanisers have you included delivery costs both ways. As mentioned in the thread delivery does become important with large chain and long lengths.

Lofrans call it 'their' chain and distributors here call it Lofran's own chain - Lofrans, and nobody else, would ever install a new chain line - chain comes from China (except for the Italian chain from MF). Lofrans I am sure will test what they sell - they will be reliable - they cannot afford to be slack.

Most of the big importers will be the same as Lofrans, buy from a single source and test. Find a source of cheap chain, noticeably cheap - and be wary. There are hundreds of chain makers in China. The reputable importers will deal with a single source.

Jonathan

Eynhallow has 80m of 10mm galvanized chain +30m of nylon rode, I suspect that it is grade 30, but don't know, it was on the boat when I bought it
The boat is 14m (46ft) and fully loaded is about 16 tons.
The boat is a Southerly, with a lifting keel, which is very narrow, the exact opposite of a long keel boat, as a result she shear quite a lot on anchor in a gale, so snatch loads are probably higher than many boats of a similar length and displacement. Although I do use a relatively long nylon bridal to reduce the snatch load.
I anchor for around 100 nights per year, NW Scotland, generally in mud/clay/sand, I occasionally hear the chain rumble of stone during the night as the wind and/or tide change direction.
The chain is needs to be replaced, or re-galvanizing.
The chain has been end of ended, and is not yet really rusty, but not far off, if I was replacing it I would use it another year.
The chain has been re galvanized once already in February 2017, by Highland Galvanizers, who did a good job, just a couple of links "welded" together by zinc, which cleared the first time it was used.
Current quote to re-galvanize it £500- £600 +VAT, so say around £700.
GS Products are selling Grade 30, 10mm Galvanized short link chain, DIN 766, breaking load 5000kg for £11.11 inc VAT /m, or £888.80 for 80m.
There are other sites selling grade 30 for around that price, eg Force 4 at £10.95
Jimmy Green is selling MF Grade 40 for £14.00 per m, I think inc VAT, or £1,120.

So it's marginally cheaper to get the chain re-galvanized.
I might be tempted to go for 100m of new chain, and remove the 30m of nylon, mainly because the splice between the chain and the nylon doesn't always go through the windlass smoothly. The gypsy is on a vertical shaft, and the rode has to go through a 45 deg bend in the horizontal plane and the 90 deg down into the chain locker. I also thinking that an extra 20m of chain is roughly equivalent to 30m of nylon.
I'm not sure that it's worth going for grade 40?
And I'm tempted to go for re-galvanizing again.
Any comments?

Veering is caused by the yacht characteristics, as Thinwater addresses, and because the wind is veering. Stand at an airport on a windy day and watch aircraft landing . They seldom come into land in a straight line - they wriggle all over the place - corrected (I assume) by the autopilot. The wind in many anchorages is no different - the average direction might be constant but the gusts come in different directions. You can quell veers caused b y fluctuations in wind both by using a bridle and/or anchoring in a 'V' or fork. Following Thinwater's sound recommendations will make little difference if its the wind causing the veers - not the yacht characteristics.

In any event you want the yacht to be as stable as possible a reduce lateral pulls on the anchor.

Define the variation in wind direction and deploy your first anchor to near one extreme of direction and the other anchor for near the other extreme. As each anchor comes into play it will simply resist one direction and have no or less lateral tension.

You will need two snubbers, one for each anchor or one rode need have a snubbing effect.

Choosing a 'sheltered' anchorage does not always work as bullets pass down valleys or through trees when winds are strong - that you simply do not notice in light winds.

Jonathan

 

[thinwater]

In your costing for regalvanising with Highland Galvanisers have you included delivery costs both ways. As mentioned in the thread delivery does become important with large chain and long lengths.

Lofrans call it 'their' chain and distributors here call it Lofran's own chain - Lofrans, and nobody else, would ever install a new chain line - chain comes from China (except for the Italian chain from MF). Lofrans I am sure will test what they sell - they will be reliable - they cannot afford to be slack.

Most of the big importers will be the same as Lofrans, buy from a single source and test. Find a source of cheap chain, noticeably cheap - and be wary. There are hundreds of chain makers in China. The reputable importers will deal with a single source.

Jonathan


Veering is caused by the yacht characteristics, as Thinwater addresses, and because the wind is veering. Stand at an airport on a windy day and watch aircraft landing . They seldom come into land in a straight line - they wriggle all over the place - corrected (I assume) by the autopilot. The wind in many anchorages is no different - the average direction might be constant but the gusts come in different directions. You can quell veers caused b y fluctuations in wind both by using a bridle and/or anchoring in a 'V' or fork. Following Thinwater's sound recommendations will make little difference if its the wind causing the veers - not the yacht characteristics.

In any event you want the yacht to be as stable as possible a reduce lateral pulls on the anchor.

Define the variation in wind direction and deploy your first anchor to near one extreme of direction and the other anchor for near the other extreme. As each anchor comes into play it will simply resist one direction and have no or less lateral tension.

You will need two snubbers, one for each anchor or one rode need have a snubbing effect.

Choosing a 'sheltered' anchorage does not always work as bullets pass down valleys or through trees when winds are strong - that you simply do not notice in light winds.

Jonathan

^^ And what he said. If I expect big variations and a gale I set two anchors in a staggered V. It has always worked well.

 

[Poey50]

^^ And what he said. If I expect big variations and a gale I set two anchors in a staggered V. It has always worked well.

By "staggered V" do you mean that the rodes are not of equal length?

 

[Ian_Edwards]

I don't see a problem with delivery, 10mm chain has a weight of about 2.3kg/m, 80m weighs 184kg.
Last time I put the chain on a 1/2 pallet and got the yard fork lift the put it in the back of my Subaru Outback estate car, maximum load 450kg. The load was placed as far forward as practical (back seats down), I drove it the the Galvanizers, it was off loaded with a fork lift.
I'll do the same with my current car, maximum load 500kg.
500kg is the weight of 5 large men! Although they may struggle to all get in the car.

 

[RivalRedwing]

give Eye Marine a call, they specialise in chain and all things related; their current web site is thin on content but their prices can be considerably lower than chandleries for very good quality products
Home

 

[geem]

By "staggered V" do you mean that the rodes are not of equal length?

We have also used two anchors when a blow was known to be coming from a single direction. Main anchor set on chain as normal. Second anchor set on all rope rode but longer than the chain. This avoids anchor and chain clashing with anchor and rope if for some reason one was to drag. We found that laying to the rope anchor combo as much as possible when we first set, loaded up the rope so it stretched then brought the chain under tension. This ensured that the load was shared more evenly between anchors. There is no benefit if you don't have a lot of tension in the rope set anchor. You might need to haul more rope in as conditions change so running it through a fairlead to a winch can be useful for adjustment back at the cockpit

 

[thinwater]

By "staggered V" do you mean that the rodes are not of equal length?

Yes. One of the reasons was given by geem; if the lengths are different the anchors are less likely to foul.

However, if the wind shifts far ( a front passage), there is no V that will continue to share the load. Eventually the load is on one anchor. The other reason for different length rodes is so that the anchor that is more likely to drag (and should be the one that is more drag-stable and able to rotate to face the new direction) can be placed on the shorter rode, and the one that is higher holding (a Fortress, for example) ca be on the longer rode and not move. In this way they continue to share the load without fouling.

I connect the rodes for three reasons:
a. The primary does not have to drag as far to begin sharing the load again.
b. Simpler for a cat using a bridle.
c. They will not twist-up if the tide swings like two separate rodes will. Always easy to up-anchor. This is big one in tidal areas and with front passages.

I have tested this set up and reasoning on soft mud with load cells many times. And in real storms. For very soft mud, where dragging is most likely for me, it works. This is my most common set-up (lengths are for relatively shallow water).

 

[Boathook]

This sound interesting, but when I enter 80m, I get the following message:

"Please note: Chain lengths over 20m, or 10mm chain over 10m, cannot be delivered by carrier due to the weight. You can either Click & Collect or reduce the total quantity to a shippable length."

Since I live in NE Scotland, approximately a 1,200 mile round trip, it's not a practical option!

Give EYE marine a call. My 60m of 8mm chain came on a small pallet on a small lorry with a tail lift.

 

[Poey50]

Yes. One of the reasons was given by geem; if the lengths are different the anchors are less likely to foul.

However, if the wind shifts far ( a front passage), there is no V that will continue to share the load. Eventually the load is on one anchor. The other reason for different length rodes is so that the anchor that is more likely to drag (and should be the one that is more drag-stable and able to rotate to face the new direction) can be placed on the shorter rode, and the one that is higher holding (a Fortress, for example) ca be on the longer rode and not move. In this way they continue to share the load without fouling.

I connect the rodes for three reasons:
a. The primary does not have to drag as far to begin sharing the load again.
b. Simpler for a cat using a bridle.
c. They will not twist-up if the tide swings like two separate rodes will. Always easy to up-anchor. This is big one in tidal areas and with front passages.

I have tested this set up and reasoning on soft mud with load cells many times. And in real storms. For very soft mud, where dragging is most likely for me, it works. This is my most common set-up (lengths are for relatively shallow water).

That's interesting, thanks. I had assumed that both rodes are led back to the boat. I can't quite get my head round the procedure for laying them, if you are willing to elaborate.

 

[thinwater]

That's interesting, thanks. I had assumed that both rodes are led back to the boat. I can't quite get my head round the procedure for laying them, if you are willing to elaborate.

Easy. Two ways.
1. Set the first anchor at short scope. Lay the second from a tender, link the rodes near the boat, and then ease back.
2. Set the first anchor. Motor over to the spot for the second and lower it, with a removable extension long enough to reach back to the boat at full scope. Set both. Then shorten up, joint the rodes, remove the extension, and ease back.

It takes as long to explain as it does to do. I have done this MANY times when using my boat as a test platfor for anchor testing (I would drag anchors toward the transom, using the twin anchors to hold the boat and pulling with winches and purchase.