At risk of starting an anchor thread... a windlass and chain question...

Kukri

Kukri

Well-Known Member
Joined
23 Jul 2008
Messages
15,562
Location
East coast UK. Mostly. Sometimes the Philippines
Visit site
New to me boat is an Ohlson 38, recently bought, and I have a little list of winter jobs..

Home waters are the Thames estuary

The windlass is an SL 555 / Seatiger with a 10mm rope/chain gypsy. The chain is worn out and the windlass needs an overhaul, so if I am going to make changes, now is the time.

My personal habit with the last boat, a gaff cutter of the same size but a good deal more displacement and windage, with a Reids of Paisley windlass that would have suited a young battleship, was to anchor using a 45lbs CQR and a fairly short scope of 12mm chain, and if things got exciting, which they seldom did, to veer more chain and drop an angel down it. Her displacement was such that 100 metres of 12mm chain didn't really bother her much, but the new lady, whilst a good deal heavier than an AWB, is more delicate, and the received wisdom is to get the weight amidships if you can.

Option 1: overhaul the windlass and buy some 10mm chain

Option 2: ditto but swap the gypsy and go for 12mm chain

I'm not asking about anchors as I have used CQRs for forty-five years and I am stuck in my ways - besides, it stows easily in the fairlead...
 
Minn said:
New to me boat is an Ohlson 38, recently bought, and I have a little list of winter jobs..

Home waters are the Thames estuary

The windlass is an SL 555 / Seatiger with a 10mm rope/chain gypsy. The chain is worn out and the windlass needs an overhaul, so if I am going to make changes, now is the time.

My personal habit with the last boat, a gaff cutter of the same size but a good deal more displacement and windage, with a Reids of Paisley windlass that would have suited a young battleship, was to anchor using a 45lbs CQR and a fairly short scope of 12mm chain, and if things got exciting, which they seldom did, to veer more chain and drop an angel down it. Her displacement was such that 100 metres of 12mm chain didn't really bother her much, but the new lady, whilst a good deal heavier than an AWB, is more delicate, and the received wisdom is to get the weight amidships if you can.

Option 1: overhaul the windlass and buy some 10mm chain

Option 2: ditto but swap the gypsy and go for 12mm chain

I'm not asking about anchors as I have used CQRs for forty-five years and I am stuck in my ways - besides, it stows easily in the fairlead...
Click to expand...

10mm chain will be satisfactory I never had a problem with it on a 7 tonne displacement boat and I also happily used a CQR:encouragement:
 
How much 10mm chain are you going to buy? 10mm is sufficeintly strong if the yacht really weighs 7t you could almost lift it with that chain.

And you mention getting the weight amidships - but its on the wish list - what's the plan? 10mm chain is 'quite' heavy.
 
Last edited:
100 metres of 10mm chain will weigh 230 kg

100 metres of 12mm chain will weight 380 kg

The boat's design displacement is 6.6 tonnes or 14,540lbs, with officially a 41% ballast ratio. In fact she sits nicely on her marks so the ex owner got his sums right, but he carried less chain than I propose to. Looking at it, I think he carried 30 metres

The chain locker is under the windlass and more or less exactly at the forward end of the waterline.

Old boat displaced 20,000 lbs on much the same dimensions.

There is a sizeable, very deep, bilge sump in the after section of the fin (the ballast is encapsulated) accessible by lifting a hatch in the cabin sole - that would make the "dream" chain locker, if one could find a way to get the chain to and from it! :rolleyes:

http://www.ohlson38.de/Ohlson 38 construction/Ohlson 38 Dimensions/Ohlson38.Dimensions.html
 
Last edited:
macd said:
Vyv Cox's website will reveal all: https://coxengineering.sharepoint.com/Pages/Chaindefinitions.aspx
But why not take the gypsy along when you buy the new stuff, then you'll know for sure.
Click to expand...

Thanks for the link; very informative.

Yes; I was told to bring the gypsy along with me when buying.

As regards strength, the only way a chain will break is if the boat is snatching on it and brings it up taut, which, "by definition" should never happen if one uses an angel.
 
Last edited:
Minn said:
Thanks for the link; very informative.

Yes; I was told to bring the gypsy along with me when buying.

As regards strength, the only way a chain will break is if the boat is snatching on it and brings it up taut, which, "by definition" should never happen if one uses an angel.
Click to expand...

Alas the maths don't bear that out - see multiple past threads - in any moderate wind (so long before it becomes strong) a 10 or 12mm chain will have so little curve left there is nothing left to go elastic, and the angel will weigh a lot less and will only be in the right place by coincidence.

So that's why the general consensus (although not accepted by all) is that the ideal would be the strongest holding anchor (whatever it's weight) combined with an infinitely strong piano wire as weight doesn't matter there either as soon as a continuous load. Hence the thread about stronger 8mm which is convincing a lot of us with 40+ foot boats but only because we can't quite yet be convinced that we can replace our 10mm or 12mm chain with superstrong 6mm.
 
Last edited:
There are two types of 10 mm chain and they vary in length and I think pitch. If you get the wrong one it will jam in the gypsy

the two types are DIN766 and ISO. One has a 28mm pitch and the other has a 30mm pitch.

Good luck!
 
10mm chain - and 100m of it is way OTT for the displacement of the boat you have. To reduce weight without compromising strength you could reduce size to 8mm (assuming you can get a new gypsy) and length to 60m plus 40m rope and invest the money saved in an anchor that will hold better. Anchoring (like most things yottie) has moved on a long way since CQR and lots of heavy chain were the norm. If you can spare the time there is plenty of evidence that what I (and others) suggest is superior - much of it discussed at great length in the regular threads on the subject here.
 
Minn said:
...As regards strength, the only way a chain will break is if the boat is snatching on it and brings it up taut, which, "by definition" should never happen if one uses an angel.
Click to expand...

It'd work better with a nice stretchy snubber between chain and boat, some say 10m though mines about 2m once its on a cleat
 
Tranona said:
. . . .reduce size to 8mm (assuming you can get a new gypsy) . . .
Click to expand...

I think you'll struggle to find an 8mm gypsy for a SL555. They are very rare and in great demand as the chain size for thirty-seomthing foot boats (the remaining refuge of the manual windlass), has dropped from 10mm to 8 over the years. So everyone with a 10mm gypsy would love an 8mm one in order to half the weight of their chain. It's time the guy at SL Spares had the casting pattern re-carved.
 
Motor_Sailor said:
I think you'll struggle to find an 8mm gypsy for a SL555. They are very rare and in great demand as the chain size for thirty-seomthing foot boats (the remaining refuge of the manual windlass), has dropped from 10mm to 8 over the years. So everyone with a 10mm gypsy would love an 8mm one in order to half the weight of their chain. It's time the guy at SL Spares had the casting pattern re-carved.
Click to expand...

Then perhaps it is time to consider a new windlass. A lofrans Cayman 88 would be just the job in this application.
 
A Lofrans Cayman 88 uses vast amounts of Amps, whereas the SL555, the finest anchor weighing equipment known to man, can run all day on half a Fray Bentos steak & kidney pie.
 
Looks like I started an anchor thread after all.

So I will just say a few words.

I anchor a lot. Often close to the edge of dredged channels, but sometimes in the open sea to wait a tide. I don't like to veer more chain than I need. I do use a nylon snubber. I also use an angel when I feel it is worth the bother. One very rarely needs 100 metres, but just occasionally one does.

I am a big fan of the modern type chain roller which has a flat surface with a square, chain sized trough cut in it to take the alternate links. And it should be made of plastic and of large (say 120mm) diameter. This takes a lot of the work out of getting the chain up, you ride quietly with no metal graunching on metal, and you don't need one of those problematical chain swivel things. Having done that you might as well fit a pawl to it, in the approved Claud Worth manner. And I would like someone to make a windlass that will mount on the mast and operate in the manner of a two speed sheet winch. But so far as I know, nobody does. If you have your windlass on the mast, you can have your chain locker more or less built into whatever bulkheads you have near the mast...
 
You must log in or register to reply here.

Other threads that may be of interest

mogmog2
Maxwell windlass 10 VW looks interesting (to a windlass noob)
2 3
Replies
59
Views
1K
mogmog2
mogmog2
Y
Quick Aries 1000 anchor windless noisy
Replies
0
Views
102
yotter
Y

Share this page

Top