Help: My Anchor Chain Slips Over My Windlass Gypsy.

[YPSILANTI]

As part of a huge upgrade on my 53 ft. Royal Cape Catamaran, I installed a 1700W Falkon Lofrans windlass. I also fitted a new 13 mm / 0.500” / 1/2” /
chain. Upon ordering the windlass, I provided the factory inItaly with the chain specifications which is 13 mm / 1/2 " Din 766 short link galvanized grade 43 rated at 10.6 tons. They provided a gypsy with "teeth spacing" to match the chain specification. However, the chain does not grip onto the teeth of the gypsy properly. I am able to retrieve the chain and anchor but the chain slips briefly every few seconds, even before it takes up the weight & pressure of the anchor. I've engaged with the factory, with Lalizas who is the importer into South Africa and with the chain supplier. I've had engineers assessing the situation. I've modified the chain locker to increase the chain fall into the chain locker. The chain supplier say that the gypsy is not configured to match the chain. They advise that the chain is not a calibrated chain and so the links differ slightly. That surprises me as I've never heard of this issue before and nor has the chain supplier. The windlass manufacturer says that the chain is not calibrated. I've grappled with this issue for over a year and am uncertain as to where the problem definitely is. I'm being pushed from pillar to post. I'm absolutely perplexed. I will appreciate informed comments as to where the real problem is. Thank you for your anticipated replies.

[CarlF]

What brand of chain? A lot of Asian made chain isn’t made precisely enough to work on a windlass. I’d find out from Loframs which brands of 1/2” chain has worked well and buy one of those.

[GordMay]

Sometimes, horizontal windlasses require shimming to a height, where the chain runs, at least, parallel to the deck, in order to achieve a sufficient wrap, on the gypsy.

It’s always wise to supply [the windlass manufacturer] a short [12"] sample length, of your proposed anchor chain, to ensure a matching gypsy.

I believe that the DIN 766 standard is for calibrated, and tested chains.

The combination of wire diameter, outside link width, and most importantly the chain pitch [inside link length] must be consistent [calibrated within an allowed tolerance, or deviation] throughout the length of the chain, to ensure the best fit in the gypsy.
I don’t know how one could make a gypsy work consistently, with an “uncalibrated” chain.

Understanding DIN 766 Chain Specifications
➥ https://www.toponechain.com/new/din-...fications.html

[meirriba]

I am rather inclined to believe that the problem is with your chain.
You wrote in your post that you have ordered a 12mm/0.5" DIN 766 chain.
DIN is a milimetric standard. Not Imperial.
12mm DIN chain has +-3mm allowed external size difference and +6mm to - 3mm internal.
0.5" is not DIN standard and is 12.7mm when exact.
It seems to me that these possible numbers led to inadequate chain.
Moreover if the chain was not calibrated, you may have variations in size between links.
Try to use a caliber tool and actually check a meter or two if your chain links for internal and external sizes to find out if I am correct.

[Dockhead]

Originally Posted by meirriba

I am rather inclined to believe that the problem is with your chain.
You wrote in your post that you have ordered a 12mm/0.5" DIN 766 chain.
DIN is a milimetric standard. Not Imperial.
12mm DIN chain has +-3mm allowed external size difference and +6mm to - 3mm internal.
0.5" is not DIN standard and is 12.7mm when exact.
It seems to me that these possible numbers led to inadequate chain.
Moreover if the chain was not calibrated, you may have variations in size between links.
Try to use a caliber tool and actually check a meter or two if your chain links for internal and external sizes to find out if I am correct.

I agree with this. ALWAYS buy calibrated chain. It doesn't take much variance from the standard, for the chain to slip in the gypsy. You do not want this.
A bit off topic, but that's awfully heavy chain for a catamaran, isn't it? Did you think about 10mm hi test chain, G70? There is a French company which makes this so it's available in Europe at least. I think in the U.S. as well.

If you're going to end up changing the chain, you might have a chance to change this too. Edit: Never mind. I just looked up your boat and see that its DRY weight (not even light ship!) is 20 tonnes. What a beast! So the chain size is not a factor.

[UFO]

My Lofrans Gyspy:


https://www.svb24.com/en/lofrans-gyp...mm-din766.html


Did not work very well with 13mm Chain, which the previous owner was running on it. I swapped out for 12mm Chain - With 13mm it was jumping out and skipping, especially when dropping, but now it with 12mm it runs perfectly.

[UFO]

Originally Posted by Dockhead

I agree with this. ALWAYS buy calibrated chain. It doesn't take much variance from the standard, for the chain to slip in the gypsy. You do not want this.
A bit off topic, but that's awfully heavy chain for a catamaran, isn't it? Did you think about 10mm hi test chain, G70? There is a French company which makes this so it's available in Europe at least. I think in the U.S. as well.

If you're going to end up changing the chain, you might have a chance to change this too. Edit: Never mind. I just looked up your boat and see that its DRY weight (not even light ship!) is 20 tonnes. What a beast! So the chain size is not a factor.

I love the heavier chain on my cat - At anchor it really stops you moving around erratically. Been on another 440 at anchor with 10mm chain and you really notice the difference and I would not drop down even for the weight saving.

[Tin Tin]

Your gypsy should have a part number or size stamped on it - what does that say?

[Dockhead]

Originally Posted by UFO

I love the heavier chain on my cat - At anchor it really stops you moving around erratically. Been on another 440 at anchor with 10mm chain and you really notice the difference and I would not drop down even for the weight saving.

Heavy chain is great. Pace Steve Dashew, but when I weighed up the pros and cons of downsizing to 10mm G70 as Dashew recommends, I decided to stick with my 100 meters/330kg of 12mm G40. 1/3 of a tonne!

I don't even need a snubber in anything but gale conditions. The ride in a deep anchorage is PLUSH.

But that's on my 20 tonne mono -- you cats are very sensitive to weight!

[TeddyDiver]

Deeper drop to chain locker helps a lot. Without weight of the chain there's nothing but wisfull thinking holding the chain on the gypsy..

[GordMay]

Originally Posted by TeddyDiver

Deeper drop to chain locker helps a lot. Without weight of the chain there's nothing but wisfull thinking holding the chain on the gypsy..

Indeed. At least 12", to TOP of chain pile.

[YPSILANTI]

This forum is amazing and I've been educated by the informative posts. I've since established that my chain supplier did not provide the correct spec of chain. I now know what the problem is and will resolve it. Thanks so much.

[fxykty]

Originally Posted by Dockhead

Heavy chain is great. Pace Steve Dashew, but when I weighed up the pros and cons of downsizing to 10mm G70 as Dashew recommends, I decided to stick with my 100 meters/330kg of 12mm G40. 1/3 of a tonne!

I don't even need a snubber in anything but gale conditions. The ride in a deep anchorage is PLUSH.

But that's on my 20 tonne mono -- you cats are very sensitive to weight!

Yea and no. Most cats have their anchor near their bows but the chain lockers are generally back around the mast. Extra chain weight is not really an issue.

When we bought our cat it had 65m of 12/13mm G43 chain. The boat has a small chain locker and that amount of chain filled it right up. After a few years cruising we decided that we wanted more chain, so we down sized to 10mm and bought 90m of G80 transport chain. Same overall weight and same size in the chain locker, but 50% longer chain. Just enough length when anchoring 20+m deep, which is usual in Indonesia.

[hpeer]

Originally Posted by TeddyDiver

Deeper drop to chain locker helps a lot. Without weight of the chain there's nothing but wisfull thinking holding the chain on the gypsy..

Now that is a helpful idea. Shudda thunk of that myself.

After a particularly deep anchorage, 120+ feet deployed, 2 problems came up.

Chain started skipping when at short deploy and
Chain would not run out easily.

Related problems. When retrieving the long deployment the chain castled in the locker. Then it binds upon release because the chain hockles and it skips because of insufficient drop.

Bingo!

I will need to smooth the chain lay after long deployment.

But still have a bit of a twist issue.

[Franziska]

How much does the chain wrap around the gipsy in your installation?

We had an issue with slipping chain for a while and it turned out that the chain was not the full 180 degree around. So when the chain moved fast it started to slip. I added a guide which now makes sure that the chain always stays in touch for 180 degrees and that fixed the issue.



Still, not familiar with your specific installation, do not certain if it's a similar issue.