Anchor Chain Twist Nightmare

[robifz]

I have 80metres of 1/2inch anchor chain with a vertical anchor winch. The bow roller has a groove to hold the chain in place and I have vertical fall of about 3-5ft in the anchor locker. But when I pull up the chain I can see that it is ever so slowly putting a twist in the chain. The more times I anchor the more the twist is. After about every 20 times I anchor the twist is so much that I cannot drop the anchor anymore as the chain will jam in the chain pipe hole. If I am normally dropping 40m of chain the twist starts to develop around the 35m mark.

I can get around the problem by dropping the entire 80m of chain in about 20m of water and then slowly retrieving. If I already have a large twist I cannot do this and I need to pull out the chain by hand from the locker and untwist manually. Not easy with 1/2inch chain. Good for the muscles maybe but I am fed up with it.

I would like to solve this problem but I cannot figure out why this twist is being create. I would like to know what is the engineering thought behind how this all works.

My possible thoughts are:
- chain comes in to gypsy at 12oclock and exists gypsy at 8 oclock - that is goes 3/4 around before being stripped into the pipe. Maybe this is causing the twist and maybe it needs to go around the gypsy more?
- Vertical anchor winches always have this problem?
- Grooves in bow roller of gypsy are not correct pattern to hold chain in place?

Any advise would be much appreciated as I have been suffering from this problem for many years.

Rob

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