a couple of things to think about:
1) Will the windlass accept chain?
2) (If it does accept chain) If the windlass accepts chain it most likely requires the chain and line be spliced as many do not accept a thimble and shackle.
3) (If it does accept chain) What is the max size chain the windlass will accept?
4) Does the windlass require 3 standline line, or will it accept braided line?
As far as chain goes, "More is Better". If you go with a shorter length, then go with heavier chain. You will more than likely be restricted by the max. chain size of the windlass. Some recommend the chain be equal to the length of the boat. I'm using 30 ft. of ss, which I think is 5/16. I have 200ft. of braided line that I belive is 1/2", however the breaking strength on the braided is higher than that of 3 strand. Based on the chart from BoatUS (Below) I think 1/2 would be fine. I don't have a windlass.
[TABLE="class: zebra"]
[TR="class: odd"]
[TD="colspan: 5"]Suggested Minimum Working Rode Sizes*
(For winds up to 30 knots.)
[/TD]
[/TR]
[TR="class: even"]
[TD="width: 14%"]L.O.A.
[/TD]
[TD="width: 18%"]Beam (Sail )
[/TD]
[TD="width: 20%"]Beam (Power)
[/TD]
[TD="width: 21%"]Nylon Rode
[/TD]
[TD="width: 27%"]Chain Rode
[/TD]
[/TR]
[TR="class: odd rowHover"]
[TD]10'
[/TD]
[TD]5'
[/TD]
[TD]5'
[/TD]
[TD]125’-3/16”
[/TD]
[TD]3/16”
[/TD]
[/TR]
[TR="class: even"]
[TD]15'
[/TD]
[TD]7'
[/TD]
[TD]7'
[/TD]
[TD]150’-3/8”
[/TD]
[TD]1/4”
[/TD]
[/TR]
[TR="class: odd"]
[TD]20'
[/TD]
[TD]8'
[/TD]
[TD]9'
[/TD]
[TD]150’-3/8”
[/TD]
[TD]1/4”
[/TD]
[/TR]
[TR="class: even"]
[TD]25'
[/TD]
[TD]9'
[/TD]
[TD]10'
[/TD]
[TD]150’-3/8”
[/TD]
[TD]1/4”
[/TD]
[/TR]
[TR="class: odd"]
[TD]30'
[/TD]
[TD]10'
[/TD]
[TD]11'
[/TD]
[TD]200’-7/16”
[/TD]
[TD]5/16”
[/TD]
[/TR]
[TR="class: even"]
[TD]35'
[/TD]
[TD]12'
[/TD]
[TD]13'
[/TD]
[TD]300’-1/2”
[/TD]
[TD]3/8”
[/TD]
[/TR]
[TR="class: odd"]
[TD]40'
[/TD]
[TD]13'
[/TD]
[TD]14'
[/TD]
[TD]400’-5/8”
[/TD]
[TD]7/16”
[/TD]
[/TR]
[TR="class: even"]
[TD]50'
[/TD]
[TD]14'
[/TD]
[TD]16'
[/TD]
[TD]500’-5/8”
[/TD]
[TD]7/16”
[/TD]
[/TR]
[TR="class: odd"]
[TD]60'
[/TD]
[TD]16'
[/TD]
[TD]19'
[/TD]
[TD]500’-3/4”
[/TD]
[TD]1/2”
[/TD]
[/TR]
[/TABLE]
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