Originally Posted by braidmike
We are within a year of begining our circumnavgation. Most of the systems on our old Ericson 35 have been rebuilt/replaced, the latest being the addition of a Maxwell windlass. The next step is the purchase of 5/16 hi-test anchor chain. The question: HOW MUCH?? Our anchoring ground will vary from leaving Southern California, to the standard stops on an around the world trip of ten years (the wildest current guess). From what I've been able to read and gather, anchoring in up to 80' may be inevitable. A half keg of chain is 270' (what I have now, just some oddball size that doesn't seem to match anything else manufactured in the world). Along with 250' of octabraid on the main, I'm hoping that will be sufficient. The old chain will be used for the stern anchor (at least the 200' that is still not too corroded). Any advice from those that have been?
I'm not entirely sure how to interpret "the standard stops on an around the world trip of ten years", as ten years is more than enough time to make some considerable detours from the 'usual milk run'. That said, deep water is probably unavoidable as a lot of it is in your way across the Pacific.
Chain length required depends almost entirely on this, so discount any thoughts of catenary, helping the anchor, and other misconceptions.
On Kiwi Roa
, the two main anchor rodes are 100 and 50 meters chain respectively, plus 50 and 100 meters respectively of 8-plait polyester. "From those that have been", this is more than adequate.
The main reason I am responding is to suggest you reconsider your choice of 5/16" hi-test. We would go with 1/4" high tensile G70, which saves about 35 lb per 100' of length and is still stronger. (Well actually out of the US and given an international cruising area we would be going with metric sizing but that's beside the point). There is no need to carry the extra weight of medium-lower tensile grades.