GMac
New member
Re: Not trying to be smart ... just confused ..
[ QUOTE ]
The problem is: how to lower the extreme stresses created when a chain already under some tension suddenly has to cope with the additional snatch of a boat sailing around it's anchor (or pitching in a wave). So we're talking 30kts wind plus . . . when there's not much catenary, and what catenary there is left (your expression - buffering?) will only give you centimeters of spring.
[/ QUOTE ]
A few cm or not the forces required to get those can be very large which creates the damping effect.
Nothing wrong with rope, so much so every rode must have some at some stage. On all chain when the wind starts to really pipe up and additional 'stretch' is good. In nicer weather possibly not as there is enough in the chain itself. The 'stretch' in that case is the forces required to get the chain into a situation where it is about to lose any curve or sag it may have left. Those forces are quite large.
X squared by the dingle dangle of the dodacky maybe, not that I have the slighest idea what that actualy does/is/means or whatever. All I know the easyest way in most cases to stop people dragging is to add a bit more chain. Do it very often (multiple time a day at this time of the year) and it works. Simple really.
This is not a thing that happens often with all chain rodes. We will shortly start replacing chains on cruisers heading off next season. Some willl be due to wear or rust and use the same size. The chances are very very high we will swap some on some US boats which will go up at least one size. Why? It increases the holding, which they found on the way down was not the best. This is usually as they did a common US thing and used small but high grade chains. Saved weight, have high strength, spent a pile of money but all that don't mean squat when your sliding around the Pacific.
I think this thread also has a few things to keep in mind. the word 'catenery' and 'holding' are being used possibly not quite in the right or best way in some posts, mine included. Also some people are talking at extreme end of things, which in reality 99% of boats will never actually do. Interesting stuff though all the same.
I'm off to get my numbers and have the last full day of pre-Xmas punters making me what to kill someone /forums/images/graemlins/smile.gif A bit like a full moon at the office at the moment.
[ QUOTE ]
The problem is: how to lower the extreme stresses created when a chain already under some tension suddenly has to cope with the additional snatch of a boat sailing around it's anchor (or pitching in a wave). So we're talking 30kts wind plus . . . when there's not much catenary, and what catenary there is left (your expression - buffering?) will only give you centimeters of spring.
[/ QUOTE ]
A few cm or not the forces required to get those can be very large which creates the damping effect.
Nothing wrong with rope, so much so every rode must have some at some stage. On all chain when the wind starts to really pipe up and additional 'stretch' is good. In nicer weather possibly not as there is enough in the chain itself. The 'stretch' in that case is the forces required to get the chain into a situation where it is about to lose any curve or sag it may have left. Those forces are quite large.
X squared by the dingle dangle of the dodacky maybe, not that I have the slighest idea what that actualy does/is/means or whatever. All I know the easyest way in most cases to stop people dragging is to add a bit more chain. Do it very often (multiple time a day at this time of the year) and it works. Simple really.
This is not a thing that happens often with all chain rodes. We will shortly start replacing chains on cruisers heading off next season. Some willl be due to wear or rust and use the same size. The chances are very very high we will swap some on some US boats which will go up at least one size. Why? It increases the holding, which they found on the way down was not the best. This is usually as they did a common US thing and used small but high grade chains. Saved weight, have high strength, spent a pile of money but all that don't mean squat when your sliding around the Pacific.
I think this thread also has a few things to keep in mind. the word 'catenery' and 'holding' are being used possibly not quite in the right or best way in some posts, mine included. Also some people are talking at extreme end of things, which in reality 99% of boats will never actually do. Interesting stuff though all the same.
I'm off to get my numbers and have the last full day of pre-Xmas punters making me what to kill someone /forums/images/graemlins/smile.gif A bit like a full moon at the office at the moment.
