All chain is the gold standard that long distance cruising boats should be aiming for. With reliable boat anchor
winches and high tensile G7 chains the weight disadvantage is less important than ever.
If you are ever caught out having to use to use a line rode
in a coral, rocky or foul bottom where there is a significant abrasion risk, there are a couple of solutions. Even if you have all chain rode
these options are worth noting in case you lose your chain.
1. Adjusting the scope
so the rode is above the bottom.
While we think of anchor holding power as related to scope
it is really related to the angle of pull of the anchor shank off the bottom. If there is one link of chain left on the bottom the anchors holding ability is not practically improved by letting out more scope.
If you are diligent enough to adjust the scope based on the wind
strength and current
so that the rope
is above the hazards, but there is always some chain on the bottom your holding ability will not be compromised. There comes a point with stronger wind
where this is not possible and the chain will lift
off the bottom, but this happens with an all chain rode at only a slightly higher windspeed. In some anchorages
dead lumps of coral, rocks or debris can be a long way off the bottom and the system does not work (as well as live bommies, but you should avoid contact with these anyway for the health
of the coral). With these cautions in mind it can work surprisingly well.
In light wind you need to be prepared to adjust the scope to very low numbers (less than 2:1 if you have little chain).
2. Buoy the rope rode.
The idea is much as above, but to create an automatic system. In strong wind the force will still sink the rope and it will work normally. The floating rode is a hazard to other boats and this risk needs to be considered.
Originally Posted by Franziska
Dynema is very chafe resistant.Would it be strong enough in coral areas? Coral specialists,looking forward to your comments.
I am surprised there are no reports of sailors using dynema for an anchor rode. In abrasion resistance it would lie somewhere between chain and conventional nylon or polyester rode. One drawback is that it floats, but this could be overcome with a kellet or a small amount of weight added to the core
(like leaded line).