The real issue with swivels is not the breaking strength in a straight line. Many brands can claim a breaking strength as high or higher than the chain then connect to.
The real of concern is their susceptibility to side loading and other mis-aligned loads.
If the anchor is fixed in position either because of rocks or a deep and secure set, the problem with most swivels mounted on the anchor itself is that they can not well orient to a pull from the side as the result of a wind shift.
The Wasi is a certainly a bit better at this than some, but once the pull is more than 30 degrees from axis of the anchor shank, you have the full load of the rode as a bending force on the small stem of the ball. It bends and, potentially, breaks. Exactly as Mark and Porter observed.
The solution is either a better designed swivel, or to put a few links of chain between the swivel and the anchor shank so side loading can never happen.
Annapolis, MD, USA
---In amelyachtowners@..., <milesbid@...> wrote :
I have also used the Wasi PowerBall swivel for many years along with the WASI anchor and chain. According to tests reported by WASI, the swivel is significantly stronger than the strongest chain. Anyone not familiar with it would probably enjoy looking it up.
Regards to all,
s/y Ladybug , sm 216, offshore in Gulf of Maine, heading south to Cape Cod