Anchor Locker Drainage

We had to discover why links of our anchor chain were starting to rust and also solve the problem.

Maringret carries 70m of 10mm chain in her anchor locker. We noticed that one link had rusted such that it was not safe to use. It was near the end attached to the boat so presumably was low down in the anchor locker and quite possibly sitting in salt water for long periods.

The design/construction of the HR41 had one drain on the starboard side which was approximately 10mm inner diameter. Depending on sailing conditions there could be salt water sitting in the bottom of the anchor locker for extended periods of time. Certainly with the wind in from starboard and the boat heeled to port the water could stay there indefinitely.

We decided to attack the problem in two ways: first we decided to remove the original drainage fitting and replace it with a pair of larger drain. Secondly we decided to have a stainless steel grating fabricated which kept the chain about 2cm above the floor of the anchor locker where any salt water could sit we called this an “anchor chain pallet”.

The new drains were a standard fitting from the chandlery with an inner diameter of 14mm, we removed the original, enlarged the hole to accept the new fitting and then sealed the hole with epoxy to keep water from making its way into the fibreglass of the hull. Once that was done we fitted the new drains with SikaFlex which makes the seal waterproof while leaving the option of removing them in the future should the need arise. The new drain on the port side was drilled to match the original on the starboard side and fitted in an identical manner. The angle on the drain hole was made so the entry of the drain hole was flush with the floor of the anchor locker.

For the anchor chain pallet we made a pattern in cardboard and then thin plywood so that it sat about 2cm above the floor of the anchor locker. It was made in what is called “perf” stainless which is sheet stainless with holes drilled every 10mm or so. By drawing the legs as folds we got away with the cost of cutting out the material and then 3 folds. Not only isit cheaper to avoid welds but we preferred not have any welds that might sit in water. The factory fitted attachment point for the anchor chain is roughly in the middle of the anchor locker floor. We had a hole cut in the pallet to provide an opening for the chain to attach to the fixed eye. Then in case the chain was to catch on the edge of the perf floor, we had a length of pipe welded on the underside to effectively function as a leg for the middle of the raised tray – but in reality it primary function was to prevent any edges being exposed for a link of chain to snag on.

ip41_anchorChainPallet

Now the chain sits above any residual water, also there are twice as many drains and also drains of a larger diameter to shed any water that comes in with the chain when it is lifted aboard.

Since installing the pallet in the anchor locker, there has been no appreciable rusting of the anchor chain.


© The contents of this site are the copyright property of the authors.  Visitors may read, copy, or print any material for their own use, free of charge.  No material printed or copied from this site, electronically or in any other form, may be sold or included in any work to be sold without explicit permission from the authors.