I was always amazed at how much water could seep through the chain-pipe and into Toscas anchor locker when a sea was up or we were punching into a head sea-although punching would hardly describe the ungainly motion of a gaff-rigged ketch to weather. Wallowing? Submarining? Regardless, a waterfall greeted whoever dared venture into the v-berth to check on the strange gushing noises. Still, I was happy to have a three-inch diameter hole rather than one of the ice-cream scoops that some contemporary boats have on their bows (see Practical Sailor March 2011).
Anchor lockers are a convenience to coastal cruisers but no friend to offshore sailors. Passagemakers often forgo a deck-clearing locker for a belowdecks anchor-chain well. An angled spill pipe leads the anchor chain from the deck to the well, which often is under the forepeak and behind a watertight bulkhead. The setup not only eliminates the flooded-bow worries inherent with an on-deck locker, but it also moves the chain and anchors weight lower and further aft, where it should be to avoid hobby-horsing.
To keep water out of the belowdecks chain box, you first must keep water from pouring down the spill pipe. We have heard of numerous methods to seal a deck hole-from Silly Putty and duct tape to threaded brass caps and rags-and most of them work in most conditions. The hole-stopper methods PS contributors have found to be effective in even the heaviest of weather (when a boarding sea can create a fire-hose effect) include:
Teak plug: Sized to fit the deck hole and about 6 inches long, with an eye for attaching the chain to the bottom (after its removed from the anchor) and a fitting on top for pulling it out later. Remember that wood will swell when it gets wet, so you may have to pull it out with a halyard. As the wood gets wet, it swells to seal the hole. PS contributors and circumnavigators Evans Starzinger and Beth Leonard use a Delrin plug in the same way, but they bed it with silicone before getting underway.
Closed-cell foam (from a cushion, Nerf ball, or the Forespar TruPlug): PS Technical Editor and bluewater sailor Ralph Naranjo suggests squeezing closed-cell foam like a rubber rivet into the aperture.
Other tried-and-proven methods include leaving the anchor on and spraying canned expanding foam insulation into the hole (this dislodges easily when the anchor is dropped); shoving a tennis ball into the chain-pipe (for a chain still attached to a bow anchor, split the ball half-way and pass the chain through it); cramming a rag into the hole and spraying foam insulation over it.
Id love to hear how others have solved this age old problem.