Anchor Systems

Maringret’s anchoring systems needed an overhaul. She had 75m of 10mm chain with a 20kg Bruce on the end.

Maringret’s anchoring systems were an odd combination of things:

  • inoperative (the rusted main anchor windlass)
  • unsolved (deploying and retrieving the second bow anchor)
  • absent (no stern anchor)

We needed to find solutions for these items, some were direct replacements, others needed a solution designed.

Replacing the Windlass

Maringret came to us with a 800 watt Lofrans anchor windlass. The early HR 41s had the anchor windlass mounted at the aft end of the bowsprit which proved a great recipe for collecting green water. Obviously Hallberg-Rassy found that out because by the end of production the windlass was mounted on the deck aft of the anchor locker. The anchor windlass was rusted solid and needed to be replaced and now we needed to make that same change.

Our old windlass was more or less a block of rust, the connections were oxidized and rusted and it worked intermittently. We used it once and it refused to lift the anchor when the wind picked up during the night. Luckily we had anchored in shallow waters and were able to lift the anchor manually. From then on we were aware that we had no reliable method of retrieving the anchor.

We knew from our sister boat Bodil (hull 101) that by the final (5th)  year of production the anchor windlass was a vertical axis model with the electric motor mounted below the deck aft of the anchor locker. Her windlass was 800 W which was the same as our horizontal shaft model. While we were moving and relocating the windlass we decided to increase our power to 1,200 W but there was no vertical mounting model available from Lofrans. We ended up with a horizontal axis windlass rated at 1,200 W.

Placing the Windlass

If the windlass is mounted directly onto the deck then the direct line from the chain gypsy to the anchor rollers will cause the chain to touch the teak toe rail, therefore the windlass must be raised up from the deck. Because of the extreme loads on the windlass the base mounting must be sufficiently strong. We had ours made from 5mm 316 stainless steel sheet. The box was welded on all edges with the bottom scalloped to tightly fit the deck curvature. Extra length 10mm bolts them passed through the windlass casting, through the deck and through a backing plate. The spurling pipe which carries the anchor chain to the anchor locker (not to be confused with the hawse pipe which leads the anchor chain from the water onto the deck and is not present on most sailing  boats) is made with XX stainless pipe which is welded onto the top and bottom faces of the windlass base, it then extends through the deck and finished about 25 mm below the deck.

The angle of incline on the spurling pipe needs to be steep enough to keep the chain moving once the windlass feeds it down. A vertical drop into the chain locker would be the best but in our case this would have meant relocating the anchor locker into the forepeak and most likely interrupting the 2 berths up there. We needed to use an incline to lead the chain forward beneath the deck: too steep an angle and we could not stack all the chain under the spill point, too shallow an angle would give us enough height for the chain to pile but the friction would stop the chain sliding down under its own weight.

We could not find anything on such angles in either books or on websites and couldn’t really try it out in situ without cutting a hole through the forepeak-anchor locker bulkhead. We reasoned that when the chain comes aboard it will always be wet (and if it isn’t wet then we are probably dealing with a bigger problem) and that wet materials have a lower coefficient of friction than dry. The spurling tube is made from machine finished 316 stainless and doesn’t offer a lot of friction or holds. The chain links are cast steel coated in zinc and provide a greater degree of friction than stainless steel. We set up some chain on a table and tried various angles to see when the friction would be enough to overcome the weight of the hanging chain. Another factor that enters is that the more chain hanging (i.e. the taller the chain locker is) then the greater the downwards pull on the chain in the spurling pipe. In our case the length of our fall was somewhat less than we would have liked.

In the end we settled on the following dimensions which we derived empirically:

Dimension Amount Comment
a) height of windlass base this must be high enough for the anchor chain to clear the teak toe rail
b) distance aft from anchor locker the windlass base must be far enough back from the edge of the anchor locker to allow room for the spurling pipe etc; the further it is aft the lower the spurling pipe will emerge in the anchor locker (meaning the less chain that can be stacked under it). We could have mounted the windlass 30 cm further forward but it would have been more difficult to change gas bottles etc.
c) angle of spurling pipe if this is too shallow the chain will stop sliding due to friction
if this is too steep then it will reduce the height available for chain stacking in the anchor locker
d) height of spurling pipe exit this is determined by b) and c); the higher this is the more stain can be stacked under the spill tray
e) angle of spill tray this does not need to be the same angle as c)
f) extent of spill tray this dimension should deliver the chain so that it falls over the most optimal point on the bottom of the anchor locker, usually this would be the middle of the bottom, in our case we had this slightly towards the front due to the sloped front wall of the anchor locker.
g) spill tray height this is determined by all the preceding values; the greater this value the more chain can be stacked before there is a “chain jam”; the greater this value the greater the downwards pull on the chain in the spurling tube.

Spurling Pipe

Our spurling tube is in 2 pieces:

  • the upper portion is welded into the windlass base;
  • the lower extends from under the deck to the spill tray.
The lower piece is sized to fit over the upper piece so a join can be made between the two pieces. A round flange plate is welded onto the lower portion where the spurling pipe will pass through the bulkhead. The plate is on the forward side of the bulkhead and is mounted with 4 M6 bolts and Sikaflex on both sides. Once through the bulkhead flange the spurling pipe turns into a spill tray, which fans out to each side so the chain can fall across the anchor locker. The spill tray has 40 mm sides on it to contain the chain. Welded under the forward edge of the spill tray is a section of 25 mm stainless tube so there is a round edge for the chain to run over (remembering that the chain must run freely up and out of the anchor locker as it does coming in). Once the installation was in place and we ran trials we found that when the anchor is dropped the chain can exit at such a rate that it can jump up and out of the spill tray, we had a bar welded over the top of the edge of the spill tray to contain the chain down onto the spill tray.

Second Anchor

The HR 41 was built with a bowsprit carrying 2 bow rollers. The starboard bow roller has nylon sheaves that are milled to fit chain, the port sheaves are milled to fit rope. The main anchor is run on chain using the starboard roller with the chain being lead back to the windlass gypsy and then down into the spurling pipe. It has remained a mystery how the second anchor is to be run. The standard anchor windlass has a rope drum on the port side so this fits with the port side bow roller, what is not clear is how to manage the rope: without tension being maintained on the rope the drum does not grip the rope. Also all anchor rodes should have chain near the anchor and although the chain will run across the nylon sheave, the rope drum on the windlass will not grip it. This means that as long as a crew member is assigned to maintain tension on the rope the rope may be brought aboard but not the chain. Without a spurling tube leading to an anchor locker the rope (and chain) also can not be stored immediately but rather must accumulate on the deck. The nature of the rope drum is that even if a spurling pipe was fitted on the port side, there would have to be enough weight on the the drum to maintain friction for pulling in the rope. Half a meter of chain is enough when using a chain gypsy but for the rope drum it would probably require 10 meters or so of rope hanging, not exactly something that can be fitted on a sailing yacht.

We have talked to other HR 41 owners and also owners of other boats which have the same anchor configuration. We have not yet met anyone who has come up with a successful method of using both anchors. There are a number of issues to be resolved with such an anchoring system:

  • both sides must be able to handle chain as a substantial proportion of the holding power of anchor comes from the weight of the chain lying on the ocean floor – rope on the ocean floor does not have anywhere near the same amount of holding power.
  • each side must be able to be taken out of the retrieval system as required – this implies a clutch mechanism for each side. With a rope drum this is provided by releasing the rope tension. If a chain gypsy were to be fitted on the port side then there would be no clutch mechanism on either side.
  • a system to remove the starboard chain from the retrieval system is required even to retrieve the rope on the port side
  • if chain is to be fitted on both sides (i.e. swap the port side rope drum with a chain gypsy) then a spurling pipe and anchor locker are required for the port side. This could be achieved by installing a second spurling pipe which leads to the existing anchor locker and then dividing the anchor locker in to 2 portion side by side.

We decided to start with a compromise solution: existing chain on the starboard side and rope on the port side. Rather than install a second spurling pipe on the port side we resigned ourselves to retrieving the rope by a crew member maintaining friction on the rope drum.

We segregated part of the top level of the anchor locker to store the rope, the rest of the top layer was dedicated to the cooking gas storage (click here for more details).

The port side anchor locker lid must be up in order to stow the rope, as of yet we have not figured out exactly what to do with the chain on this anchor rode.

Stern Anchor

Most production do not come with a factory designed and fitted system for deploying a stern anchor, the HR 41 is no exception. Many places where boats moor side by side with the bow to a dock or quay there is a need to be able to manage a anchoring point to the stern. On the Maxi the hull was fairly close to vertical and there was a rigid pushpit to balance against while deploying or retrieving the stern anchor. Also the Maxi 95 was less than 2/3 of the HR 41 in displacement and so the required anchor was that much smaller. On the HR 41, the hull is rather vertical but there is a lovely teak toe rail and a lack of rigid pushpit to brace against. Combine this with the need for a heavier anchor and it is rather dangerous to try and deploy the stern anchor freehand.

We had seen some larger HRs which had mounted a powered anchor windlass on the aft deck, much akin to the setup on our foredeck. For boats with lazarettes this would work fine as the cabling and mountings can be out of sight in the lazarettes but the HR 41 does not have proper lazarettes and so any fittings would be into the aft cabin. We decided to fit a semi-permanent stern roller on the aft deck and transom. “Semi-permanent” in the sense that the fitting could be removed rather easily when not needed.
We went with a 3-piece solution: the main piece being the “stowage trough” which incorporates the roller. We sized this to a specific anchor – the 15 kg Bruce. We went with a Bruce because it is rigid and easier to handle. We would have liked to use a bigger anchor but the space between the teak toe rail and the teak bench seat limited what options we had. Also this anchor is to hold the boat off a fixed dock, not the primary anchor for riding out bad weather.

The other 2 pieces were the supports: one on the deck and the other on the transom. Both obviously had to be able to support the loads although this fabrication is for the deployment, retrieval and storage of the the anchor – not the load while deployed as the stern cleats will take those loads. The fitting on deck was made rounded so if bare feet hit it there wouldn’t be sharp corners to cut and main. The transom fitting was designed for easy removal of the “stowage trough” and the permanent fitting to not have anything that could snag lines.

  • We couldn’t find any published information on the parameters for designing an anchor storage system and so derived ours empirically.
  • The spurling tube must operate equally well in both directions, in fact when the anchor is falling and pulling chain up and out of the locker the risk of damage is much higher should the chain catch on something.
  • The spurling tube and spill tray are a system that is almost entirely hidden inside the boat, in which case functional is much better than pretty.

We’ve collected maintenance information on our Lofrans Tigres windless maintenance page. We have another anchor page for our HR41 located here. As well as our modification to our anchor locker located here. And of course our annual maintenance of the anchor chain is here.

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