Common fit challenges

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This section outlines some of the common fit challenges which Rocna owners can come across when attempting to install the new anchor on an older vessel, the bow roller of which is designed perhaps for a specific anchor type and size. Some of these problems are common, and there can be simple and cheap solutions in many cases.

Issues with the roll-bar

The roll-bar on the Rocna can unfortunately represent a problem with certain roller designs, if the roll-bar should clash with a forward projection such as a bowsprit, or the underside of a platform.


This is an issue with some sailboats, if their anchor bow roller(s) are designed as part of the bowsprit arrangement. Many yachts with bowsprits incorporate a roller directly next to the 'sprit itself. A Rocna, with its roll-bar, cannot fit in such a location. Moreover, the whisker and bob stays can present an additional challenge.

Without modifications

In many cases a simple two-part tackle could be used, led around the anchor's roll-bar and back, to pull the Rocna home into a suitable position if it cannot be pulled completely home onto the bow roller. For example, the anchor may be perfectly happy snuggled up against a bowsprit, with only the shank supported by the roller. To prepare to deploy, the line retaining the anchor via the roll-bar is let go, and the anchor swings down on the roller, ready to go.

A new place for the anchor

Bowsprits and their associated stays are sometimes such an issue that it can be worthwhile installing a dedicated spare man, in a position that allows the anchor and rode to deploy and stow clear of all obstacles. This does not have to be too involved, and a regular bow roller mounted to the side of the bowsprit can typically work well. This solution is probably the best to consider, particularly with a new vessel design or build.

For those boaters mindful of nautical tradition – and it may be assumed that this is more likely with those sailors partial to bowsprits – this is a suitable concept. On sailing ships of old, anchors were commonly stored back on the main hull, and launched from spare men, kept well clear of the extensive and complex bowsprit rigs.

The roller needs to be held out forward enough that the anchor can clear the hull, and the bowsprit's whisker stays. This will probably involve a longer projection than normal, which may be necessary in any case if the windlass has been located close to the bow, not leaving enough room for the shank of the anchor to come back over the foredeck. The bowsprit will obviously require that the roller be located to one side or the other, also necessary for the anchor and rode to clear the bob stay. The spare man can therefore be placed at an angle rather than being oriented fore-and-aft. A roller or a wooden Sampson post can serve to re-route the rode as required, if the windlass is not a vertical capstan or for whatever reason cannot tolerate the altered angle.

This forward and lateral positioning of the anchor is not likely to be an issue in the same way that projecting the anchor relatively far out normally would be, as it should be able to fit into the space defined by the bowsprit and its stays. However, the roller being located a significant distance from the deck can be a problem with regard to strength; the entire roller assembly needs to be strong enough to hold the anchor securely against solid water while at sea, and to deal with loads while anchored. If the latter case cannot practically be handled, a snubber or bridle can be used while anchored to take the load from the roller and place it instead on foredeck cleats or chocks via fairleads.

The below photos are of custom fabricated roller assemblies intended to both stow and deploy a Rocna anchor.

Tayana 37 with custom built spare man
Tayana 37 with custom built spare man  
George Buehler designed "Juna" with custom extended roller
George Buehler designed "Juna" with custom extended roller  
Magellan 36 with over-sized Rocna clear of bowsprit and whisker stay
Magellan 36 with over-sized Rocna clear of bowsprit and whisker stay  

Lowering the roller

Depending on the design of the bowsprit arrangement and its existing rollers, it may be appropriate to simply drop the anchor downward a little, by lowering the roller so that the roll-bar of the anchor remains clear of the bowsprit when it is home. Moving the roller slightly outward (sideways away from the 'sprit) will also help, and minimize the vertical adjustment necessary.

The roller(s) can be lowered by simply installing a fabricated assembly consisting of aluminium or stainless steel cheek plates. These could extend low enough to meet the upper surface of the fluke of the anchor. The anchor is then kept safely contained when it is pulled home, and the rode is also secure on the roller when deployed.

Customized roller assembly at front of bowsprit

Moving the roller to the front of the bowsprit

On short bowsprits, or those with substantial platforms integrated into them, it may be appropriate to install a regular roller assembly at the front, whereby the anchor will stow and launch as on any regular bow roller.

This is probably the least desirable solution, as it places the anchor's weight at the far front of the vessel, and also means that the bowsprit must be strong enough to handle the forces in the rode. With many vessels this is unlikely to be the case; while it may be acceptable to stow and launch the anchor from this position, the rode when deployed will need to be taken up with a snubber or bridle brought back to the main hull.

Platforms with enclosed rollers

Typical situation with a Rocna on an enclosed platform

This is an issue with some powerboats, if their anchor bow roller(s) are embedded and enclosed in a forward projecting platform. A Rocna, with its roll-bar, may not be able to be pulled home completely, should the roll-bar strike the underside of the platform earlier than desirable.

Without modifications

A possible solution may be to simply accept the attitude in which the anchor finds itself; it may be acceptable if not ideal. This depends on how far the anchor can be retrieved, and if its final position can be made stable. For example, Bill Parlatore, editor of PassageMaker magazine, uses a Rocna 25 on his powerboat Growler. As shown in the photo, the anchor does not sit as well as may be thought ideal. Nonetheless Bill is happy with this arrangement, and the anchor self-launches and comes home without problem.

(For more photos of Bill's anchor set-up, please read the PassageMaker review of the Rocna).

As described above in the section about bowsprits, it may be quite acceptable to use a simple two-part tackle, for example around the roll-bar, to pull the anchor up into a suitable position if it cannot rest ideally on the roller assembly. The anchor then is stowed effectively by this lashing. To prepare for deployment, the line is let go and the anchor simply swings on the roller.

Lowering the roller

Typical concept drawing of a lowered bow roller. Click here to view the PDF with full notes.

Dropping the anchor downward so that the roll-bar is positioned just directly below the platform is one of the easiest and most elegant solutions. It also has the advantage that weight is slightly lowered, always a desirable outcome on any boat.

The idea is to position the primary roller lower than the positioned drawn by the original designer. Typically, rollers are placed inline with the platform itself, to accommodate a specific plow or claw type, and it is this situation where the Rocna is likely to present problems.

The new roller will need to be positioned lower by adding cheek plates, or extending any existing ones, below the platform. Frequently a second roller will also be required in order to handle the changed route for the chain, and to help position the anchor in the correct attitude when it is pulled home. These rollers and the cheek plates would ideally follow the guidelines presented in the Bow roller assembly design section.

The concept drawing on the right shows a possible solution for the anchor platform on a Selene 59. The original design was intended for plows, and incorporated dual rollers on a pivoting assembly. The pivot is unnecessary with the Rocna self-launching design.

Moving the roller to the front of the platform

An obvious solution is to simply replace the enclosed roller with one at the end of the platform. This is not as ideal as a re-designed roller assembly lowering the roller and anchor, but avoids the requirement to fabricate cheek plates and provides easy access to the anchor and rode.

If possible, the new roller could be positioned off-center, so as to allow the current roller to remain in use, perhaps with a second anchor, if desired.

Customizing the platform to accept the roll-bar

This solution requires the most work and permanent modifications to the platform itself; however, it yields what may be considered the best result. The slot in the platform for the anchor simply needs to be re-shaped to accommodate the roll-bar, in such a way that it may freely come home without striking the underside of the platform.

Pictured is the platform on a Hatteras 50, with a custom built aluminium roller surround which replaces the factory original. It contains dual rollers and opens up space at the front of the platform for the roll-bar, while remaining enclosed. A secondary roller is included at the forward port.

Modified platform on a Grand Banks 46 with Rocna positioned for its roll-bar to just clear
Modified platform on a Grand Banks 46 with Rocna positioned for its roll-bar to just clear  
Rocna 55 at home surrounded by custom built roller assembly on a Hatteras 50
Rocna 55 at home surrounded by custom built roller assembly on a Hatteras 50  

Pins and retaining bolts

Existing rollers may feature retaining pins designed to fit through a hole in the matching anchor, or over-the-top bolts or latches designed to both secure the anchor when home and chain when deployed. The shank on the Rocna is relatively tall when compared with some other anchor types, particularly CQRs (articulated plows). This may require modifying the pins, or removal altogether.

Moreover, please note that we advise against the use of through-shank retaining pins. For more, please consult the Anchor retainment section.


This 22 m cutter displacing 80 t was designed for small stockless anchors, stowed in hawsepipes. Dissatisfied with the performance of these anchors, the owner is upgrading – however, the yacht has no way of storing its new Rocna 110, and will require significant modifications.

Hawsepipes are designed for symmetrical stockless anchors, a category of ground tackle suited to large vessels which require the guaranteed ease of stowage and handling associated with a symmetrical pattern.

An asymmetrical design allows far greater performance to be extracted from the anchor, but this choice makes all small boat anchors incompatible with typical hawsepipes. They can only stow on their roller in one orientation, and are designed with shank shapes and other factors intended to facilitate this. Unfortunately, hawsepipes are found on some small vessels where they are entirely inappropriate and their inclusion in the design owes more to a misplaced pining for tradition than any mind for practicality.

A modified style of hawsepipe, essentially a steeply tilted albeit enclosed bow roller, could be designed to accept a Rocna, providing enough space was made available in the pipe itself for the anchor's shank, and an adequate receptacle space provided for the fluke and roll-bar. This concept has some advantage in that it keeps the anchor weight low, and removes the anchor from the bow of the vessel which may be desirable for various reasons. However it is unlikely to be practical on small boats, where the internal space lost to the hawsepipe would be considered unacceptable.

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