Have you every been on a boat that just wouldn’t stop rocking? Enjoying your time on the water should be the only thing on your mind, not the motion of your boat. Rocker Stopper is engineered to respond quickly and break up the harmonics of waves which cause accelerated rolling. Deployed in under a minute these can save you hours of swaying during a fishing stop or being able to sleep all night. Effective on larger yachts especially when using outriggers or a boom but equally as useful on a smaller skiff hung directly off the side. Single panels work well as drift anchors to keep a boat pointed into the weather. Pairs of panels work well at anchor to counteract roll in both directions.

After researching all the common designs it was obvious the louvered panel is by far the most effective. These allow water to flow up through the panel as it drops then close with only a couple inches of upward movement. The frame and louvers are bu…

After researching all the common designs it was obvious the louvered panel is by far the most effective. These allow water to flow up through the panel as it drops then close with only a couple inches of upward movement. The frame and louvers are built from aluminum that has been given a durable anodized coating. The hinges and fasteners are all marine grade stainless steel.

On the way down the louvers open against stops at 45deg. This lets plenty of water through and closes quickly on the return stroke. The weight of the solid aluminum frame pulls the frame down.

On the way down the louvers open against stops at 45deg. This lets plenty of water through and closes quickly on the return stroke. The weight of the solid aluminum frame pulls the frame down.

On the way up the louvers close and provide resistance. The frame traps water in a box on top of the louvers preventing any sideways motion. A depth of 6’ is sufficient to get the panel below surface chop. There will be a current plume above the pan…

On the way up the louvers close and provide resistance. The frame traps water in a box on top of the louvers preventing any sideways motion. A depth of 6’ is sufficient to get the panel below surface chop. There will be a current plume above the panel from the displaced water.

During the design process the question of stowage and being able to break the panel into a smaller size was heavily weighed. The advantages of having a quickly deployable and stronger panel outweighed a smaller stowage size. We commonly deploy these…

During the design process the question of stowage and being able to break the panel into a smaller size was heavily weighed. The advantages of having a quickly deployable and stronger panel outweighed a smaller stowage size. We commonly deploy these a couple times during a day trip. The panel was kept to 20” wide which is the same width as a bunk. It is about the size of a large beach chair and can fit in most lazarettes.

Deploying the panel takes less than a minute. We usually keep them in their cases, tied on and tucked under the rails. To retrieve the panels slowly pull in the lead line. At the bridles grab the upper two legs which will turn the panel vertical. Pull that thing out of the water like a hoop net full of lobster.

Deployed off a boom, spinnaker pole or both the dampening effect is increased dramatically.

Deployed off a boom, spinnaker pole or both the dampening effect is increased dramatically.

The case is built from heavy duty vinyl mesh fabric. This allows water to drain away and prevents mildew while preventing boat dings. Snaps across the top to secure.  It also doubles as a beach bag while at anchor.

The case is built from heavy duty vinyl mesh fabric. This allows water to drain away and prevents mildew while preventing boat dings. Snaps across the top to secure. It also doubles as a beach bag while at anchor.

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Specifications

Size 20” x 40” x 2”

Surface area - 5 sq ft

Weight - 16 lbs

Frame and Louvers - 6061 Clear Anodized Aluminum

Hinges and Hardware - 316 Stainless Steel

Price per pair $995

Includes cases

Shipping will be quoted

FAQ

Do these really help?

Even in relatively calm seas the amount of current these push to the surface is stunning. This energy is being taken directly from the boat rocking. If there is a broad side swell these will help any boat rock less. Boats larger than 50’ will need multiple pairs . A pair works significantly better than a single panel.

Will they corrode? Will there be electrolysis between the aluminum and SST?

The anodized coating is much harder than aluminum. This will stand up to vigorous cleaning for years without being penetrated. In areas around the hinges and screws where the stainless and aluminum meet small amounts of white corrosion can be expected. This is minimized by using thread locker and is easily cleaned off with a scrub pad. Despite the electrolysis these are still obviously the most durable materials.

Is there a warranty? Can it be serviced?

The Rock Stopper comes with a full three year warranty. In the unlikely event of a louver being damaged the frame can be disassembled. After using a heat gun to remove the thread locker all parts are accessible by removing screws. After disassembling the unit can fit into a space of 2 x 12 x 42. The reassembly is a process best done on a work bench and probably not in a rolly anchorage.

There is a commonly available butterfly version that is cheaper?

The butterfly versions tend to swim side to side in rough conditions. Since there is just one big flap they take quite a bit of motion to engage. If you get outriggers for these they end up costing more and still don’t function as well. Many reports of rusted out mounting points, hinges and low quality cases, it’s built by a BBQ manufacturer.

How can I try them out?

We are located in Santa Barbara and have a demo pair available for local pickup. Seeing is believing and after spending a day on the water we are sure you will see how well these work. Please contact us to arrange a day or weekend.

Are they noisy?

When snorkeling the sound of the louvers closing is very obvious. Above water they are barely perceivable. If you hold the lead line while the boat rocks the vibration can faintly be felt.