Drag Tests

Hydromer’s Drag Tests on Lake Hopatcong, New Jersey, consisted of a weighted row boat being pulled by powerboat, connected via a tow line and a force gauge. The reduction in towing force was found to vary from no reduction at 3 knots to 17% reduction at 20 knots.

The data correlations were very good for anti-fouling coating alone (+0.937) and with the Sea-Slide Formula coating (+ 0.963).

 

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Studies pertaining to using Sea-Slide Formula over anti-fouling bottom paints

A 2004 study by Sharif University of technology, Tehran, Iran, titled, “New Technologies For Reducing Fuel Consumption In Marine,” concludes: “Sea-Slide coating reduces friction between hull and water and can be used over most anti-fouling paints. This is a unique coating with excellent drag reduction and can be used on personal water craft to improve speed and handling; on boats to improve speed and fuel consumption; on any other craft where reducing the drag through the water is important.”

We at Hydromer Inc. have devoted extensive laboratory and fields testing to prove that the Sea-Slide coating is not detrimental to anti-fouling paints in any way and allows the anti-fouling toxins to leach through normally. Field tests in Barnegat Bay, New Jersey, and the Gulf of Mexico have shown no evidence of fouling after six months.

Static immersion tests conducted by an independent marine laboratory in the Miami area showed that the Sea-Slide Formula extended the life of all anti-fouling paints tested. This is because the Sea-Slide coating protected the bottom paint from premature release.

Tank test conducted by the Ocean Engineering Department of the University of Rhode Island using electronic measurement apparatus demonstrated that the Sea-Slide coating applied over anti-fouling paint was of “a clearly measurable value“, reducing hydrodynamic drag between 8% and 14% in separate tests with both a displacement hull and a planning hull. This confirmed previous tow force tests that showed that with the Sea-Slide coating, significantly less force was required to tow a weighted boat through water.

Using Sea-Slide Formula over
anti-fouling bottom paints

It is generally understood that certain active ingredients in marine anti-fouling paints, such as TBT, have been deemed hazardous to marine life.

The Sea-Slide Formula coating acts to moderate the initial surge of toxicants of anti-fouling bottom paints, which may cause certain environmental problems. The Sea-Slide coating allows anti-fouling toxins to diffuse through normally. A Florida test performed by a marine facility has shown that the Sea-Slide coating does not impair the initial effectiveness of copper or tin containing anti-fouling paints, and the useful lifetime of most paints are actually extended.

The Sea-Slide coating acts as a partial barrier, reducing the rate at which seawater exchanges at the paint surface. This slows the initial surge of toxin release and leaves a higher toxic level in the paint film for a longer effective life. The slow rate of water exchange in the Sea-Slide coating layer tends to concentrate toxins, sustaining a high level of fouling resistance.

The Sea-Slide coating can reduce biological fouling by being so slippery that most organisms are unable to make the protein bond to the watercraft’s coated surface.

Three Kawasaki 1100s were coated with Sea-Slide Formula with results below:
All tests were conducted during summer months on Barnaget Bay, New Jersey.
All tests were for one hour in duration (and are the averaged results of the 
3 Kawasaki 1100s subjects tested).

Note: 65+ means that they buried their speedometers!
Durability – all subjects reported that one Sea-Slide coating lasted greater than two weeks.
Subjects rated Ease of Application from Very Good to Excellent.
All subjects noted that when left in the water, their watercraft had substantial fouling when uncoated. 
When coated, minimum fouling was noticed, even when jet skis were left in the water for two weeks.
All subjects noted that they would definitely continue to use Sea-Slide Formula for their watercraft.

 

Boat racers have long known that “Hydrophobic” coatings, which are coatings that repel water because they contain silicone or wax, are not effective because they can actually produce greater drag in spite of their smoothness.

Sea-Slide Formula contains neither silicone nor wax, but is a “Hydrophilic” or is a water-absorption coating, which forms a water-to water interface, rather than hull to water.

For power-driven boats, a lower co-efficient of friction means increased speed, or lower RPM’s required to attain the same speed. For sailboats, the reduced drag produces higher speeds in lighter winds. For paddleboats, less effort is required to achieve the same distance and speed traveled.

The chief parameter for distinguishing between hydrophobic and hydrophilic surfaces is contact angle. This is the angle a droplet of water makes at the point of contact with a rigid solid surface. For hydrophobic coatings, this angle is always greater than 90 degrees, and it can be as high as 150 degrees. Hydrophilic coatings always have contact angles less than 90 degrees and usually less than 50 degrees.

A "perfect" hydrophilic surface would give a contact angle of zero degrees, that is, the water would sheet evenly over the surface. Although both types of coatings have relatively low coefficients of friction compared with common watercraft topcoats, hydrophilic coatings tend to be an order of magnitude more lubricious than hydrophobic coatings.

Water droplets contact and spread out more on a hydrophilic surface. Furthermore water can enter the pores of a hydrophilic material and totally wet it. Most natural materials are hydrophilic.