Hydrophilic bottom coat = extra speed?

[Starscream]

I came across a review of a product called Hyspeedkote in an issue of Yachting World. It's a hydrophilic coating that comes in spray-cans and may be applied over bottom paint or directly on the hull. It apparently increases top speed, fuel economy and so on. Check out http://www.hyspeedkote.com to see how it works.

It looks like it's not available in the USA, probably regulatory issues. Does anyone know of a similar product available in the US? Have any of our European friends on this board tried this product? If it works, I am sure that every Mac owner would be happy to shell out 50 bucks or so to get an extra knot of boatspeed.

[extreem]

It looks like it's not available in the USA, probably regulatory issues. Does anyone know of a similar product available in the US? Have any of our European friends on this board tried this product? If it works, I am sure that every Mac owner would be happy to shell out 50 bucks or so to get an extra knot of boatspeed.

You can order directly from the website. Company is in Sarasota FL.

I haven't tried it, but let us know if you do. I would be interested in a little more speed.

[Kelly Hanson East]

Looks like you cant order online, only gives a toll-free number to order.....these guys need to get into the 1990s of retail at least...

Ill hawk on of my customer's interests here along these lines as information only (I dont have any financial interest here) - Telluride East Inc.

see

[Starscream]

Looks like you cant order online, only gives a toll-free number to order.....these guys need to get into the 1990s of retail at least...

Seems like they're looking for dealers, maybe Kelly Hanson Marine and/or BWY could pick them up

The science seems believable, I think I'll give it a try in the spring. I'll have to plan a good before/after experiment so that I can give real results.

[Currie]

It says it's a "magnet" for water. Is it also a magnet for slime, seaweed, barnacles and snails? Just wondering.

[Starscream]

Good point. The FAQ section says that it will "limit the paint's anti-fouling properties since HSK does not shed barnacles".

It doesn't seem like a high-risk thing to try though. Honestly I would have preferred to not be the guineau-pig, but I'll take one for the team in the spring if I can get the stuff delivered to Canada.

Anti-fouling's not a concern for me, since the boat lives on its trailer and plays in fresh water only. Starscream came with an anti-fouling coat which was apparently a necessity for operation in the western end of Lake Ontario, but it's not an issue for a Montreal based trailer sailor.

http://s854.photobucket.com/albums/ab10 ... c00473.jpg

[waternwaves]

something doesnt quite add up. increases surface tension and holds the water on the hull tighter.

a hydrophobic coating would repel/release water from the hull.

I suppose I could go calculate the reynolds number for the bumpy bottom surface of my boats, and since I know how fast it goes, I could approximate the shear per unit area of wetted hull. for a few simple sections.

But if you want to decrease drag, changes in the boundary layer (and assuming the boat shape does not change) generally have to allow the water to move faster. something that is not going to happen if it is held tighter to the hull. JMHO YMMV.

sliding the boat through trough of bubbles would probably have a much greater improvement, with a corresponding slight increase in dept of draw.

[Starscream]

Well, I'm not the right type of engineer (Project Management, so forgot most of my theoretical stuff) but if I understand correctly, a hydrophobic coating repels water and is essentially like dragging a dry object throught the water. The force required to do so would depend on how slippery the hydrophobic stuff is. A hydrophilic coating keeps the surface wet, potentiallyy giving the hull the same CoF as water on water.

I'm not trying to sell the stuff, and certainly realize the dangers of believing everything you read, but I figure that if it made Yachting World (sept 2009, p. 42 is a short article specifically on Hyspeedkote, and May 2009 has an article about hydrophilic coatings in general) then there just must be something to it. Maybe it's that possibliity of an extra knot that's blinding me!

[delevi]

Star,
An extra knot under sail is absolutely huge. I seriously doubt you would gain that much. The mere claim itself lends one to doubt. Every sailboat is different and the variables are nearly infinite i.e. boat, rigging gear, wind, sea state, etc. If you do gain 1 knot under power and 1/4 knot under sail, consider the product valid. I guess if the price is right and you aren't concerned with anti-fouling, no harm in trying. For those of us keeping their boats on the water, like myself, I wouldn't be so inclined. Would really look forward to see your results if you do try it out.

Happy 2010!
Leon

[waternwaves]

Its really pretty simple.....

a large hydrodynamic test tank can prove if the stuff works.

however........if you look at the USN research, University research, and all the other real sources out there out there there doesnt seem to be much success in the hundreds of materials tested.

There is considerable doubt that there is a measureable difference with most of these advertised products. Hard burnished smooth coatings have been tested in the tank and have a measureable basis.

Tests of extremely small differences in surface friction, done on a boat on open water, with fuel computers, gps etc....... may be good, but by no means certifiable and measureable to traceable standards\, and the presence of advertising and reviews in trade magazines is to sell product. (I have written such reviews).

there is testing for some materials, for example "www.chbmeng.ohio-state.edu/~brodkey/DR-surface.ppt" was an interesting attempt to get numbers on drag reduction.

The search will continue, but the speed increases claimed seem dubious at best.


call me old and slow........ but if it is not repeatable under controlled lab conditions.......then i generally take such claims with a bag of salt.

caveat emptor.

[bubba]

I guess if we wanted a racing sailboat we would have bought something like a tri-maran or catamaran but I guess even they are trying new products to get that extra 10 mph out of there multi-hulls. We have bottom paint on our M and it moors on the trailor and I have often thought of using some kind of wax on the bottom paint , has anyone tryed wax

[Kelly Hanson East]

I use wax only on the bottom of Catigale and have won every Edgartown race I have entered....Im selling the wax special this week only for 999 USD for a small can...the boat buck special.

Order now, supplies limited...

[bubba]

The way you say small can of wax it sounds like it may not cover the entire bottom of a Mac is that it ? How about std auto wax over bottom paint ?

[K9Kampers]

I use wax only on the bottom of Catigale and have won every Edgartown race I have entered....Im selling the wax special this week only for 999 USD for a small can...the boat buck special.

Order now, supplies limited...

Steph- Since they're small cans, I'll take two! Whuts yer price break...5 can minimum? I'll compare 'em against my own Whitehull Lightning formula!

Bubba - he does the small cans the way you buy a pack of eight buns to a pack of 12 hot dogs!

[dennisneal]

I've wanted to use Sex Wax, but my Admiral says: "No Way!"