Hi all…
well at first i am no expert on hydrodynamics aso…i was just thinking on putting sailkote on my hull rudder and keel…any suggestion…good or bad idea?
heres the link:
http://www.mclube.com/frames/sailkote/index.html
thanks
wis
if it isn’t broken, don’t fix it!
Ive used that on full size boats, i doubt it makes alot of difference, except you know its there!
If its not blowing it sucks!
if i know its there, then it makes a difference…in my mind[:-bigmouth]
thx anyway
wis
if it isn’t broken, don’t fix it!
I use it on rc spinnakers and it makes a measurable difference in the power required to pull a spin in to a tube–surely is slick…
Doug Lord
microsail.com
monofoiler.com
High Technology Sailing/Racing
Just a note… If you are racing in a class make sure the rules allow you to place something like McLube on it. (In some classes there has been much debate if it is legal or not)
Personal I love the stuff! I know others who will spray down their entire boat with the stuff (minus the deck). I think if you think you might want to use it for your boat go for it.
I use that stuff on my Nacra catamaran. I have an older boat, and the traveler car is pretty ancient, so spraying the Sailkote on it improves things greatly. I also use it on my blocks to keep them running smoothly. Great stuff–I haven’t ever thought of coating the boat with it though. It’s way too expensive and I’m way too cheap to do that! 0h–I use it to lube the rudder shaft on my Seawind with excellent results too.
Andy
Well I dont think it hurts you, I am pretty sure it doesnt help with speed on a boat of our sizes. The best thing it may do for you is give you a phsycological edge-pull it out and start spraying before the race, make sure the competition sees you do it and if they ask to try it say-I am all out. It gets them thinking about other stuff than sailing. In reality-I think it will keep general pond gunk off the boat and make it easier to clean, if you sail in salt water it will probably keep the salty residue to a minimum too but I dont think it will give you an edge-maybe good to spray on the running sheets and such too to keep them clean a lubed
Be very careful about using McLube/Sailkoat. It leaves behind a residue that over time can clog very small parts such as are used on r/c boats. (For example, I understand that the AC boats use silicon grease and light oil on their winches.) As to using it on your hull, like rain-x and wax it will likely make you slower rather than faster.
making it slower…could you explain a bit here…i do not have any ideas about hydrodynamics yet…i am still looking for a beginners guide on the net…couldnt find anything goog yet
thx
wis
if it isn’t broken, don’t fix it!
Look at the discussions about “rain-x”. Basically, any coating that repells water is slower than a finish that retains a boundary coating of water on the hull. For a full explaination try Marquai’s Aerohydrodynamics of Sailing.
Team McLube is NOT in the same category as rain X, Teflon or wax. It dries to a slick hard non porus surface and when used on hulls has a major benefit, according to Team McLube, of keeping the hull clean by being so slick that pond scum etc can’t adhere to it.
Further they recommend it on fins and rudders since it will:"… help maintain laminar flow."
Information from the source of the material is likely to be the most accurate of the info found on this forum coupled with the first hand experience of those using it…
Doug Lord
microsail.com
monofoiler.com
High Technology Sailing/Racing
Doug,
thanks for the info, exactly what i needed to know[:D]
have a nice day
Wis
if it isn’t broken, don’t fix it!
btw the Author’s name is C.A. Marchaj[:D]
just for info
Wis
if it isn’t broken, don’t fix it!
hi
which would you recommend:
Sail Performance
or
Sail Performance: Designs and Techniques to Maximize Sail Power
both written by C. A. Marchaj
Wis
PS dont tell me both[:-angel]
if it isn’t broken, don’t fix it!
Experience and experimentation is always a good judge of a product as opposed to company promotional materials. So a few simple facts. A “slick hard surface” is exactly what you do not want on a hull. Again, see the discussion about rain-x. The geneally accepted theory of lowest friction on a boat hull. is to cause a microscopic layer of water to bind to the hull since the drag between water and water is lower than the drag between wax, teflon, or any other “hard slick surface”. As to “maintaining laminar flow” over keels and rudders, the issues are very different for each appendage; there is some very good high level research that says flow over a rudder should be turbulent (look at a few of the recent turbulator experiments) and that at model boat sizes flow over fins is virtually always laminar. As to the issue of “pond scum” on model boats, I am not aware of too many r/c boats stored in water that develop “scum” problems.
I know a great many participants at the highest levels of sailing (example, Olympic Star boats and the America’s Cup) and am very famililar with experiments on bottom coatings for boats. While many of them use Sailkote on sails and in cetain equipment for lubrication purposes, no one I am aware of uses it on their hull or appendages. Also at the recent IOM World Championships (the largest r/c sailboat race in the World) I am not aware of a single competitor who coated their boat or appendages with Sailkoat. If you like, try the experiment yourself, put two identical boats side by side, properly wet sand one and coat the other with Sailkoat. I predict that the properly sanded boat will be faster, but of course, you always have the choice to follow the information Doug has provided from his close reading of the McLube/Sailkoat can (lol).
Finally, as to the Marchaj books, the two you have referenced are likely different editions of the same book–the book you want to buy is “Aero Hydrodynamics of Sailing”; it is the “bible” of sailing theory books.
Marchaj is great but a more up to date text that includes tips on hull and foil preparation is Frank Bethwaites “High Performance Sailing”.
And now back to Sailkote: Among the derisive comments made about the material was the dismissal of what I reported earlier as “company promotional material”; so here at great inconvenience to my fingers are some comments from people who must not be Roy’s friends:
1)" We coated the entire hull with Sailkote prior to the Volvo/Whitbred start. We checked the hull and sponged it off at each stopover ,and more than 15000 miles later in Auckland ,NZ did we feel it was time to recoat the hull and blades.That one recoating lasted us all the way to the finish." James Carrington , crew of Silk Cut Whitbred /Volvo 60.
2)-“If we had it to do over again we would go without any bottom paint at all and just use Sailkote.” Jez Fanstone,crew Silk Cut
3)“What a huge difference! We Sailkote our rudder and centerboard regularly so the kelp and weeds don’t stay on the blades while we’re racing…” Howie Hamlin/Mick Mortin, 505 Class Champions
4)John Marshall: HULL of Young America coated ENTIRELY in 95 AC
5)" We spray Sailkote on our hulls, centerboards and nearly every piece of equipment that moves". Pease and Jay Glaser, Olympic Tornado
6) “We Sailkoted the hull of the Dragon but not the rudder. The boat was in the water for 5 days (racing during the days and dormant during nights)
When we hauled the boat to clean prior to the European Championship the hull was clean but the the rudder was covered in a brown/green slime that precedes grassy growth they tend to get here…” (he won the Dragon Europeans ) Ron Rosenberg, 5 time world Champion sailor…lol
Doug Lord
microsail.com
monofoiler.com
High Technology Sailing/Racing
I saw the Farr 52 Bear of Britain hauled out half way through cowes week getting the sailkote treatment, also alot of good dingy sailors i know use it. Personally I can’t see it make a hell of alot of difference over a well buffed hull, but i guess the finish lasts longer than a buffed one.
If its not blowing it sucks!
Doug: Wasn’t the source of the quotes you typed from Sailkoat’s promotional materials? And Young America lost the 95 trials and the winner (Stars and Stripes as well as the winner of the Whitbread/Volvo races) didn’t fully coat their hulls with Sailkoat. But as I said the proof is in the testing. What races have you won and experienced superior boat speed having used Sailkoat on your hull?
Finally, I’m still not aware of any r/c boats that experience problems with “pond scum” or “slime”.
thanks for the info…now i got my xmas present[:-angel] thanks santa[:D]
sailkote or not??well i ll get some and try…anyway nothing to do during winter…way too much snow…last year we had 3 meters in the village…so sailing on snow…kind of hard…so reading time
thanks
wis
if it isn’t broken, don’t fix it!
Along with the tributes by actual users of Team McLube from the sailingproshop website I have one more: A couple years ago Dennis Conner, Bill Trenkle and I discussed a model project so I thought I would write Bill about the stuff.
He replied just now saying that Dennis Conner coats the hull and appendages of his Etchells with Sailkote and that the major benefit they saw(and are certain of) was that it kept the hull super clean.
Interestingly, he says they did not coat Stars and Stripes because the rules prohibited it which raises a question: John Marshall said they DID coat Young America!!
Doug Lord
microsail.com
monofoiler.com
High Technology Sailing/Racing