Does anyone have any ideas on how cutous work? Any thoughts as to what the designers at RRD were thinking when they created this design?
By reducing wetted surface in the tail, they reduce lift in the tail allowing the nose to ride higher, which you want in a shorter board. Too much lift in the tail and the nose is going to pitch fwd. So on large wide short boards one advantage is better trim while sailing, to compensate for the extra life in the tail. Think that also helps gybing on wider tail boards. There's more to it though.
I used cutouts on an older style longer thinner board and ruined the sailing trim of the board. Made it crap in chop.
"I used cutouts on an older style longer thinner board and ruined the sailing trim of the board. Made it crap in chop. "
Thats weird as cut outs on my narrow speedboard made it trim better and handle the chop[}:)]
These particular ones seem to be radically longer than most I've seen, to the point where it may be more than just the tail lift. I know wetted surface has been well discessed b4 but maybe these are heading down the reduced wetted areea path
Have you seen Plug 'n' Play 2 they explain it for you, i'll give you their theory.
The cut outs are there to allow the tail of the board to sit deeper in the water so you have more control at speed over choppy water.
Antoine or could be Finian not sure, shows his board with plates you can remove, or add, to allow how much tail sits in the water (and nose out the water), he explains that it changes the trim angle of the board and give it a larger wind range, with the desired depth of the cut outs..
Since it’s not windy here (Canberra) at the moment, I have time to post to this.
These are pictures of the cutouts on my board, as well as the sticker that says the board has a “Carbon T-stringer”. The board is a Fanatic Sting Ray 150TT. The cutouts and carbon T-stringer were both developed by the Marketing Division of the Fanatic Sailboard Company.
This is a simple explanation as to how the cutouts work: They are red, and they have flames coming out of them, so they are fast. It follows that if the cutouts are fast, the rest of the board must also be fast. As people sail up behind me, they call out “Hey, Bristol, I like your cutouts, they’re fast!” I would like to call back, but they are generally well in front of me and out of earshot by the time I have thought of something to reply. I hope they don’t think I’m being superior, just because of the cutouts.
This is a technical explanation as to how the cutouts work: The board generates static electricity as it travels through the water. Static electricity travels along the carbon T-stringer to the cutouts. This static aligns the water particles in the same direction as the board is travelling, thus reducing drag on the fin, so the board travels more quickly, well, fast, actually. Surplus electrical energy is then discharged through the cutouts, generating flames.
I want to try and harness this surplus energy in an environmentally-sound way. I understand that I may be eligible for a Government rebate if I can discharge into the ACT grid. To that end, I plan to have Mrs Bristol sail the board in a thunderstorm. The carbon mast and alloy boom are both excellent conductors of electricity; I am not sure about Mrs Bristol’s conductivity. To the cutouts, I will attach a copper wire, which will then connect to the ACT grid. I believe that I need a special valve to stop the current flowing from the grid into Mrs Bristol. I must be sure to connect the valve the right way round.
I want any rebate money from my idea to go to the general good of the windsurfing community. Kiters, this idea is NOT for you. Your lot (Benjamin Franklin) tried this years ago, and did nothing further with it.
Did I mention that it’s not windy here at the moment? It hasn’t been windy for some time.
These are my cutouts and I view them as similar to the cutouts above because they start forward of the fin,which appears to be very affective at ventilating the base of the fin.
After every carve gybe the board gets sideways when you put the peddle down and the same when pinching upwind or accelerating - great practice of how to rectify a spin out though
I notice the new cutouts are generally well behind the fin and they might even be helpful..
Hey goo screw is that a Thommen board.
My experience with cutouts in front of the fin box is that it sucks weed onto the fin.
Ive ridden a Thommen with those exact cutouts and it was shocking when there was weed around. Did you ever experience this.
ta Vando
Yeah vando,thats the T1 Rs 60.I've never sailed it around much weed,the stuff you get at the Pit is like tiny string weed and normally washes off,although can be enough to devastate a fast run on the speed gear with an upright fin on the wrong day.
The way this board sucks air onto the fin would make me suspect what your talking about might be on the cards.
If it didn't have the cutouts I think it would be good for a 30 fin at Sandy,as it is it has been comfortable with an sr6b 36 and I just got an sr6b 34 for it hoping for a one hour board that will do 35 knots(big ask on a 34 fin though).
Maybe I didn't read all the threads but arent cutouts used for two reasons
1. To reduced wetted area of the planing surface.
2. Keep the deck the same size so you got somewhere to put your feet.
I think cutouts are useful as they allow you to attach the boom directly to the mast.
Otherwise you'd have to clamp it onto the luff sleeve.
Long live cutouts!
(Did I read the rest of the thread before posting? Sure I did!)
thats probably because Mrs Bristol appears to have become a past participle?! Currently battling with flames from the cutout zone....
Bristol - love your work man, v funny