Measuring Kneeboards.....?????

[quadfin]

Better Pic of the board...my daughter holding the board.

[Beeline2.0]

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[red]

Quad,
Board looks good. My estimate is that you surf down the line stuff, with nary a pause for breath. How does it cut back? Full rail turn or do you have to sit on your feet a bit?

[hart]

Quadfin, you are living up to your name..it's a mean outline Mate, looks really quick.Looks like a classic 4 fin with down the line speed, yet you could break the tail anytime you want.

Beeline, you're right, although Horan did continue with success with Geoff McCoy's lazer zaps into the mid 80's (but only with Ben Lexon's winged single fins) cause they gave the single fin concept drive (and remember what Lexon did in the America's Cup), it was when Simon Ando one the Coke and Bells in the one year (1983) that changed contemporary surfing forever. The Thruster was well and truly born.

Keep surfing guys and regards from OZ.

[quadfin]

The board is definitely a perpetual motion machine. On large waves I actually pump my way to the bottom to build up speed. With the "no nose" I don't catch water on the pumps, increasing my speed down the line.

The board rides surprising well in mush since it takes such a high line. Our waves here in the summer are tradewind swells without much punch. In Hurricane Season and Winter they are different animals...very much down the line, and this board rides them all. Cutbacks are just a thought away.

I think the "lazer" design is more applicable to KB because of the difference in the rotation over a center of gravity between a parallel and square stance. I can understand that this board would not work for a KB with much parallel in the stance. Pulled out an old Romo single fin a many years ago when Horan was playing with that design just to check the diff. Definitely a skill check for use of rails and controlled slides, but she tended to tube ride deeper and longer for some reason. ?

Thanks for the feedback. Planning a new board and always looking for improvements.

[Beeline2.0]

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[hart]

Quadfin, please pardon my ignorance, but where is St Maarten?
Your comments about your outline all make sense and I guess the lack of nose area is contributing to the depth you're achieving in barrells..You must get good waves...imagine the opportunity to design your equipment purely for tubes.
You talk about parallel stance..what do you mean and where is your knee position? Are you back behind halfway and if so, how much?
Beeline,you are right..Simon won the Coke and Bells in 1981..I just checked, but I must let you know that he has never won a World Title despite his strong presence on the tour in all the years that he competed.
Good to talk to you guys and thanks for the responses.

The land of OZ

[quadfin]

St. Maarten/St. Martin is a pretty unique place. An Island in the Caribbean 200 miles SSE of Puerto Rico. Dutch on one side and French on the other with no borders. We get our waves primarily in the winter when cold low pressure areas move through North America. The colder it is in New York the better our waves here. Almost all the breaks here are coral/lava reefs. We also get some very well heeled tourists here in the winter and the lagoon (volcano crater!) in the middle of the island is stuffed with mega yachts and movie stars. St. Barths, Saba, St. Eustatius and Anguilla are all within site of the island.

What I meant by stance is side-by-side knees across the board, eyeballs looking ahead. With knees on both rails you can transfer weight a lot quicker to the rail on a wide board than a standup who has to use upper body weight shift and a push/pull with his legs to turn. Just my theory but I know I can turn inside most standups. I would assume that a KB that places his knees at some angle to the rails would turn quicker on a slimmer board. Again, my theory. I ride my board back from center with COG over fins. That is why fins are not any more forward.

Checked the Specs for the 1980 McCoy/Horan Lazor Zap and it was an interesting comparison. The LZ was at 20.5 and I am at 23.75. The LZ was 5'6" mine 5'8". Big diffs are that the KB wide point is way back from the LZ , KB has less tail kick and equal nose kick to LZ, I assume big diff in rails, and the big diff...thickness and board volume.

I am enjoying the board design discussions, best yet on this site.

[Beeline2.0]

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[Beeline2.0]

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[hart]

Quadfin, what a unique sounding place! Your equipment is making more sense with every minute..you are right about the way kneeboarders turn, we have the potential to create far more powerful hook-type turns than standups. Look at the way Farrer gauges out a top turn..power is full on, no energy wasted through bodymovement or transferral of weight from front to back foot.
And just while we're picturing an upside down top turn, have you seen what standups are doing to their rails for the first 8" up from their tails? They are dead square and blocky...hardedge under, but all block. The complete opposite of say a flextail..a board whos rail reduces to zero.
Standup boards wont now do the type of top turn Farrer does because they either want their tails to break (into something like a floater) or release completely and get air. Or some kind of tail slide generated from an extended back foot....not the most powerful of maneouvres.
Kneeboards will always be kneeboards, look and learn from our more marketable brothers, but keep the drive to us!
Beeline, what bullshit photos..do you recall the amount of volume in McCoy's boards? Full-on. Cheyne was an earlyTom Carroll in a way due to his lower body strength ,very powerful from the waist down...was probably also the reason he could get single fins to perform so well.
Talk again soon.

[quadfin]

Interesting photos. The dimensions that I had pulled off the net was for the Rip Curl below which had a wide point slightly rear of center. The LZ2 board seems to have the wide point moved back.

My shaper and I built my board based on measurements from my center point only. The criteria for the front half of the board was how far forward I could shift my weight and from there to pull in and the back half of the board to just stop at the end of my fins, all within a 5'8" frame with as much width as he could get out of the blank. We used no template or design as a model and we committed to build it by measurement no matter how ugly the lines looked or how the measurements contradicted our pre conceived ideas of what it should look like. That is kind of how I got into this forum "kneeboard measurement".

The fin placement was from the Aussie concept of putting the fins under or slightly rear of COG. The trailing fins are something I have used since surfing in a contest at Blacks in 1989 and meeting a KB that built, I believe "Primitive" or something close to that, boards. I am sure you guys in Cali know him.

Again, my board has NO volume. The deck is concaved and the board razor thin. Somewhere North of a Greenough Spoon and South of a Romo. Sitting in the water I count on the reflection off my shiny white legs to ward off sharks I sit so deep.

[DavidW]

Quadfin, the guy you talked to at that Blacks contest was Eric Schoelkopf. He used to shape under the Primitive label. And some of his boards were very primitive at that time. However, now he makes great boards for some of the best kneeboarders in San Diego and So. Cal.
Anyone who want to conact Eric, who is computer challenged, his Ph# is 760-941-8339.

[quadfin]

That's the guy! I remember him being fired up about his board designs. I remember thinking that his trailing fins on the tail with the Aussie setup might be the missing gap between the Tri and the Quad. I use the exact same fin setup on my 6"0" Pintail Gun as the 5"8" pictured, but with front fins cambered out more and longer trailing fins.

Any chance of posting a pic of Eric's current designs?

[hart]

Quadfin,

Hearing you guys talk about the Aussie fin style and stuff is a trip!..I guess I know no different, so it's all of interest.

The fins of all my shortboards have one common thread. I saw a coincidence happening a while ago and I've not been game to shake it. Not that I'm superstitious (but I am), remember I am a kneeboarder...The trailing edge of my rail fins was pushing 17'' up from the tail for quite some time. With tail widths hovering around 18.5"+, my rail fins began placing themselves exactly 17" apart! The perfect triangle. I think.

Watch out for the sharkbait.