Howzit fellow swaylocks brothers, Need some info on fin placement for a quad gun that's a 8'6". Aloha,Kokua
Hey Kokua, McKee has been spending lots of time on quads, so try his site, you have some info at the top of this link: McKee
Those photos were taken like 6 or 7 years back, and he was already obsesed with quads, so go figure, the guy made some R&D.
Coque.
Hey Kokua,
Set the lead fins the same way you would a thruster. The trailers generally go about 6.0" from the tail end and about 2.0" in from the rail. If you want the board to be more directionally stable place the trailers more aft and toward the center. More forward and toward the rail will give the board more snap and make it looser. Placement will have much to do with how wide the tail is and how it’s configured. More engaged tails want the fins further apart and more forward for obvious reasons.
If you going to use FCS system. cant the lead fins at 7 degrees and the trailers at 2 degrees.
Aiming the lead fins a 1/2" outside of the center of the tip of the nose and the trailers the same place makes for a nice graduated toe in which works very nicely.
Mahalo, Rich
Hi Coque ,
Any idea wat’s the fin placement for board size 5’6" x 20" x 2.5" , nose 16" , tail 16" , tip to tip 11.5" , depth 4.5" .
I’m using fcs GX (the small side fin for longboard) n G5 fin system … .
Thanks . Andi .
Hi Andi,
ALL the info you want is on McKee’s website, there are a few excel file that have this information for ANY board you want, can’t give you the shortcut, you will end up on the home page. McKee is very specific about the placements…
W
Andi, as Wouter said, all the info is on that link, i could put here the archives, but i think that if McKee makes public all his knowledge, at least we should visit his site:
Coque.
Thanks for the site, Coque. Interesting stuff…
Why sometimes single foiled trailers & sometimes double foiled, I wonder…
And this one almost looks like the red is single & the black is double.
I’m sure there are good reasons for all that, but I’d love to hear his own theories behind them…
The foiled inside edge on rear fins acts just like a stabilizer center thruster fin only positioned out closer to the rail. Single foiled rear quad fins seem to be too erratic.
In my little experience:
Asymmetricaly folied trailers: more lift, more projection, more drive, tighter turns, good for beach breaks
Symmetricaly foiled trailers: more neutral feel closer to a thruster (i think that’s why stock quad set ups have symmetricaly foiled trailers), easy rail to rail, smoother feeling.
Anyway i think moving trailer fins closer or farther from rail and changing it’s cant/toe makes the biggest difference.
Coque.
RichardL from Lap Extreme was telling me a pretty cool way to find fin placements.
You multiply the length by .050 for pretty much most boards. You drop the multiple down to .048 for a drivier board.
Im pretty sure you find the length from a quad by just measuring the board out to the rail. Even if you dont use the measurement, it would be interesting to measure your boards and see how spot on the measurement is…
Maybe Richard can chime in hear and elaborate more…
…very bad idea put a double and a single foiled fin together…
the water is not that complicated when run through the bottom
so complicate the stuff is a silly thing
too much turbulence occurs
Quote:
Hey Kokua,Set the lead fins the same way you would a thruster. The trailers generally go about 6.0" from the tail end and about 2.0" in from the rail. If you want the board to be more directionally stable place the trailers more aft and toward the center. More forward and toward the rail will give the board more snap and make it looser. Placement will have much to do with how wide the tail is and how it’s configured. More engaged tails want the fins further apart and more forward for obvious reasons.
If you going to use FCS system. cant the lead fins at 7 degrees and the trailers at 2 degrees.
Aiming the lead fins a 1/2" outside of the center of the tip of the nose and the trailers the same place makes for a nice graduated toe in which works very nicely.
Mahalo, Rich
I had a great 8’6" thruster gun the front fins were at 13", rear at 5"
HTH
Quote:
…very bad idea put a double and a single foiled fin together…
the water is not that complicated when run through the bottom
so complicate the stuff is a silly thing
too much turbulence occurs
Well, looks like most profesional shapers and profesional surfers think just the opposite and they spend some time on R&D…
I can say i feel the difference and most of the times i like symmetricaly foiled trailers and asymmetriccaly foiled front fins.
Just an oppinion.
Howzit Kokua my old friend.Seems to me like if its a gun you want to go fast.Putting all of those fins on create a lot of drag eh?? RB
Quote:
…very bad idea put a double and a single foiled fin together…
If you look at mckee setup they are really not all that much together. I really doubt (as someone also pointed out to me in another thread) that there are any waterflow directed from the front fins to the rear fins with the quad setups, the fins are too far apart.
regards,
Håvard
Howzit Mr. Clean, Actually the info is for a shaper friend who is making the board for himself and lately he’s been into quads. So how are you doing these days? Aloha,Kokua
Dear Wouter & Coque ,
Can’t find any fin placement on the page , maybe can enlighten me a li’l ?
Sorry for the trouble …
With respect ,
Andi .
Have a look at the menu on the right hand side of the home page
look at quattro!