I am building a hp longboard and need to know where to place the fins. I have never done a quad before so I am a little lost right now. The board is 9'0" x 22"x 18" x 13 1/2". I am haveing trouble figuring out how far up to put them, how far apart and what angle they should be ser at, I am using probox so the cant is no problem.
Don’t let any one talk you into spreading the front fins too far from the back fins.I have a 9’6 longboard with a quad setup that is spread way to far(4" between fins from front of rears to back of front) and the board is horribly tracky and when you walk to the nose even in powerfull surf the fins popout and the board dumps you on your head.It rides great as a single fin though.
If you are using Probox and unsure about fin placement then buy the fins from Robyn Mair (handshaper on this forum). He will sell you the fins for normal cost, but also provide you with a pdf of your board’s tail with placement #s all drawn out.
Thanks for the link it looks like it will help
Looking to sort out quad LB set up.
Not afraid to try new ideas and research what is out there.
First confusion “does the McKee” set up really apply to LB?
Love Griffin’s set up any feedback???
Also throw in one of Todd’s here just to whip things up.
Just the facts mam, (Joe Friday)
I did one a few years back.
They go fast if you stay on the tail.
Sometimes a bit of side slip during bottom turns.
I set mine @ 7’ and 14.5" with a center box.
Ended up running fronts Large twin-fins and rears standard Tri’s.
Went back to 2+1.
Better all a round.
Hey Barry,
Respect your opinion. And Quads are not for all of us. Just soaking’ up info!
In my stupid opinion the Baron is plenty loose w/ dble wing swallow.
placement from rail has and other vitals noted and THANKZ ??? Why vary toe in, OPS only thinking LOL
This 9’0 HPLB is fast as hell, carves great, holds really well . Prefer the fin cluster moved up, this set-up at 16.5"/8.25", combined with a smooth continous rocker moves the turning/control sweet spot further up. Works perfect with EA’s front and rear.
Barry, Icc. Very much value and appreciate your input!
Aloha Nui!
Consider making it as a 5 fin with a center box so you have the 2+1 option as well…
good luck with the build!
Icc,
Thanks! And you mentioned continuous rocker, this guy is 8’-8" trying to take my “magic 9-0” (Clark foam on left) and replicate with some mod’s to outline and OPS never get the same tail rocker as “Mama” (gotta jig & try) but close tolerance US blank and no CNC here.
Also if you could devolve your toe ins and cants it would be insanely appreciated.
did you see this thread?
http://www.swaylocks.com/forums/who-here-riding-quad-longboard
here’s a couple more links that may be useful if you don’t mind digging a little to get answers…
Thanks young man!
Always a good idea to search the archives, and yeap reviewed that one and reposted the most relevant thread.
Links 1 & 2 cool but little info on my search although did snag this (rusty old gears are grinding thinkin this toe in is backwards) in the 70’s twins we ran stings “somewhere” past the nose.
OPS has been qustioning riders and checkin’ boards on any LB quad seen! U know in 81 OPS quit (shaping) rode others boards, so OPS missed out on the BS. Just couldn’t understand why some shapers (OLD) got so red in the face when OPS brought up B. McKee. In researching came accross this gem. Info is dated but the fundamentals are here. http://www.surfline.com/blogs/talking-design-the-board-blog-with-rusty-preisendorfer/rusty-looks-back-at-the-history-and-evolution-of-quads_38953/
So sorry now OPS get it! Really like Icc’s forward position, looks like 1/4" front 3/16" (HA) rear, my reg SB cants are 7 front 4 rear
OPS believes there is no need to repeat history or bad set ups also toe, cant and fins are just more shrapnel in the quad grenade!
Thanks again.
OK, well then, I’ll post up a few more blasts from the past, if they are of any use well and good, if not, move along until something more definitive shows up. I personally have not really delved into the quad placement mire, not too much anyway, just dabbled a little with bad enough results to know there are definite (if unknown to me) parameters that cannot be ignored with impunity LOL.
Before I get too carried away re-posting stuff, this is from this thread (page 2 of the first link), this whole thread is probably worth a read-thru if you’re doing a quad, anytime you have Probox Larry, Bruce McKee, and Robin Mair all posting in a thread on quads, well, you get my point… http://www.swaylocks.com/groups/quad-fin-placement-question
thanks oldphart surfer, I was directing the comments as much to the original poster as to you. A lot of these questions get asked over and over, and not everyone knows how to access the archives. The best way that I’ve found is to go to google or yahoo search, type in the phrase (like “longboard quad fins”) and then use the advanced search option to limit the search to swaylocks.com.
Here’s another from a different thread, (Bruce McKee, Lokbox, Bill Thrailkill, and Greg Griffin all weigh in on this one) http://www.swaylocks.com/groups/quad-fins-placement-question
Huck,
Truly grateful! Your aloha is great.
I’ve learned a lot since going to “the candy store”.
Gonna pull the trigger soon.
Mahalo Nui!
OK - here’s how the fins are placed on the 9’0 I posted a picture of. Was a bit off on fin placement. The board, which has a 13 3/4" tail, measures at:
Fronts at 16", front of box 2.5" from rail, rear of box at 1"
Rears at 8.5", front of box at 3.5", rear of box at 1.75"
This set-up obviously different from the McKee set-up, who sets his rear fins much closer to the stringer and much straighter. The shaper of this board, Art Coyler, former production and team shaper at Rusty (now shapes in Oregon and Japan), uses the Rusty formulas with his own tweaks. And that’s the thing about quads, so many ways to skin the same cat.
As stated earlier, I really like my fins forward. An eye opener for me 20 years ago was when Rusty shaped me a step-up and a semi for OB ( my paddle out for decades), in which the fin sets were both pushed and widened, which provided a much larger sweet spot for turning and driving, became the basis for all subsequent boards, from the mid length 5 fins I mostly ride to my HPLB’s. (on 2+1 HPLB’s, running the side fins at least 16" up really ‘shortens’ the rail line, gets me off the tail, and actually proivdes more leverage for turns and cut-back. When I ride an HPLB with the side fins closer to the tail, I feel like I’m now pivoting turns vs. the railing them that I prefer).
Here’s some words from Rusty on fin placement:
"Early on I took a fairly simplistic approach to it.
Early quads were an attempt to add drive and control to twins. In 1980/81, Twins were de rigueur. Since 1982/83, tri-fins were most surfers’ experiential basis. In my mind, I’m starting with a tri-fin. So I took the rear fin on a tri, and was theoretically splitting it in half. The more the rider wants the feel of a tri, the further back and closer together I’d keep the fins. If a rider was after more of a twin-fin feel, I’d move the rears towards the rail and the front fins.
My common middle ground: for argument’s sake, a 6’2" tri-fin has fronts at 11" and rears at 3 1/4". A lot of designers go half the distance on a quad, so that would put the rears at 5 1/2" and the same distance from the rail, about 1 1/8". In my humble opinion, I feel this is a little on the neutral side. I split the difference on distance from the tail (tri vs. quad: 2 1/4"), which would be 3 1/4" plus 1 1/8"…or 4 3/8". Easier math: 7’ board. Fins at 12" and 4" on a tri. Half the distance is 6". Split the difference, 5" for a quad. On average, I try to keep my rears about 2" in from the rail. That’s a generalization. It becomes a more complicated depending on tail width and board length.
Fin size: Fronts are similar to tri-fins, perhaps slightly smaller. Rears: profiles similar to fronts reduced approximately 10% in overall area. You can adjust drive by swapping out rears with different aspect ratios. More upright fins for tighter arcs. More rake to add length and draw to turns.
Foils: Your preference on fronts…your favorite tri fin fronts are a good starting point. If you are a fan of cambered fins – stay with them. If you prefer flat-sided fronts, you will probably like them in the trailers as well. Smaller, weaker surf; flats are probably the go as they react a little quicker and provide instant feedback. Bigger, more powerful surf – most prefer cambered or dual (full) foil trailers. Less prone to cavitate and let go. Some prefer full-foil trailers in everyday surf, citing more “feel”…smoother, cleaner, etc. Not as fast.
Cant on rears: Typically, I halve the angle of the fronts. It can vary according to intended use. Smaller softer surf; a little more cant will add some lift and looseness. Conversely, less tilt will increase speed, hold, and drive.
Nose vector (line towards nose): I typically point all four fins to approximately the same place, which depends on board length and type of surf the board is intended for.
Huge!
IF someone needs good information on LB or even SB quad set ups this thread has it all.
Thanks to all contributors present and future…
The stoke lives @Swaylocks
It seems to still come down to making your OWN mind up and going with it and no lookin’ back. Advance the sport
