I'm hoping someone can enlighten me a bit on some fin questions. I'll break the questions down to accompany the pics - its always easier to answer questions when there are pics to go with them!
This is a picture of some quad fins I bought awhile back. The front fins are a bit bigger than the back fins, and the back fins are identical to some sidebite fins I have. The questions:
When would you use a quad setup with all four fins the same size, and when would you use a quad setup where the back fins are smaller? (Any general information, however subjective, is appreciated.)
In most quad setups where the backs are smaller, are they typically the same size as sidebite fins? (in other words, can you just substitute sidebite fins for quad back-fins?)
Do longboard quads use bigger fins than shortboard quads?
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This is a pic of some standard thruster fins. My question here is,
Do longboard thrusters or midsize thrusters require bigger fins than a shortboard thruster, in the same way that a longboard single fin would be larger than a shortboard single fin?
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This is a pic of the fins that came with this particular board when I got it. The two front fins are larger than my thruster fins, and the back fin is very small, like a side-bite fin (except double-foiled, of course). Almost like a "twin with back bite", the reverse of "single with side bites".
What is this setup called, and how does it differ, performance wise, from a standard thruster? (edited to add - I recently came across the expression "twin with trailer", which seems the most likely description of this setup)
The board is called a "convertible", does that mean it is meant to be ridden as shown, or with the option of being ridden as a twin?
again, opinions and subjective observations are welcome
I’ve always preferred 4" to 4 1’4 rear fins on a standard shortboard. I’ve never liked sidebite sized rears. I’m a big guy so I’m sure that makes a difference
I've always preferred 4" to 4 1'4 rear fins on a standard shortboard. I've never liked sidebite sized rears. I'm a big guy so I'm sure that makes a difference
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Thanks for the response!
So, are you saying you prefer your quad fins to be all the same size, vs smaller fins in back? Does this make the board drive-ier? More power out of turns? Tracks more positive, less "squirrelly"?
Can’t really answer the fin size question, because rocker and rails are more improtant than length. Flatter rocker, Thicker rails needs less fin than heavy rocker and thin rails for same effect.
Wing changes rail line even more.
It is all about what part of the board does what in a turn. ( I know that makes no sense, but can’t explain it better). Do you carve off the front foot or slide off the back foot? Surfer style, and fitting the board to match. That’s magic.
Myself, I turn off my front foot, so I like more rocker up front, and bigger fins to keep the unweighted tail from sliding out. A back legged surfer wants less entry rocker, because he isn’t using it to turn with, and it would just slow him down. And smaller fins because he is weighting the tail, so the back rails will bite in more, so he can get away with smaller fins.
My best advice is to try every option you have. I use smaller rear fins on the quads. I also use smaller fins in general on the quads. The only exception are the fins I got from Robin Mair that are large.
If the quads feel too loose with small fins in the rear, I just add larger fins and it fixed that.
With the thruster setup, I usually use 3 of the same fins. But I have several boards with with the long single fin center box and I only have 2 small fins. I usually use what I have for those.
Hey Huck , here’s my semi ignorant layman’s understanding of quads- you take the center fin of the thruster and split it in half and move the halves towards the rail where they are more engaged when turning. With this pholosophy the rears will be smaller than the fronts (basically half the area of a thruster rear, although I think in practice they are more than half the area).
Now another big variable you didn’t mention is how far off the rail to place the fins. The McKee set up is closer to the center and thus surfs more like a thruster. The other option is to move the rears closer to the rail, like a thruster and then the ride becomes more like a twin, but drivier.
But don’t liksten to what I’ve said, because I have found I don’t like quads, at least not the ones I’ve tried.
Twinzer…another story. I’m more stoked on my new twinzer than I have been on anyboard in the last ten years.
ps are you thinking of adding the rears to the board in the pic? Consider using Four Way Fin System for max adjustability. The only negative of 4wfs is the fins are not interchangeable with FCS.
pps one last thing, I’m a believer that in bigger waves you need less fin, as long as it is not really choppy. The faster you go (big waves) the more pressure exerted on a fin so the less area needed.
Not looking for specifics about my surfing style, or fin placement and cant, etc. - just looking for generalities to fill in some blanks in my understanding of fins. When I ordered my first quad fin setup, the back fins I received were just sidebites. I was a bit disappointed, and wondered if this was industry standard, or if I just purchased a cheapie set for the unsuspecting LOL.
I was also suprised there were no "longboard thruster fins" or "longboard quad fins" - when there are single fins that are clearly designed and marketed for longboard use. Leading me to wonder, do longboard thrusters and longboard quads use the same size fins as shortboard thrusters and shortboard quads?
The twin with trailer setup is something I rarely encounter - is it a setup that has largely been abandoned? I do sometimes see a little trailer fin show up in some quads, and John Cherry uses them in his Simmons style twin keels. But almost never in the configuration shown in my photo. Really don't see many twin fin setups either - are they unpopular for some reason?
I know what a convertible board is, with 5-fin options. But the board shown had only 3 fin options, and was labelled a covertible. So I have to assume one of the options was to be ridden as a twin. I don't see many twins like that, which is why I was asking here, just to get a bit more insight.
I realize this is just basic stuff for most, but as I have pursued a better understanding of surfboard design over the past few years that I've been building my own boards, my understanding of fins and fin setups has lagged.
About me. I"m 6’4", 200 lbs and I ride all quads and have about 15 different fin options.
Question 1 to 4 -
When would you use a quad setup with all four fins the same size, and when would you use a quad setup where the back fins are smaller? (Any general information, however subjective, is appreciated.
In most quad setups where the backs are smaller, are they typically the same size as sidebite fins? (in other words, can you just substitute sidebite fins for quad back-fins?)
Do longboard quads use bigger fins than shortboard quads?
1) I never use quads with all the same size fins! It will ride way to stiff. Even my Simon Anderson quad set made for big guys the front fins are about 1/2" taller and I use them on a 9'2" gun. I use the composit Vector fin set most of the time and as a rule I use the 3.75" rear fins in most conditions on most of my board. If the waves are smaller or guttless I go to the 3.40" rear quads, and on the rare occation when the waves are big hollow and criticle I use the 4.0 rear quad fins. Front fins in quads are usually about the same size as any thruster fin set so you can use any front fins you want. The real turning peformance and ride adjustability comes from the back fins... shape and size.
#2) Quad rears are not always the same as side bites but some side bite fins would still work. Alothugh most side bite fins are side foiled and most quad sets rear fins are double foiled so there is a difference in ride when using side foiled fins in the rear. Not better or worse just different. Quad rears like side bites come in many sizes and shapes and are all open to be tested out by you.
#3 & #4) If you look at most quad fins for sale you will see they have a rider weight rating and not a board size rating. I don't follow their suggestions and I ride all of them depending on what performance I'm looking for. Smaller fins for loose, bigger fins for stiff. This goes for any board your ridding. longboard or shortboard. Single fins are different since there is only one fin, but you will see guys with smaller fins in their longboard when its very small and bigger fins in their shortboards when it's big. Think about the performance you want out of your fins more than the appropreate fin size based on board size. There is no one perfect all around fin set up for any board, especially quads.
Quastions 5 & 6 -
What is this setup called, and how does it differ, performance wise, from a standard thruster? (edited to add - I recently came across the expression "twin with trailer", which seems the most likely description of this setup)
The board is called a "convertible", does that mean it is meant to be ridden as shown, or with the option of being ridden as a twin?
5) I call it a twin with a trailer. Bigger the side fins, smaller the back fin. With this setup your playing around in the area betweet a twin and a thruster. Good for quick turning and a smaller turning radius. I use this setup in smaller fast waves that need quick pumps without any need for long drawn out power drives. Can slip out if you push to hard on bottom turns unlike a quad or thruster so this setup is better in gutless waves. 6)The convertable tag most likely means twin with trailer or thruster since twin fins usually have the fins in a different spot than a thruster or a quad where the front fins are in roughly the same spot.
Again, to me quad performance is all about back fin size, shape and placment. Check out Bruce McKees website for a great explination on the modern day quad and all it's options.
http://www.mckeesurf.com/brucemckee/quattro.htm
Start with the Mission Quattro page in the link above but be sure to check out the whole site for all the info and fin placment tables provided by Bruce.
I'll add this - Kinda what llilibel03 said, I love my 4wfs boxes as I can get lots of different cant adjustments, some toe, and a little fore/aft (I wish I could get a little more, but having first switched to quads with RedX boxes, I found the amount of distance between fins I wanted.) Also, I find I prefer an asymetrical fin set up, makes a huge difference for me.
I use smaller fins in the back, and, as you may have noticed from my pictures, I like less rake in the rears to help facilitate tighter radius turns. On my biggest gun I use double foiled back fins which are larger than the back fins I use in my other boards - I'll take all the drive I can.
I've yet to try smaller in the front and bigger in the rear.
my 2 cents (euro); wide base for hold, narrow tip for loseness. thruster i find stiffish and predictable, quad is very lively (a la robin mair). you have great skills huck, buy a sheet of birch ply, make a shit load of various fins… see who is talking bollox! keep up the good work, big up from the west of ireland…
I think of it this way… The further back the rear fin, the less fin you need. So if your rears are close to the fronts, you can get away with more fin in the rears, and (depending on placement and where you put your back foot) get a very pivoty, “lively” feeling with added hold and drive when compared to a thruster. If you fins are way back, you can use less fin… those rear fins are out on a longer lever. The further back they get to the trailer on a thruster, the closer in fin area and base you want to get to the total fin area and base on a single trailer fin.
Others may disagree, but this is what works for me. I should say that my back foot is generally over my front fins. Guys who put their back foot way back over the trailer might see things differently.
I rode the McKee setup on a bunch of boards for years, and liked it. I rode slightly bigger front fin that rear. Now I’m using the “Robin” setup and prefer my fins much closer to the same size. That’s where I get my line of logic from.
I ride the twin with trailer setup, although recently I’ve just been riding that board as a twin. I’ve got the futures t1 setup. I’ve started riding twin fins a lot recently. The trailer, at least for me, takes out a bit of the pivot without moving thing twins do. I feel like a thruster will want to draw an arc, but twin will just pivot and not necessarily make an arc. Obviously thrusters do that too, but less. The little fin keeps the pivoty-ness but adds some hold, so it doesn’t feel too thruster like. In smaller summer waves I was just like I don’t need the little fin and I got hooked on the twin setup. Depends how you surf really. I’m not sure if this fin setup was intended to be used with the trailer but it’s fun as a twin, and that’s good enough for me.
Cant was 6* front 4* rear with some concave through the fins… Board sucked. wouldn’t turn.
Increased the cant to 8* and 6*. Board went better.
Increased cant to 8* and 8*. Board went better but, backside bottom turns to verticle were difficult.
Added 2 more rear boxes out by the rail. Like 1" off the rail. Backside bottom turns to verticle problem fixed.
Switched to the Belik High Aspect fins. Everything went better in surf less than overhead.
Built another board with Griffin’s 5 fin setup (as best I could) and never looked back at quads.
The 5 fin does everything the quad did for me and more. The speed and section beating is still there but, it’s got that center fin stability and pivot.
Happy camper. Next board will be a twin. Just to try something new.
...Built another board with Griffin's 5 fin setup (as best I could) and never looked back at quads.
The 5 fin does everything the quad did *for me* and more. The speed and section beating is still there but, it's got that center fin stability and pivot.
Happy camper.
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Cool, thanks for sharing your experience - got any pics of the board? Did you use Griffin fins, make your own, or purchase over the counter fins? Flat bottom ala Griffin?
I’ll take some pics. I started out using the Belik High aspect fins in the quad positions with a GT center fin. (it’s all I had). It went ok. Then, Keith Melville gave me some small G10 thruster fins that I plugged into the rear 3 spots. So, now, I had the front Beliks with 3 g10 rears. Went much better. I think I had too much fin area before. Then I finally found a true set of Griffing 5 fins. Everything goes better. The board is 6’0" x 19" x 2 1/2" ish, flat bottom, hard tucked edge. I messed up on the rails near the tail tho. I tucked them too far. I’m hoping to fix that within the next month. I plan to build up some more resin on the tail rail and make the rail less tucked there. Initially, I went a little overboard with the whole “hard tucke edge the whole length of the board” thing. I’ve since softened the forward rails and it goes better still. Still a tucked edge but just not as sharp. It’s got lowish rocker and goes prett well in everything from waist to overhead. Although, if it’s under chest high AND mushy I can’t get it to go. It needs some steepness to the face if it’s that small… The template I patterened after this board (with Robin’s permission): http://www.mairsurfboards.com/pages/design_portfolio/shortboards.html … The blank was a Marko 2lb. 6’2"R I believe?.. I did not intentionally alter the rocker… And, I left some late '80’s / early (pre-slater) '90’s volume in it…
To clarify, I’m CERTAIN I could get a better board or boards from known builders that work better than my boards. Even when I have gotten my boards “dialed” for me, they are still jalopies. But, if I would have just bought boards, I would not have learned nearly as much about surfboards and what I like in a surfboard as I have. Plus, I like building 'em… Hahaha, I guess that’s preaching to the choir though.
