i rode a cult fish on the weekend that i was looking to shape a similar board for myself. 6’2, typical fish width and thickness and reasonable butt crack, nothing unusual about it.
paddled well, duckdived ok too for the shape/thickness. it has a thruster fin set up but since i want to shape a twinny i took out the back fin. i noticed that it was hard work on turns. i figure twinnys are loose but the extent i felt was not what i expected.
is this typical of twin fins? or could it be that the butt crack and rear fin has pushed the front 2 fins up too far and therefore no good as a twin fin?
is this a case of trying to mash together 2 different designs and not really succeeding at either?
well thats how i described it. although i assume you are meaning that its only a fish if it has 2 fins? i thought it was more to do with shape, as there are tri finned performance fish, quad fish and burtons bat fish etc…
anyway, its all relevant to my question, if i shape this board as it stands, and leave the front fins where they are, will it perform better with a small trailer? or maybe even a quad, or should i move the fins back?
I’d have to say if you want a twinnie, build a twinnie. Typically, I’ve found that you can’t just take a thruster trailing fin out of a board and surf it as is and get any kind of performance out of it. You need to at least put in bigger fins to get any idea of what it’s supposed to feel like. Chances are, the “hard to turn” feeling had nothing to do with the fin location… more like lack of grab and drive from having no trailer and too small rail fins.
Anyway… if you want a true “twin fin” shortboard, and not a fish, look at the MR twinnies. They’re not fish, and they’re meant to be surfed more like a single fin than a fish.
I’ve found that most “twin fin” shapes that are not fish work better with a small trailer, often refered to as a “stabilizer” on those kinds of boards.
I f you want to ride it as a twinnie pull those fins back to about 8" or so and put in a set of plugs for a stabiliser. I buit a 6’2 x 20 1/2 x 2 5/8 last year for a guy who tips the scales at about 90kg + with this setup and he is frothing on it. Put it the MR fins. he still gets projection out of turns and good enough hold from the trailer. He is an extremely good surfer as well. I think this board design even lends itself well to the Mckee quad setup as well.
cool thanks for that NJ surfer and Daren, i am 90+ kgs (lets leave it at that) and ride shortboards. i was looking to shape a board more suited to the summer mush we are about to head into. am i on the right track? In your opinions, am i better with the MR shape twin or keep the more traditional shape and make as a quad maybe?
whats the best bottom shape for the 2 different boards?
Speaking for myself, I’d take the Cult shape over the MR. The wider template should make it easier to plane over and thru flat sections. I think it would be neat if you could put enough fin plugs to accomodate a thruster, twin or quad fin configuration. On a 6’4" three finned fish, I’ve placed the fins 12" up from the tips of the swallows and the middle trailer fin (an FCS GX) so the back tip of the fin is in line with the butt crack. For keel fins, placing the fins in line with the butt crack give or take an inch or two seems to be the norm. Twins usually fall somewhere between 8" and 10" up from the tail.
I’m pretty much old school prefering the basic flat to vee bottom on most all the boards I shape. The single to double concave seems to be the most popular bottom contour out now, due to its speed and lift. If you’re adept at shaping a bottom like this it might be to your advantage for the type of waves you plan on riding with it.
As a sidenote, I did have the opportunity to ride a Lost MR '80 retro twin just recently, and have this to say about it. There were a few things I liked and some I did’nt. I thought it being 6’4"x20 1/2"x2 3/4", it would paddle and catch waves easier (I only weigh 138 lbs.), probably a rocker I’m not used to riding. The small sweet spot was a bit restrictive. If you stayed on the tail, you could do whatever you wanted with the board, but if I scooted up a little to get through a flat section, I could feel the board bog a bit (probably the rocker again). On the positive side, even in the small, knee to almost shoulder high south shore waves, I could get it quite vertical and was surprised at how quick it would come around on cutbacks. These are a one time use opinion so it may be a bit too premature an impression to share, but maybe using it a bit more may change my whole outlook on this board.
First… all input is valuable, even “one time” use anecdotes.
I think you could either go for a traditional, twin keeled fish, or a more “modern fish” with a quad setup, and be equally happy with both in summer junk. You might squeeze a little more performance out of a slightly wider, flatter, thicker “shortboard” type template, with a wider tail and shallow single to double concave and quad setup, if that’s what you’re looking for. A good ol’ fish with twin keels will let you catch just about anything, but will limit you in terms of snappy, tight turns. Typically, these boards have pretty flat rockers (especially in the tail), down rails, flat to vee bottoms, and are a bit shorter and thicker than your “modern fish.”
I’d save the twin fin for another project. They work better in better waves than either of the two types of fishes. I’ve owned the MR twin, a quad version of the MR twin, a traditional keel-finned fish, a thruster “modern fish,” a quad version of a “modern fish,” and a twin fin with small stabilizer. By far, the best all-arounder is the modern fish with the quad setup. Works in thigh high slop up to thick, overhead tubes (not ideal, but it works).
Pre-thruster there was the single fin, which was primarily surfed off the tail and the center fin. If you really wanted to hook a turn you weighted your back foot’s heal heavily disengaging most of your rail and pivoted off a small portion of your rail furthest back and the single fin in the center. Single fins were all about control and the style was to flow with an occasional big redirection thrown in.
Or you could surf a twin fin, like MR or Buttons. Their boards surfed more weight forward and engaged more of the rail. Their lines were shorter and rounder. They were less into flowing and more into direction changes. Having fins out on the rail meant they could be shorter, because when you get up on rail you’re not leveraging the bottom half of you fin out of the water. That meant tails could be wider and templates could be more curvy. But, what you gained in manueverability you lost in control.
The thruster was an evolution of finding a middle ground between these two extremes. Quads, Bonzers, Twinzers & Thrashers are all compromises towards the middle of a spectrum with manueverability Twin fins at one extreme and control single fins with long drawn out pin tails at the other. Where you want your board to fall in that spectrum is entirely up to personal preference. But, there are factors that work well together and some that don’t.
If all we are talking about is the fin setup on a Modern Fish, then the more manueverable you want it to ride the bigger the side fins and the smaller the trailer. The side fins should be right where you tail outline is at it’s most curvey and that’s right wher you want to place your back foot. The more control you want the smaller the sides and the bigger the trailer.
For the summer stuff I’d go with something more like the cult board. I really think the bigger guys need that extra nose area in the tiny weak summer waves.
I drew one up yesterday 6’1 x20 1/4 x 13 N x 14 1/2 tail this will be a quad with centre plugs.
I have been throwing a single concave From under the chest/Front foot, all the way out through the tail on most smaller wave boards lately.
hey Daren, thats pretty close to what i settled on last night too.
i know there is alot of info in the archives regarding quad fin set ups which i am slowly wading through but what do you favour if you dont mind me asking? i also was thinking quad with the centre rear fin so i can play a bit and get some useful info from my own fin combinations. i have a square tail quad that i like, so figured would stay in that groove. is the centre rear fin inline with the back set of quad fins? do you have you fins parallel? more cant than normal and the same for both sets?
I run my front fins at about 11", trailing edge 1- 1 1/8" in from rail toed in about 1/4" canted out at 5 degrees,and the rear fins at half the distance of the front fins, trailing edge 2" in from rail toe in about 1/8" or less and canted out to about 2 degrees.
My very back or thruster fin I have at about 3 1/4" up from the tail.
This is the setup I’ll be using on the board I mentioned before.
I put the FCS SF4 fins in a 6’4 board of around about the same numbers and the guy loves it. wont even try another set of fins.
No worries about the questions, I’ve learnt so much from the people on this site that whatever I can do to help someone else out, however minor , I’ll try and answer the best I can.
Good luck with it and post some pics when you’re done.
thanks Daren, i am trying to get underway this week- with work and all it takes a while to get a board done. but yeah i may take some photos of this one and post if it comes out ok.
i took a look at your website too, your boards look fantastic…
sweet, now thats inspired me all over again, unfortunately work has got in the way again (hence why i am here at 3 in the morning… gotta love the 15 hour days) but as soon as i can get my sorted i really want to have a crack at a board like that. looks like a perfect summer board. i would like to use the measurements you have quoted if thats ok.
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