I’m planning on working with my local board repair shop to insert a center 5th fin into my existing Stretch Quad board. Is this a good idea? How will it affect performance? Should the 5th center fin be placed exactly horizontal to the current back 2 fins? Am I crazy to do this to my rather expensive board that I saved months and months for?
If I was you and I realy wanted to do this, I would add a 10.5 centerbox 3" up from the tail
gives you the option of 3 ,4, or 5 fin setup
what kind of tail is on the board?
if you use a small fin box I would put in conjunction with utilizing the front finboxs
Just do it. Whats theworst that can happen ??? you dont like it as athruster so you ride it as a quad…I sometimes do my quads with a extra fin but 99% of customers continue to ride them as a quad…If you wanna try it, just do it…or make yourself a board and do all the work yourself and try out the fin placements you want and maybe some other stuff…heaps of fun…if you wanna check out some pics of my quads with centre tail fin for placement, go to www.moresurfboards.com
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I’m planning on working with my local board repair shop to insert a center 5th fin into my existing Stretch Quad board. Is this a good idea? How will it affect performance? Should the 5th center fin be placed exactly horizontal to the current back 2 fins? Am I crazy to do this to my rather expensive board that I saved months and months for?
Hi dqp, Here’s a board that Eric Arakawa did for a guy. Eric placed the ProBoxes on this board in his Tri Fin positions first then added the rear two to make a Quad. Hope this helps. Mahalo,Larry
I’d measure and check out the placement of your front two fins first
that board could go great or it could be too stiff.
Front fins on quads can be canted and toed in differently to a thruster
i don’t think it will ride very well, especially in steeper/hollower stuff. part of what makes stretch’s quads ride so well is the extra tail width, which i think will make a thruster ride kind of funky and not hold as well. and, like the other guy said, the front fins are towed in less, so it’ll go fast down the line but not turn exactly like a thruster.
maybe compare the tail width to your stock thruster and see?
Hey Tommy - you’re quick to absorb and process surfboard design. Good observation about the width in the tail of quads compared to thrusters - an absolutely essential consideration when configuring a fin set up.
dqp - No. You’re not crazy to do this to your rather “expensive” Stretch quad. (By the way, ALL surfboards are a bargain - no matter the cost. No matter how big a chunk they take out of your budget or how long it takes to save up for the purchase. Skilled surfboard craftsman are some of the truly underpaid craftsman in any trade. But that’s a topic for another thread.) You may find your “quad” will feel a little bit sketchy (lack of control rolling onto rail - particularly in fat or mushy places in a wave) when surfed as a “thruster.” The thruster fin configuration can be hard to control on the extremely wide tail dimensions of most quads. Consider the total surface area of two fins on or near each rail of a quad compared to the surface area of one fin on each rail of a thruster. But don’t let that discourage you from going ahead with your experiment(s). Kensurf’s idea is a good option . You may want to consider an 8" Fins Unlimited box instead to minimize the affect of the weight and open cavity in the bottom of the board on the board’s performance. You could also use an O’Fishl box as they are designed to install with cloth over the box. (Keep in mind the availability of rear thruster fins for the FU or O’Fishl box.) It will be essential to glass over whatever box you install - assuming the Stretch quad is an EPS / Epoxy board. Or you could install the same fin system’s rear box in a thruster’s rear or trailing fin position. Whatever you decide it is in the true spirit of Swaylocks.
Quads are pretty cool design. They are very functional - arguably the best incarnation of the twin, twinzer, four fin, quad concept. For many surfers though, the lack of a “center” fin can be a problem. Depending on your “technique” and “skill” quads perform very well and/or can really make it difficult to transition from maneuvers in the top of the wave to the next bottom or down the line turn. Without a center fin quads tend to be entirely surfer dependent on returning or centering your board under your feet and center of gravity - extremely important for setting up your next turn. The center fin on a thruster allows your board to center itself under your feet and center of gravity naturally and independent of your technique or skill.
Hello all. Much thanks to all that responded. I’ve decided to not mess with a good thing and look for some used 6’2 to 6’3 thrusters instead. Again thanks for the replies.