Good looking board Monty.
Others have also mentioned the McKee setup is too far back for their liking.
I’m going to stick with the Speeddialer layout I have and see how it goes.
I’m pleased with how the placement looks on the board.
Yeah Nuclear, good point. I did mark to the back of the base, not the line where the back would be without the cutaway. Makes total sense. Thanks for the observation.
Progress & photos:
Setting fins in place using 2 minute glue, an angle jig and masking tape.
Glassing fin bases.
Sanding fin bases.
Pinline on deck.
During sanding. (Light was very bright outside, board is a lot darker than it appears in this photo.)
Need a couple more hours sanding before finish coat… then cure…
sine
~
(so the image uploader now puts them inline automatically, in reverse order. try to remember for next time.)
Are the Mckee specs to the back trailing edge of the fin,the center,or the front of the fin?
Back edge.
Groovy.
I’m excited to hear how it goes for you.
I see you’re in South Africa , cool ! I’ve often wondered why more SA people don’t get involved here.
just finished this, came out ten times better than i expected, but still, glassing ridiculous tails is neither fun nor easy
Hey Nuclear, I’m excited too.
Really pleased with the lam and how easy and good the fins turned out. Just got to be patient, I want to finish and pollish and let it cure properly. I can see this board going really well… want it to look the part.
I’m in Cape Town. I know one other backyard shaper who shapes and surfs his own boards. Actually met him on the beach when I took my first homemade for its maiden surf. I noticed he had a homemade fish glider (his first as well) on the roof of his car and we got to talking. Other than that I haven’t seen any homemades in the lineups, but I have seen a few people at my suppliers enquiring about surfboard lamination.
I don’t think ‘internet communities’ are that big in South Africa. I come from an IT and design/development background so I know the advantages of being able to share and aquire knowledge from hundreds of experienced people without having to leave my desk. I also think most younger people here aren’t that into ‘making things’. I work in the trades now, cabinetmaking, which is where my interested in shaping boards started.
I do about 80 % quads of late, maybe check out my stuff at www.moresurfboards.com , glad to discuss fins if you wanna e-mail via web-site…
that is one serious bat-tail on the blue number…I do a few of them too but that is a big arc, did you use a paint tin for a template ???
Howdy all,
just to say that my distances for the back fins from the tail block, are meant to combine with the width between the back fins.
Having the back fins large, fairly straight and out on the rail, will not compliment my positioning.
My original quads 1982 era, had slightly larger rear fins than the forward fins. The toe-in angle permitted them to work well though the whole cluster was eventually moved rearward as the board was subject to oversteer.
My direction in development with the quads, was towards boards for power waves and power surfing. The fish idea was not in the focus as this is where the hard core ‘thruster’ devotees wanted it to be catagorized, ridiculed and forgotten.
Obviously, moving the cluster forward and squeezing it together will loosen up a quad. It depends on what type of the zillion quad options you want and for where you want to ride one.
Noticing the fotos in the forum I see that my formula, which emphasised the width between the back fins spacing, was not adhered to. This is great as experimenting is fun and sometimes the pros outway the cons, if you're prepared to adapt to the cons that is.
Having my rear fins further away from the rail, with a distance between the rear fins proportional to the tail width at 12" up, the fins have a certain amount of combined hold that combines with other factors.
If you use only my distances from the tail and set the fins on the rail then you will find the board too stiff, over finned and a probable ‘rail-grabber’ plus a load of other negatives.
This is old school and I have been through that stage with
unfortunate consequences but some positive ones also. More toe-in may
alleviate some of the problems, fin size reduction may also compensate,
though in the end, my complete positioning was based on using all fins
of the same size giving the board a balanced, neutral feel that is not
skittish, and that handles a vast range of wave sizes. Different foils,
flexes etc came after that…
My aim in the past, was to eliminate the ‘stuck one tack’ feel with the body gyration to come down off the lip or the delayed recentering after each turn feel… . though during the early days I got used to all that. For the ‘Thruster purists’ though, it was not permissable, so I had to find the ‘Thruster-like’ feel but with the Quad benefits of hold, speed and fluidity. The big Eureka was the relationship of tail width and the distance between the back fins.
Now, slight changes in fin proportion front and rear, flex etc are subtle ways of tweaking each board. Big changes give extreme reactions.
A fin system with forward and back movement and more, is also a benefit, though if all the formula info supplied is analized, with slight additions or subtractions to my formulas, great ‘glass on finned boards can be produced’. Some will have their own formulas for different board lengths if they’ve had time enough to work on them. No doubt many may find positions more favourable than mine. If you read my suggestions in the web-site I recommend the forward movements of clusters according to the need and the board. I could go on forever with different types of formulas for different needs… it’s endless.
I have recently refined the fin position formulas to cater to all board lengths, tail widths and fin distances from the tail.
Main adjustment is a slight increase to the distance between the back fins and a big graph to cover the grey areas.
For those interested in the latest February 2009 updates, go to http://www.mckeesurf.com/brucemckee/multisystem.htm
The width between the back fins is a major factor that brings all the benefits of quad fins together. It’s the proportion to the tail width that’s key. Combine it to a bunch of other key factors, toe-in and fin angle, shape etc… and you should have a great board… depends on your taste…
Look out for the new FCS M4 McKeeQuattro fins, available as inside foil or double foil. Size between M3 and G1000. Designed as a rear fin to mix with whatever but works as a full neutral set for lighter to mid weight riders… great for tow-in boards also.
Cheers. M.
Below is first Quad ‘Quattro’ 1982
A couple of months ago, you helped me with placement on a 7’0 for bigger winter East Coast surf. I call it an East Coast Gun… not a “gun” or even a “semi-gun,” but basically a shortboard for the big days we get around here.
I guess you clued me in to the new formula before you put it out there, because the specs you gave me are pretty much identical to the Feb. 09 update. Yesterday we had some solid surf… the wind was offshore and the bouys hit 9’+ @ 10 sec., so I got a chance to really see how it works for the kind of surf it was intended.
Board: 7’0 x 11.25 x 19.5 x 14 x 2.5; single concave, pushed a bit forward; vee out the back; double wing to mini-swallow.
Fin Placement: 12.25 up for the fronts; 6 1/16 up for the back; back fins 6" apart. Both sets of fins point beyond the nose, but I don’t recall the exact measurments. They’re whatever you suggest on your spec sheet.
Fin System: Probox; fins set in the middle of the boxes for the first test drive.
Fins: Guy Takayama quad set; height: 4.75 and 4; base: 4.5 and 3.875. Fiberglass. Front fins very flexy. Back fins stiffer.
Performance: I typically ride the same size fins, front and back, but Probox Larry said the Takayama fins are specifically designed for bigger surf. So… I found the placement made the board feel remarkably loose and responsive, not tracky at all. The old fin placement had great drive, but you felt like you had to jam the turn harder to get a more thruster-like turn. That could be my fin choice, but that’s my first impression of the new placement specs. With the new numbers, late drops falling into bottom turns maintained control without sacrificing sensitivity. On super steep faces, the fins had excellent hold and were super fast… the kind of speed you feel on a twin keel fish when the waves are maxing out the board. Just incredible down the line speed. I think this has more to do with the toe-in angles, rather than the placement. I’ll most likely move all the fins back in the boxes next session to see if I can get a little more stability coming out of the turns. Getting the board up on a rail was quick and had a very positive feel, but I felt like I was “over steering” coming out of the turn.
A note about the Takayama quad set: I feared that the fins had too much rake for me for bigger waves. But the fin designer says the rake is “an illusion.” Whatever… The truncated tip on all four fins makes it feel like a fin with less rake. But the most noticable feeling was that of smoothness in the turns. Felt like a brand new car with power steering. Really smooth and floaty. I think the flex in the front fins, combined with the stiffness of the back fins, helped smooth out the turns, while maintaining drive.
I’d love to hear some other thoughts/opinions…
Hya NJ_ Surfer,
great to hear that in general that the board is going well...!
Interesting fin mix.
The flexy front fins let the front half of the board drift out and the stiff backs give some direction but are overridden by the bigger fronts… Gives a good swim-fin like boost to a smoothly executed bottom turn.
A good test would be, all fins of medium flex, of a size in between the two that you used. A full set of G-AM size equivalent plus an extra back fin for example… something more upright… M7 size equivalent or what ever suits your weight… Heavyish if I remember rightly…
Your test reminds me of when I used the old flexy, larger, FCS G5 on the front with stiff, smaller, double-foiled G3 on the back… similar feel to how you describe.
I prefered them the other way round at the time though, but the waves had some power and I could stand on the tail. The feel was definitely smooth as you described but a bit insecure… If I had have had a mid-flex of a size and area in between, I would have been happier still… maybe…
I think that back fins being around 5% smaller than fronts is a good combo to compliment my formula positions etc… though…
I’ll have to try some more exotic mixes as you are doing… . maybe my H2 large fronts with those wing tipped 3D backs wasn’t a bad effort… but need to get into the water more…
Looking forward to hearing more of your own experiments though… I’ll add them to the data bank…
Thanks and Cheers. M.
Photo is of the larger but flexier ones on the back… a favourite for many years…
Sorry guys having problems uploading pics to larger size. Help! Mahalo, Larry
Lemme see if I can post some pics…
Wow Larry that’s a crazy looking set of boxes… It’s funny I was thinking about that a little while ago, wondering if people had installed extra boxes like that to allow for totally different quad setups on the same board. Do you think that squeezing the extra set of trailer boxes in there makes it harder to make either setup a 100% functional one? …in other words do you feel that each setup loses something by making room for the other? Just curious… I presume that with the proboxes that would be decreased by the ability to shift the position and cant. Still…
Also, are those just probox inserts flipped upside down and used as plugs on the unused boxes? Nice solution, if so!
And props to the originator of this thread, I’ve been stoked on my new quad and getting used to surfing it… watching this thread is inspiring me to shape my next shortboard as a quad instead of a thruster. Gotta admit I’ve felt a bit intimidated by the extra precision required of placing a quad setup! But they appeal to me in a big way. Think I might try to a shortboard with a tail inspired by the Bing Synchronizer. I’ll be on here asking advice when the day comes for sure.
I’m stoked on this thread!
Having trouble with uploading pics… I’ll try giving you a photobucket link.
Hi BCKyle, The plugs are what we call “Anti Drag Inserts” that float. This allows the surfer to fill the box not in use and add positive weight back into the board with still having a smooth water flow over the bottom of the board. So in the water world there is no extra weight with extra boxes, just more options. The pic below shows Anti Drag Inserts.
Mahalo,Larry
Thanks for the reply Larry! … that’s a good idea, especially these days with more and more boards popping up with extra boxes for setup versatility. I’d considered how to make something makeshift to plug empty boxes, but hadn’t even really considered the value of giving them positive flotation.
Nice.
NJ, Hope I don’t seem like a know - all tool , but there ya go.
