Quad fins with stabilizer fin (some might say knubster)

[Slowman]

This last weekend in Sydney we got a nice little pulse of swell. Which gave me a chance to try my new dominator in some reasonable waves. Friday was about 2-3' and Saturday afternoon was about 5' and Sunday morning before the NE came up we had clean 6' (somewhere south of Sydney) and maybe slightly bigger on the bombs.

Saturday was a really nice surprise as it was a very light southerly. Southerlies are badness usually but this was just puffing every now and then and the conditions were glassy and only half a dozen of us on the whole beach! Uncrowded waves on a Saturday afternoon - a real delight. The crew had persevered with the morning's 2-3' and gone home and the NE swell built all afternoon. If you're not getting this, it was bloody good! For me especially, as I decided to make a little stabilizer fin for the 5th fin slot on my dominator - if Kelly does it, it must be good, right? So I gave it a try, all those concerns about the dom not having enough drive and pivot and surfing kind of flat were put to rest. It just went insane, on rail turns, vertical in the pocket and more speed it seemed than with just the quads.

Here was my first attempt, the "slug", a GX cut about 3/4" trailing back down to 1/2"...
28
It really made the board go the way I wanted it to. I always felt that quads need a little bit of something down the centre to give them something to pivot off, a double concave gives you a ridge which does the trick and I think the centre vertex (pointy bit) of a bat tail helps too. The dominator being a single concave needed a bit of help and this seemed to work well.

The next day, Sunday, we had some clean 6' waves early in the morning and I'd decided to go for a more refined looking stabilizer fin more like the knubster shape though only half its height at 1". This one was an MR TX trailer fin which I cut down and foiled. Perhaps just for the aesthetics. Here it is...
29
It is hard to say which one works better but I'm thinking the first one despite its cruder looks, either way they both work very well. I have a feeling the first one is a tad looser because it is a little bit lower and the highest point is further forward. One thing's for sure - I'll be keeping the Dominator!

[buzzy]

Interesting observations.

I surfed my Dom on saturday in Sydney but there's no way I would surf my Dom 6'4" with me at 90kg on Sunday. It would've been way too floaty. So I surfed the Alternator on Sunday. I say interesting because of discussions in the old forum around board length and volume.

[buzzy]

...sorry, interrupted by a delicious pasta by my beautiful wife mid post...

I meant to add that the different preferences in the same conditions reflect on intended use. I don't mean to and I'm sure I won't derail a thread about 5 fins but this kind of difference in intended purpose is (I reckon) important background for people agonising over board size.

Just on the 5th fin, was there a noticeable increase in drag? Did it surf more like a quad or thruster? Something else?

[Chris]

that looks cool. good feedback. I'll have to give it a go....

Buzzy its good to have differing opinions. I have been learning a lot about length, shape and volume since I moved to CA and can surf so frequently and one of the things I have learned in the last few weeks has to do with what you are talking about. Volume definitely is valuable but its paramount to remember length. I did find my optimum volume but did so by sacrificing a bit to much length. I dropped to a 510 Michel bourez as my shortboard.

Then i did a bit of video and watched myself and realized on my first wave that I was riding too short of a board and was overloading my rail around my front foot too much and bogging. After not riding my Alternator for a couple months I got back on it yesterday and realized that the extra 2-4 over my other boards was exactly what I was missing. While I like having limited length, having the right amount of rail enables you to maintain speed through your turns so much better. A bit of a ramble, but a REALLY big piece for me (obviously this could be different for other folks).

cheers

[prjwebb]

That little stabiliser looks cool. I might try and make up something similar.

As for rail length Chris, interesting for sure. I haven't ridden a board over 5'8" much at all in the last year. I probably should, because I know exactly what you mean about that length in the rail, but stubby little boards are a lot of fun.
I guess with the MB it's a little different because it sounds like it's a proper refined shortboard rather than a chunky stubby, so you're surfing it in proper lined up waves where that rail length really earns it's keep. I think the MB is really going to come into it's own for guys like MB and Taj who can ride that refined a board in smaller conditions where you don't want the longer rail, or guys who are bit more weighty but shorter who can get the volume of, say a 6'4", in a 6'0" so they don't have to ride a board that's 8" longer than their height. They are then reducing a massive rail length that would be holding them back a little otherwise.

[Chris]

yeah there care certainly pluses and minuses both ways. I got stuck in the rut of reducing everything BUT volume. Don't get me wrong the michel is a sick board, i just think i like shorter railed board in steeper hollower surf where my maneuvers are more vertical. I like a little more rail obviously when my maneuvers are more wrapped.

Keep in mind though, Taj is 509ish 160ish and he rides a 511. I am 600ish and 175ish and went from a FFE 602 to a FMB 510. That is a big change and a lot of lost rail. The Michel works great, you just need a bit of punch because with a minimized rail, you shed a lot of speed in your carves because you tend to bury more board. Again not a bad thing just a fact.

Cheers

[Slowman]

...

Just on the 5th fin, was there a noticeable increase in drag? Did it surf more like a quad or thruster? Something else?
No drag, in fact more speed. Because of that something else - a thruster on steroids/speed?

On the speed thing, it makes me wonder, as Kelly even said they add more speed, if the unused fin slots are actually creating drag. In the past I've thought about just putting tabs in there to fill them in and create a flush surface to see if there is any noticeable difference.

[prjwebb]

yeah there care certainly pluses and minuses both ways. I got stuck in the rut of reducing everything BUT volume. Don't get me wrong the michel is a sick board, i just think i like shorter railed board in steeper hollower surf where my maneuvers are more vertical. I like a little more rail obviously when my maneuvers are more wrapped.

Keep in mind though, Taj is 509ish 160ish and he rides a 511. I am 600ish and 175ish and went from a FFE 602 to a FMB 510. That is a big change and a lot of lost rail. The Michel works great, you just need a bit of punch because with a minimized rail, you shed a lot of speed in your carves because you tend to bury more board. Again not a bad thing just a fact.

Cheers

I know what you mean about reducing everything down. I think in a way that's what happened with Slater in that off year he had, when he started riding 5'5"s or whatever. Lots of fun, but if you start doing it in the wrong conditions it's not going to allow you to draw the "best" line on a wave. Hopefully 6'0" is going to be my magic number, but I'll probably still end up on a 5'8" 80% of the time.

[Slowman]

Just went for a surf in 3' foot onshore slop leftovers after the southerly ripped into it all day yesterday. I swapped the stabilizers around but it was really more of a matter of chance getting a good wave, I definitely got more good waves on the "knubster" than the "slug" but that was purely because I spent more time in the water using it, say 50 minutes vs 20 so the odds were better. Test results are still inconclusive.

[core personal training]

i agree with the rail length thing...jumped off 510 onto my 604alt(too big for me now) the other day and as chris noticed, the front foot action comes back...BUT...you no longer fit as freely in the wave as the shortened boards...this is where my love of heavy rockers comes in to play...i was one of the few who really loved the "banana" era...i rode em at 6'6(no front foot woes there chris) and could fit in any tight spots...

[core personal training]

here's the original use for that knubster thing...aka cannard5960

[justo]

Rusty hipster?

[core personal training]

yup...one mick buttons...6'2...one of the rare few I gel with that are not nev's shapes...you have one too dont you?...

[Chris]

Yeah core that is definitely the solution, or at least a good option. I think what i am figuring out is that I may step up in length a bit with more rockered boards.

Going to spend a bit of time again on the 602 Taj and also ride the 600 Michel for comparison with my 510. its weird, 1 day on a longer board and the links between my maneuvers were tighter and faster and I could tell I had a better balance between burying and bogging to the point that it slowed me down....

[core personal training]

yeah chris..gotta find that sweet spot between rail length and freedom...rocker does skew the formula tho...eg..the 604 taj rode like a 602 or less and fitted in tight spots compared to a standard 602 shooter..but still has full drive rail line....604 alt feels like my old 6'6s at least..this is generalised tho and not in all situations...usual caveats apply......michels model will be along the lines of what our fearless leader shaped me in the past...full rocker and some chunk...might give it a run i think...

[Chris]

yeah its a good one. Chuy and I are the same weight and he is claiming the 600 Michel. Yeah you get in a rut going short, but it really comes down to preference in the end. The volumes of all my small boards are spot on, i just think the length isn't there that I want. gotta keep experimenting.

[beatlloydy]

talk about hijacking the topic..this thread was on the knubster..and the pros/cons ...not one volumes of boards etc...tho all good info but perhaps best in a separate topic... I have ordered a single fin and gonna try the same...cut down to the specs of the Kelly Slater model...As my Dominator is Futures was a little harder to find any crappy old ones at home...plenty of FCS.

Will be interesting

[buzzy]

Threads are like conversations...actually, they ARE conversations! You can't control where they go. As you say though all good and all interesting.

I just saw FCS have released a 5th fin they are calling a Kelly fin. Maybe, maybe not....who knows. It'll be interesting to hear how it goes as more people use it. I haven't even tried out my controllers yet, and just having had a...something...cut out and all stitched up I'm out of the water for at least another week. Grrrr. I kind if get the feeling that there's a general swing back to a bit more length (see comments above and also comments from Kelly at pipe about being under boarded).

[Chris]

agree buzzy...free flowing. speedy recovery...

[Slowman]

Had quite bumpy surf this morning and the "slug" gets a little unsociable when you bounce around during a turn, you can definitely feel it let go.
http://www.firewiresurfboards.com/f/attachment.php?attachmentid=28&d=1323669602&thumb=1
I expect that is because of the low almost straight profile which gives it a real on/off effect. I will be trying some more refinements to make the change a little more gradual rather than such a sudden loss of hold. If the bounce is big enough it will be out of the water anyway but perhaps with more curve it won't be so sudden and more of a graduated change. It certainly feels as though the more knubster like one suffers much less from this effect when in the lumpy stuff.

[Fritzkat]

Strange that Futures or FCS hasnt sent out a new Stubby 5th fin model yet. However, I now use thin packing tape now to cover the unused fin slots and I notice less drag at high speed driving.

[Slowman]

Strange that Futures or FCS hasnt sent out a new Stubby 5th fin model yet. However, I now use thin packing tape now to cover the unused fin slots and I notice less drag at high speed driving.
You mean like this one (http://www.surffcs.com/au/products/fins/Quads/vsknubster.aspx). I don't know how long it has been out but it is on the FCS website for Oz. I know that Kelly was using it in NY...so perhaps since then.
http://www.surffcs.com/imageprocessor.ashx?fid=f1b68ee4-c7de-4cbb-9c63-b2a054fd4420&mHeight=320&mWidth=320

[Slowman]

... However, I now use thin packing tape now to cover the unused fin slots and I notice less drag at high speed driving.
Now that is interesting. I suspected these open slots were creating some drag and it would be worse in a thruster configuration with 4 plugs vacant.

[Chris]

yeah having the tabs open is less than perfect, but I personally have never finished a session and felt that my empty inboxes were letting me down.

one way to make cheap plug fillers is to take an old set of fins, cut the tabs off and drill 1/16" holes about 1/8" deep into the surface of the tab exposed while the tab is in the box. Then you can use a 1/8" drywall screw to pop the tab out when you need to use the box. Works for both FCS and Futures.

I don't do that myself, but its an easy way and probably more reliable than tape? better for the environment too as its unlikely they will fall out.

[Slowman]

yeah having the tabs open is less than perfect, but I personally have never finished a session and felt that my empty inboxes were letting me down. ...
Nor I but without having ever tried it and not knowing the difference you can't recognise whether there is any detriment.

Some polyurethane tape cut to circles would fit nicely over FCS plugs and seal out water too. We've been using this stuff to protect our nice carbon fibre frames in mountain biking for years now. You wouldn't want the same grade as used for frame protection as it has quite a strong adhesive which would make removal interesting - it could possibly tear off the finish coat. This stuff is used to protect helicopter blades too (aka helicopter tape). So reliability wouldn't be an issue though re-usability might be, you could perhaps re-use it a few times whereas the fin tabs would be re-usable indefinitely.

[Mana]

perhaps some silicone filling out of a tube or self-adhesive sealing tape cut to measure would do the trick as well? and removal wouldn't cause harm to your board. or just use stickers.

[Fritzkat]

The super thin packing tape works great in the Futures rear quad fin holes (FUTURES have a much larger slot to cause turbulence drag.), after 20 sessions nothing has fallen off. Good for quicky ding covers as well. I would like to get a futures stubby fin when I ride it as a Quad. I just saw that FCS stubby posted by slowman. I may just cut an old composite fin down and try that for size.

[Alberto]

since the NY Quik Pro i had been itching to try a knubster/guitar pick on my 5'8'' dominator and thanks to slowman i finally got around to foil an old G5 fin i had laying around. I more or less copied slowman's design to use it with my R-2 quad set:

http://i156.photobucket.com/albums/t28/bertas_photo/Surf/IMGP0456-1.jpg

Well, i took the board out today (in 3' to 4' long walled rights with a light offshore) and the board felt incredible. Very fast and drivey.

You get the feeling the knubster doesn't create any extra drag and just manages to give a bit more hold to the quad set. I usually prefer to ride the dominator as a thruster in any kind of surf over 3', but from now on i will now try to use this setup more, especially in waves with long sections.

I think the dominator with it's large tail is particularly suited to this kind of setup.

[Chris]

Alright....

So folks. I am actually taking this thread really seriously. I want to know from the people who have tried riding the knobby style fin the following:

Board model
Board length
your weight
surrounding fins


pretty interesting stuff....I want to archive it!!

Thanks all for the progressive approach!

[Slowman]

Model: FST 6'0 Dominator
Length: 6'0"
Weight: ~92kg
Fins: FCS R-2

So far both test cases, mine and Alberto's are using Rusty R2 quad sets, I am thinking of testing this set up with K2.1 quads as well. I also have some other ideas for the shape of the stabiliser that I want to try too.

[Alberto]

my case:

Board model: FST Dominator
Board length: 5'8''
weight: 78kg
surrounding fins: FCS R-2 Quad

[kdropin]

5'11
170
5'8 dom
k2.1s, mayhem rears, knub

went really really well. had it in waist to head groundswell.. so fast and fun

[Chris]

keep it coming, good stuff....

Going to kind of put together a little list. Cheers

[Slowman]

5'11
170
5'8 dom
k2.1s, mayhem rears, knub

went really really well. had it in waist to head groundswell.. so fast and fun
Mayhem (aka GMB) rears are Q1000s, which are what the K2.1 quad set uses too, so apart from the colour mismatch it's a standard K2.1 quad set.

Chris, I hope you are going to do some of your own research first hand too! I am wondering whether the Spitfire would see as much benefit when ridden as quad.

[Slowman]

coffeeshopmillionaire (http://2yd.net/1jk)
look out the spambots are coming, time to implement anti spambot registration measures before the place is overrun

[prjwebb]

look out the spambots are coming, time to implement anti spambot registration measures before the place is overrun

Good call. Post it in the suggestions thread!

[Justin]

look out the spambots are coming, time to implement anti spambot registration measures before the place is overrun

i just implemented some anti-spam stuff, literally 2 nights ago, i noticed a sudden drop off and then damn there was a lot this morning. i think the filter i put in place still needs some "training" ... meaning when i delete spam and ban the user, the system learns, remembers and enforces stricter rules with each new submission. thanks for your patience with this.

[aurfalien]

Yo,

6'1"@150

5'11" El Feugo
K2.1 Quad
Nubster

[Chris]

Yeah 40 posts from this guy in 8 hours


ayomalkdu

[Chris]

thanks for the info Aurf

[kdropin]

Mayhem (aka GMB) rears are Q1000s, which are what the K2.1 quad set uses too, so apart from the colour mismatch it's a standard K2.1 quad set.

Chris, I hope you are going to do some of your own research first hand too! I am wondering whether the Spitfire would see as much benefit when ridden as quad.

no its not the foil is different.. the k2.1's are flat foiled the mayhem are 80/20

[Slowman]

no its not the foil is different.. the k2.1's are flat foiled the mayhem are 80/20
Yes indeed, my "fail"! I just checked mine and they are 80/20 and so are the Q1000s that came with the flat foiled GAM front fins too.

Just out of curiosity kdropin, did you try the original flat foiled K2.1 Q1000s? Did it make much difference?

[kdropin]

Yes indeed, my "fail"! I just checked mine and they are 80/20 and so are the Q1000s that came with the flat foiled GAM front fins too.

Just out of curiosity kdropin, did you try the original flat foiled K2.1 Q1000s? Did it make much difference?

no i didn't i have the thruster k2.1s and bought the mayhem quad set for my spud and used the rears with my k fronts on my dom with the lil nubster.. i tried getting my hands on the k rears but couldn't find anyone just selling the rears and didn't want to buy the whole quad set..

[Slowman]

my range of stabilizers that I'm experimenting with now...
187
The first is the "slug" after some refinement, yet to be tested. The second and third currently being tested. I'll update with some comparative results later - once I work it out!

[iggy]

Some R&D there slow man, keep us posted

[prjwebb]

I have the flat k2.1 quad rears. Kelly actually uses different ones to his sig set and I believe that is because he prefers the 80/20 foil.
I can't remember the difference but I did read somewhere on surfermag forum what the effect the foil difference had.

[kdropin]

80/20 helps get board on rail easier

[Slowman]

187
OK I've done a lot more testing and the last one seems to be the most effective, for what I want. The closer the trailing edge is to perpendicular (steeper angle) the more pivotal and direct feel it gives to the board. They all help with speed and drive but I reasoned that if I moved the highest point further forward it would make the board looser but still pivot in the same way. This didn't really happen, what happened was the slacker the angle of the trailing edge the more vague and less pivotal and direct the board felt. The only reason the "slug" worked so well originally was that it had a steep trailing edge, when it looked closer to just a sawn off GX. Once I refined the slug to eliminate the stark on/off feel in bouncy chop, it lost its direct and pivotal feel, pretty much a failure for my purposes - though it may have application elsewhere.

I think the MR TX trailer is an ideal fin to start with to make this kind of fin as it is narrower which I feel also helps with speed and unwanted drag and makes it easier to shape and foil. The thicker fins I tried like the GX and a G-YU (though these were slug versions) seemed to add some drag and cavitation though I'm not really sure, since they just weren't delivering what I wanted I stopped experimenting with them. In fact the G-YU was a much bigger slug (45mm deep) but I've since refoiled it to look more like last one above although its trailing edge doesn't finish as far back and since its height (depth) was greatly reduced it's more or less on the scrap heap. Same for the 2nd one above it has more pivot but not as much as the last and was also a little vague.

So in summary my findings are that if you want more direction and pivot you want a slack angled leading edge curve with the highest point towards the back with a steep trailing edge. The trailing edge finishes about 1/2" behind the last FCS plug (I don't know how that relates to a futures fin box) and the highest point (or depth) is just over 1" with a base of about 3 1/2" (90mm see http://www.finshop.com.au/Products?Product_ID=67&cmd=Display) just like the last one above.

[Fritzkat]

SLOWMAN< shoot the finished template jpeg here..

[Slowman]

SLOWMAN< shoot the finished template jpeg here..
Fritz, it's pictured a couple of posts above (also in the attachment 187 in the roundup post above), it is the last fin of the the 3. If you want a bigger picture of it, I'll put one up later, let me know.

[Fritzkat]

How Big are your back fins, I am not familiar with FCS templates anymore as I use Futures.

[prjwebb]

Sorry if I look like I'm repping CI lately but this is too good a deal to pass up
http://channelislands-store.mwrc.net/en/product.php?product_id=47461
AM Quad Set plus Knubster for $26. Get 'em while they're hot!

[Chris]

ha no worries PRJ....

[prjwebb]

Looks like they've vanished now, maybe it was a mistake of the offer was limited.

[Chris]

actually i did it. infiltrated.

[Slowman]

How Big are your back fins, I am not familiar with FCS templates anymore as I use Futures.
Fritz, I'm not sure what you mean, if you mean the R2 quad set that I'm using a stabiliser with, the back fins are QRs, all the details on both front and back fins, such as area, rake, base, height and so on are on the FCS website.

If you mean the little stabiliser I chose as best for my purpose, and there is only 1 (ie. it is the 5th fin), it has a base of 90mm and height of 35mm
213

[Matt_s]

Sorry if I look like I'm repping CI lately but this is too good a deal to pass up
http://channelislands-store.mwrc.net/en/product.php?product_id=47461
AM Quad Set plus Knubster for $26. Get 'em while they're hot!


PRJ do you recon those fins would be any good on an el fuego? dont know much about the AM fins, was looking for a k2.1 set but that could be a possibility too?

cheers

[prjwebb]

for $26 I'd say there's no harm in trying!

[Matt_s]

too true, only prob is they only ship to the states, I have a freind in NY who would probably take reciept and post em on to me.

The nubster isnt out in the UK yet is it?

[prjwebb]

Don't think so. I just had some fins shipped from the states. In a flat rate USPS package it was $13.95 or something for the shipping. I got the guy to mark the item as a gift and stated that there were used fins inside with a value of $10 and didn't have to pay any import fees etc.

[Chris]

finally a desirable surf item that is wallet friendly....

[hwork50]

So I went down to my local surf shop to pick up the nubster and I picked up a fin called the 5th finner. They did not have the nubster and was wondering what you guys thought about it before I return it and buy it through channel islands. The fin has a 4" base and is 2" in height.


https://plus.google.com/u/0/photos/110891914117254914345/albums/5697346275582005969/5697346274567423938

[Danga]

I just ordered the knubster on ebay ($25 including postage) to try on my 6' Dom (goes good without it but I'll give it a go) then was reading the old forum ( hours of good reading there) when I read about the deviant fin for the thruster. Do these fins go any good? Where do you get them from and how much do they cost? I might get one and give it a go. What fins would go with it? I have G5's at the moment on my board. I also have M3s and FG-3s available from other boards. Would any of these go OK with the deviant fin?

Cheers.

[Wandi]

Alright....

So folks. I am actually taking this thread really seriously. I want to know from the people who have tried riding the knobby style fin the following:

Board model
Board length
your weight
surrounding fins


pretty interesting stuff....I want to archive it!!

Thanks all for the progressive approach!

Hellfire 5'10
Weight approx 82kg
K2.1 quads
The feeling is in-between a quad and thrusters No other way to describe it
Some of the turns you can do has me smiling pretty hard

[core personal training]

danga....deviant is available through your local firewire dealer...you have to get one...works with any fins...in fcs it is similar in template to the 5's....read reviews on old forum for in depth info...but get one...

[prjwebb]

i picked one up the other day, going to try it in my Sub when the swell drops off a little.

Demoing a SP on tuesday :D

[Goanna]

I just ordered the knubster on ebay ($25 including postage) to try on my 6' Dom (goes good without it but I'll give it a go) then was reading the old forum ( hours of good reading there) when I read about the deviant fin for the thruster. Do these fins go any good? Where do you get them from and how much do they cost? I might get one and give it a go. What fins would go with it? I have G5's at the moment on my board. I also have M3s and FG-3s available from other boards. Would any of these go OK with the deviant fin?

Cheers.

Just get a Deviant.....they're real good

[Chris]

damn right

[Matt_s]

after looking at PRJs CIS link think im going to order the nubster with one of the following two set ups for my 5'9 el fuego and could also use on my 5'2 potato.

GAM - G1000 set up or an AM2 - GX set up.

Any thoughts at what might potentially be best for my weight (around 70-72kgs) in a 5'9 el fuego ?

I havent really experimented much with fins but I am enjoying my quad set of medium front and QM rear C drives (for those who have tried) and the SF4 quad set seem to go alright.

Thanks for any insight. I'l probably get the GAM - G1000's unless that would be unsuitable for my weight.

[Slowman]

after looking at PRJs CIS link think im going to order the nubster with one of the following two set ups for my 5'9 el fuego and could also use on my 5'2 potato.

GAM - G1000 set up or an AM2 - GX set up.

Any thoughts at what might potentially be best for my weight (around 70-72kgs) in a 5'9 el fuego ?

I havent really experimented much with fins but I am enjoying my quad set of medium front and QM rear C drives (for those who have tried) and the SF4 quad set seem to go alright.

Thanks for any insight. I'l probably get the GAM - G1000's unless that would be unsuitable for my weight.
I have a quad set of GAM/Q1000s and I think they're too big for you and unless the El Fuego is a very loose board they will make it too stiff. They were too stiff for my dominator.

I think AM2/GX would be better suited to your weight. I think they'll probably make the board feel more pivotal and add a touch more drive.

[core personal training]

just for reference, i jumped on a tiny 5'7 el fuego with futures yu's x 4...a small guys fin...had plenty for me to push against...and i'm 90kg...seemed to me to be a board you are pushing off a fair bit of rail so less fin (at least fin tip) needed...el fuego addicts may confirm this for us..

[Chris]

i'll need to try a nubby on that board....

[Matt_s]

I have a quad set of GAM/Q1000s and I think they're too big for you and unless the El Fuego is a very loose board they will make it too stiff. They were too stiff for my dominator.

I think AM2/GX would be better suited to your weight. I think they'll probably make the board feel more pivotal and add a touch more drive.

Thanks slowman, Il order the AM2/GX combo then, the el fuego is flat and I guess stiffer than something like the dominator. I thought that larger fins had more drive though? wouldnt having a smaller fin be creating less drive?

I was wondering do the back fins have any real impact on drive in a quad set up or is it really the front fins mainly contributing towards that?

Thanks again

Matt

[core personal training]

el fuego type boards get good rail drive too..so you dont rely on fins completely

[Slowman]

Thanks slowman, Il order the AM2/GX combo then, the el fuego is flat and I guess stiffer than something like the dominator. I thought that larger fins had more drive though? wouldnt having a smaller fin be creating less drive?

I was wondering do the back fins have any real impact on drive in a quad set up or is it really the front fins mainly contributing towards that?

Thanks again

Matt
large fins = more drive? Not really, in my experience the driviest fin I have is smaller than GAMs, it's my TC Redline. Things like rake and base length all have an effect. The GAMs have good drive because they have a rake of something like 36deg but that makes for a longer turning arc, a longer base can give more drive and combined with a more upright fin still give tight turning arcs (like the TC redlines do).

As for back fins, having an impact on drive in a quad set up, it's fair to say it does, but so do the front fins. I tried the GAM/Q1000 combination in my JS Kingpin and it was pretty good, so I thought I'd go for a bit more looseness with GAM/QR and it was loose but lost too much drive. So next I tried R2/Q1000 and also lost drive. So it's fairer to say you have to treat the combination as a whole and see how it works for you. The board of course, also has an effect on drive and looseness as Core pointed out.

[Slowman]

drat, double post

[Slowman]

I should add construction materials can make a significant difference to the same fin template as well. I reckon you should try glass flex fins as boomerangs and see if they're any good for hunting!

[hwork50]

Tried the nubster today on a 2-4 foot swell. Had a lot of stick on the face of the waves and was not very loose at all. I am not sure if I like it or not as I love my K 2.1 set up as a quad and this might make it stick a little more with the nubster in.

[Chris]

yeah work you could go smaller than the k2.1s or go with smaller trailers to try to loosen it up!!

Yeww!

[hwork50]

I think after surfing today with it 2-4 foot and no nubster I like it better without the nubster. I think if the waves get bigger then I will go with the nubster. (3-4 foot) Chris, what would be the next smallest size from the k 2.1's?

Brent

[saxman1]

I posted this in another knubster thread but thought I would share it hear too.

I just tried out a knubster on my 5'8" Dominator with the rusty R2 quad set. I wasn't 100% so I didn't get a full test. I had shoulder surgery in Sept and tore a ligament in my ankle in Dec. It was my first time out after my ankle injury. My ankle was a little tender so I didn't push to hard. I think in about two more weeks I will feel better about hitting the lip hard. I Did once but a bailed after I hit the lip because I didn't want to test my ankle that much yet. The shoulder feels good when I paddle. I have been good with the rehab.

I really liked it on the waves with a little more shape and size. On the smaller waves it did feel a little to stiff but I also felt week pushing my toe rail in because of my ankle so I know my transitions where not as fast as they could have been. It really did smooth the whole ride out. It made the board feel a little more locked in. I did a couple nice round houses and was generating a ton of speed. I did square off the bottom a couple times but I never really pushed it as hard as I usually do. It really feels like on a good wave you can really square of the bottom and get a nice smooth wrap. I just have to see if I like how it releases. It will be a couple of weeks before I really know how it releases with harder surfing.

I would say that so far it is an improvement on chest to a little overhead size waves with my R2 set. I will try putting some smaller quad trailers in with the knubster and see if it feels better on the waist/ribcage high stuff. Chest high to overhead it feels great to me so far. I'm thinking of having one plug put in my old quadraflex so I can use my Knubster on that board.

[Muz74]

Try two stabilizers (or knubsters/cutdowns) where the quads would be with a MR TX trailer in the rear, M5's up front. Fast and ridiculously loose in the small stuff!
Seriously good fun.

[Muz74]

403

Fun set up for 3ft and under, the 2 little stabilizers stop it spinning out with the MR TX trailer.

[Slowman]

Tried the nubster today on a 2-4 foot swell. Had a lot of stick on the face of the waves and was not very loose at all. I am not sure if I like it or not as I love my K 2.1 set up as a quad and this might make it stick a little more with the nubster in.
I thought you bought a Rainbow 5th Finner, they are a slightly different shape and the dimensions differ slightly too. For side by side comparison:
405 406
My experimentation with these things found the shape did have quite an impact. The other thing is you have 2 position options. I believe the 5th Finner is longer in the base and also with that rake would probably be a bit stiffer and might be worth moving it to the forward position to see if that changes anything (assuming you tried it in the rear position).

Muz that truly is a 5 fin set up....funny I don't think of the quad with a stabiliser as 5 fins I still think of it as a quad (but with help). However others are saying I'm riding with 5 fins...I must be in denial

[cuttlefish]

Classic...I just posted up a bunch of photos of combos I'm going to try with my Potatonator with Futures fins on the "Potatonator small wave assasinator" thread that you may y'all want to look at since the Potatonator is the Dom's wild half breed cousin.
Too bad my Poatonator is Future's shod otherwise I'd have a set of FCS GRV's (the crazy curved fins) in it straight away.

[saxman1]

403

Fun set up for 3ft and under, the 2 little stabilizers stop it spinning out with the MR TX trailer.

Have you tried this set up with out the little side fins. Just asking because it looks much more like a thruster than a quad. I was wondering if it still has that quad out of the gate speed. I need to post some pics of my recent experiments.

[iggy]

Humm, interesting

[Muz74]

Have you tried this set up with out the little side fins. Just asking because it looks much more like a thruster than a quad. I was wondering if it still has that quad out of the gate speed. I need to post some pics of my recent experiments.

I tried this set up because I found that the quad was super fast but not as reliable turning and the thruster turned ok but lacked the speed. I have found this set up gives me the best of both worlds. I had this set up in another fish with a wide tail and it works well. Hey its all about fun and experimentation, ive just put PC7s thrusters in and they are alot faster than the M5s I tried originally.

[Muz74]

Oh, I have tried it without the little side fins. Too loose. Spins out.

[saxman1]

I tried this set up because I found that the quad was super fast but not as reliable turning and the thruster turned ok but lacked the speed. I have found this set up gives me the best of both worlds. I had this set up in another fish with a wide tail and it works well. Hey its all about fun and experimentation, ive just put PC7s thrusters in and they are alot faster than the M5s I tried originally.

That's freeking cool man. It looks like it would just cause drag but you never now until you try. I used little twinzer fcs side fins with the Rusty fronts and the knubster in small waves. In the little stuff it felt pretty good but as soon as the waves got a little better and bigger I needed more bottom turn squirt. I put the complete rusty quad set back in with the knubster and I really liked it. I think the issues I had with it before had more to do with my ankle not being 100%. With my ankle being much stronger now I really felt good even on the smaller waves. Anything over chest high and it felt just amazing. I was doing really hard bottom turns and hitting the lip hard. The set up worked great. I can't wait to try it again. I'm going to get one center FCS plug put in on my quadraflex just for my knubster.

[Chris]

i like the baby quad trailer thruster set. tell slater.

[Muz74]

NO! Tell Taj! Hahahaha!

It may not work for everyone but I have fun with this set up in tiny surf. This set up probably has the same fin surface area as a regular quad set up. I'm not a scientist but experimenting with fins is something everyone should try, it gives you a few different options for the one board and keeps the stoke alive.

[Muz74]

Must add some info here, after going for a surf in pretty fat small waves yesterday this set up didnt feel so good, so I would have to add small sucky waves are best for this set up.
I also tried SF4'S with a knubster in the same surf and it felt pretty stiff.
Will try the SF4's again with the knubster in something bigger.

[Chris]

for sure Muz. I rode the knub in soft surf and hated it. better when the wave has better shape and you have ample speed. if you have to generate speed in small surf, the drag isn't worth it.

[Muz74]

Today's quad set up, PC7's at the front with some old GL's in the rear, went unreal in 3ft fat waves.

[saxman1]

Hey munz74, would you say the little rear quad fins add any speed to the set up u posted that looks like a thruster on roids? It makes me want to try my Rusty thruster set with little twinzer front fins in the rear quad position.

[spawne]

Love your work slowman,
I think I will do the same. Bourton shapes (murry bourton) has his own personal fins as well, one for the quads and one for wide tail thrusters. More like your first one, worth checking out. Also how do the rusty fins go? Can you compare to any other fins?

[Slowman]

Spawne, I find the Rusty quads fast, loose and have good drive. Looser than a GAM/Q1000 set and probably a tad faster too. The GAM/1000 have good drive and great release off the top and so do the R2s. The GMB ("Mayhems") quads are a tad looser than the GAMs and with perhaps a touch less drive. They also use a rear 80/20 foiled Q1000.

I have a JS Kingpin which I originally put the Rustys in and the board was insanely loose but lacked any drive whatsoever, one of the best days of the year and I took my new kingpin out and after every turn I almost stopped dead in the water...so that is why I ended up getting a GAM/Q1000 quad set. I got some drive back and it was still loose, but this combination was way too stiff for the dominator so that is when I tried the R2s and it all seemed to click a bit more and then with the little stabiliser, voila, it finally went how I wanted.

I've also tried the K2.1 quads (also use a rear Q1000 but flat foiled) and they were fairly similar to the R2s with a touch less drive and speed I think but were pretty close in feel. I haven't tried any others the R2s seem to work really well for me. I use them in my spitfire and my hellfire too.

[spawne]

Slowman, Sorry if that first part of the question was a bit hard to understand, but just joined. I was referring to the stabilizer fin. Have you tried the knubster to you home made fins as they seam to sit futher back or forward then yours in the thruster position? I have a Dom which I love, but dont surf that much, and at a intermidate level. I am starting to link relaxed turns when my feet are in the right position. Would the helfire take a few waves to get used to each surf compared to your kingpin? Both boards I was considering for bigger wavers.

[Slowman]

Spawne, no never tried a real knubster. The hellfire had quite a familiar feeling and didn't take much getting used to as I'd ridden boards that felt quite similar (bat tail quads with single to double concave) but I suppose coming off the king pin it wouldn't take too much either. The king pin is very loose but has less rocker than the hellfire but still enough to be able to drop in pretty easily on steeper waves, though the hellfire is even better.

[Muz74]

Hey munz74, would you say the little rear quad fins add any speed to the set up u posted that looks like a thruster on roids? It makes me want to try my Rusty thruster set with little twinzer front fins in the rear quad position.

Yeah Saxman1, this set up is giving me the best of both worlds, the speed of a quad with the pivot of a thruster. Good fun. Although, this didnt work so well in waves that were fat, neither did the quad (sf4) with knubster. Sucky waves were great though.

[Fritzkat]

Ok, testing a Stubby fin I made out of an old Futures TP-1 rear composite fin.

My guess is that everyone is saying to use it in average to good conditions in a Quad fin with smaller rear Quad trailers, Pointless to have in crappy Bouncy muchy foamy surf, as the fin will not catch in foam and will only drag between the transitions. So, my first test will be with (all Futures) AM-2 fronts 4.79" and combo with V2F4 3.75" rears. I figure on down the line hollow surf head high +
then the AM-2 fronts 4.79" with Quad 3.40" on playful glassy peaky waves that like cutbacks to Shoulderhigh
then the AM-2 fronts 4.79" with Rusty Rears 3.85 on playful glassy peaky waves that like high snaps and cutbacks to Headhigh

I dont think that I will try anything larger like the larger Stamps 4.0 rears as it would be too much hold and not loose enough, unless the waves are cranking. ANY THOUGHTS ON THIS FIN AND WHAT TO COMBO WITH???
Oh and I will be using with my Hellfire, Dominator and the Activator
...th Snubster
769

AM-2 fronts (4.79) with Rusty Rears (3.89) & V2F4 (3.75") rears & Quad 3.40"
770

[Slowman]

Fritz, I found that certain shapes reacted badly in bouncy conditions - in particular the first one pictured on p.1 "the slug". I found with enough gradient and curve on leading or trailing edges it helped make the fin's effect more gradual as it "popped" out of the water as you bounced over lumps, so you didn't suddenly lose all the surface area instantly. Anyway I still use mine in crap or good waves and it still works better with than without. Yours looks curvy enough to work in chop too. Even a straighter edge with a good gradient would do the same.

I just took my dom out with a set of FCS SF4 quads with a "stab" and they all worked well together, probably as good as the R2s with a tad more looseness, though I used a larger stab to compensate for the loss of drive over the R2s.

[Fritzkat]

Just tested the Snubster I made on my 6-4 HellFire with AM-2 fronts 4.79" and combo with V2F4 3.75" rears. Head High day. ( had a kink in my neck so I was not as loose as I wanted to be,) However. there did not seem to be any noticeable drag and there was a bit more hold, board was reactive during a carve with little or no sliding sideways. Good hold. Neck started bothering me so I could not retest with out them in the box on those same waves.
781

[Slowman]

I've been using a few different stabs...I think I have got it to the point where I can more or less use them to "tune" the board and quad set to the characteristics I want.
788 Hellfire with FCS R2 quads and small stabiliser
789 Hellfire with FCS H3 quads and small stabiliser (too stiff)
791 Spitfire with FCS R2 quads and medium stabiliser
790 Dominator with FCS SF4 quads and larger stabliser

[prjwebb]

Nice DIY work! I'm a fan of the Nub in my Spit. Looking forward to trying it in the Minnie when it comes.

[Fritzkat]

Slowman, those large base fins in the back, they look really stiff, have you tried a smaller sets in the back? Just curious.

[Slowman]

Fritz, it's just a bit of an optical illusion, they are quite small relatively speaking. Roughly the front ones have around 9700 to 9800 squ mm of area and the rears are around 7500-7700, compare that with the Q1000 (K2.1 quad rears) which are 8158 mm**2. The Simon Anderson quad rears are humungous by comparison.

[Chris]

you know...some folks have turned the deviant into a knub. Have to say, I am keen to try that!!

[prjwebb]

interesting.... where's that dremel tool....

[Slowman]

you know...some folks have turned the deviant into a knub. Have to say, I am keen to try that!!
Interesting. There wouldn't want to be much friction in the pivot, or else with less surface area it might be a bit slow to change slant. I'll get around to playing with one one day.

In theory it seems to me that there would be less advantage to a deviant knub. To my way of thinking the deviant is attempting to give a thruster set up some of the advantages of a quad, such as more hold on the active rail and speed. Whereas the stab/knub is trying to give some of the advantages of the thruster to a quad set up, like pivot and directional control. However, after all is said and done the proof is in the pudding.

[Slowman]

Sorry about the double post, I'm currently in Taiwan and connected through some nearby unsecured wifi...it's just a little flaky ...


you know...some folks have turned the deviant into a knub. Have to say, I am keen to try that!!
Interesting. There wouldn't want to be much friction in the pivot, or else with less surface area it might be a bit slow to change slant. I'll get around to playing with one one day.

In theory it seems to me that there would be less advantage to a deviant knub. To my way of thinking the deviant is attempting to give a thruster set up some of the advantages of a quad, such as more hold on the active rail and speed. Whereas the stab/knub is trying to give some of the advantages of the thruster to a quad set up, like pivot and directional control. However, after all is said and done the proof is in the pudding.

[Huyseman]

Does anyone know what fins are the blue ones - not the K2.1 as shown in the other picture..

900901

[prjwebb]

Fibreglass K2.1s rather than Performance Core I think.

[Huyseman]

Fibreglass K2.1s rather than Performance Core I think.

I don't think so... ;)
The fiberglass K2.1 have the white circle and the model written

903

[Huyseman]

Fibreglass K2.1s rather than Performance Core I think.

I think you were right :)

904

[prjwebb]

They are the FCS Prototype fibreglass material I think.
When Kelly won his 7x title FCS released 3000 Fibreglass k2.1 sets so you could try and track some of those down.

[Slowman]

Those fins look like solid fibreglass for certain and I don't think the K-flex was fibreglass, more some kind of rubber/plastic. I was going to say PG5s but they don't even have a logo on them. Hard to say but the template looks similar to me...
905

[Chris]

the other thing to note is that just putting any quad set in with a knub won't equal the same thing on all boards. Notice how far back and how close to the stringer Kelly's trailing quad fins are. That creates a much more thruster like feeling than something like a potatonator which has the trailers a little further out towards the rail.

It will take a little experimentation to figure out which quad set works best with the knub i feel.

[DGR]

I am enjoying my nub on and off on my spitfire. I am riding with MF1 fronts and SXQ rears(shapers version of gxq). Without the Knub I find this set up super fast and fun.
With the nub the board definitely feels slower and a bit draggy, especially noticeable in fat waves. In powerful waves though I really like the feeling through top turns, it sort of helps you push back into the wave faster. While slower than just the quad it is still and looser and faster than a thruster. I will keep using the nub in preference over the thruster for more powerful waves on the spitfire in future

[Huyseman]

Those fins look like solid fibreglass for certain and I don't think the K-flex was fibreglass, more some kind of rubber/plastic. I was going to say PG5s but they don't even have a logo on them. Hard to say but the template looks similar to me...
905

I believe they are prototypes - here's a screenshot of Kelly changing his fins in US Open

918

[jus]

919
My Futures attempt at a fifth fin on hellfire - I just cut it to match futures box so not sure if it is forward or back of where and FCS version would sit. Anyone have any ideas about the placement

[Slowman]

Jus, looks good to me, looks roughly the same as my placement using a cut down FCS MR TFX fin.

[luismx]

1547

My home made Woodster! :D

[Slowman]

yew, saving that for a technograin spitfire?

[luismx]

going on my dom + Hellfire/unibrow :D