Select to expand quoteOla H said..
But theory aside, as commented above, when the front fins is a bit bigger toe in need to be within half a degree or so to avoid draggyness or (risk of) twitchyness.
Impressive. Nobody can argue against your opinion, and if this is what you and other "pro" surfers feel fine. And I am very happy for you and your customers.
But with your science background you are aware that a fin has only lift and drag forces as the physical relevant aspects to it.
The relationship between AOA and lift and drag for foils is very well experimentally established. And these forces are very steadily with the AOA. So no abrupt jumps until it stalls.
But from what I read from your statements is that even a tiny wrong angle does make a hugh difference, like the board turns or does go straight.
So what I do not understand is how can the behaviour of something change abruptly if all forces applied to it don't. So it seems like physically there is a transition from one state to another. Like a phase change for ice to water. Which is only an analogy. Which is the only reason for abrupt changes.
Nowhere else in the area of fluid dynamics this phenomenon of a state change was observed to my knowledge. And turning a surf board can not be so different than flying with a plane a turn.
But hey all this is only just physical reasoning and not relevant. Because you can feel the difference if you are skilled enough. Which is a very good argument. And I am only a mere mortal with decent wave sailing abilities.
But somehow it reminds me on an interview which Patrick Diethelm once gave in the Windsurf Journal in 2008 I think. There he told a story of one of his riders, who was very unhappy with the board. Patrick took it sanded it and painted it new and gave it back to the guy. After that it was the best board. Since I read this I personally have my opinion on "feeling". And as I already assume some people will tell me I should shut up because I do not believe in it, and my sailing abilities might be not good ennough to be allowed to have an opinion, I think this is forum were everybody is entitled to add his opinion on a topic, no matter if you like it or not.
Select to expand quoteSchobiHH said..
Impressive. Nobody can argue against your opinion, and if this is what you and other "pro" surfers feel fine. And I am very happy for you and your customers.
I'm not at all saying that there is a discontinuity involved, just that all interesting stuff happens within a few degrees of difference as far as toe in goes. Surely between 0 and 4 for a symmetric front fin in a typical placement as far as draggyness in a straighline goes.
The fins in fact makes up quite a bit of the drag of the whole board. This is why it feel magic to ride a speed board when a dedicated super small speed fin, as opposed from a slalom fin. More fins add more drag and with side fins the board cant autoadjust in the same way as with a single fin. So drag is gonna matter.Select to expand quoteSchobiHH said..
But from what I read from your statements is that even a tiny wrong angle does make a hugh difference, like the board turns or does go straight.
No, not like that. What I said was that _for me_ at some point if feel drag coming into play and I don't like that feel so I want less toe in than that. And from the other side, I prefer a little toe in because of how toe in changes bottom turn initiation. The inner fin, in particular if it is relatively powerful play an important role in a turn. And because of how turning dynamics work (Bouke has it explained in the thread) toe in will in practice affect the "time of engagement" for the inner front fin. More toe will very slightly but importantly let the board roll a little bit more into the turn (and let the tails start to slide out just a little bit more) before the inner fin starts to generate lift to stop the tail from sliding further. And the most important "turning error" a (good) sailor makes is to push the board to hard before it has settled into the turn. On a multi fin board more toe in angle means this happens a bit more seldom. (And recall, even the best surfers one their most trusted boards at, say, Jaws, have it happen to them so it will always happen not and then, it more about making it happen less. And of course the same thing happens often on single fins too, it is not a front fin issue as such.)
I set my toe in to compromise those two aspects drag and turn entry feel. Luckily it seems to exist a good compromise, and Bouke-style theory supports it.
In general I feel this is a bit like the edges in a top level prepared slalom ski. Of course you feel the difference between a 0 and 1 degree hang angle. Select to expand quoteSchobiHH said..
So what I do not understand is how can the behaviour of something change abruptly if all forces applied to it don't.
Again. I'm not saying it does. Select to expand quoteSchobiHH said..
But somehow it reminds me on an interview which Patrick Diethelm once gave in the Windsurf Journal in 2008 I think.
I remember this story. It can happen. So it is very important to try to have all your riders report without prejudice. And as far as yourself go you need to work all the time to minimize your biases. This is in fact why I downplay theory in discussions like this. I like thinking theoretically... and discussing too. But in the end the issues are theoretically complex and theoretically misunderstood, so you must always confirm with what sails well.
Select to expand quoteOla H said..SchobiHH said..
Impressive. Nobody can argue against your opinion, and if this is what you and other "pro" surfers feel fine. And I am very happy for you and your customers.
I'm not at all saying that there is a discontinuity involved, just that all interesting stuff happens within a few degrees of difference as far as toe in goes. Surely between 0 and 4 for a symmetric front fin in a typical placement as far as draggyness in a straighline goes.
The fins in fact makes up quite a bit of the drag of the whole board. This is why it feel magic to ride a speed board when a dedicated super small speed fin, as opposed from a slalom fin. More fins add more drag and with side fins the board cant autoadjust in the same way as with a single fin. So drag is gonna matter.SchobiHH said..
But from what I read from your statements is that even a tiny wrong angle does make a hugh difference, like the board turns or does go straight.
No, not like that. What I said was that _for me_ at some point if feel drag coming into play and I don't like that feel so I want less toe in than that. And from the other side, I prefer a little toe in because of how toe in changes bottom turn initiation. The inner fin, in particular if it is relatively powerful play an important role in a turn. And because of how turning dynamics work (Bouke has it explained in the thread) toe in will in practice affect the "time of engagement" for the inner front fin. More toe will very slightly but importantly let the board roll a little bit more into the turn (and let the tails start to slide out just a little bit more) before the inner fin starts to generate lift to stop the tail from sliding further. And the most important "turning error" a (good) sailor makes is to push the board to hard before it has settled into the turn. On a multi fin board more toe in angle means this happens a bit more seldom. (And recall, even the best surfers one their most trusted boards at, say, Jaws, have it happen to them so it will always happen not and then, it more about making it happen less. And of course the same thing happens often on single fins too, it is not a front fin issue as such.)
I set my toe in to compromise those two aspects drag and turn entry feel. Luckily it seems to exist a good compromise, and Bouke-style theory supports it.
In general I feel this is a bit like the edges in a top level prepared slalom ski. Of course you feel the difference between a 0 and 1 degree hang angle.
Very well said, sometimes it is not easy to describe these things in words.
Remember SchobbiHH , your so impressed with how your multifin production board runs - that you have gone back to using it as a single fin ! - if that is not a self defeating arguament confirming real life bias experimentation - I dont know what is ? (btw - If you like that feel - I run a 78ltr with largish rear (for me ) and smallish toed canted fronts (7's) - ie REAR CENTRIC setup TRIFIN setup ,,,,, and I love that singlefin esq hook off the top - and general pitch in turns - gives alot to push off .... really good for say Peaky reef break ....
Ive also had really fun sessions with Bottom turn inner fin aggressive toe- say 4.5 deg , and topturn Heal fin say 3 deg - on starboard tack I get a really grippy vertical bottom turn - and off the top -more ability to hold a more drawn out carve .... I ran this a few years ago - and has reminded me to try again ....
science is fantastic SchobiHH
You may find this study interesting as for me it counters some of the stuff written previously in this thread.
the whole thesis is a great read.
Select to expand quotesheddweller said..SchobiHH said..
That is excatly what I was talking about. I do not understand why you make them confidential. The only reason I can see is, that you fear that it has not the convincing results as you mention.
And when I see the pic from above as part of the results then I have some idea of the quality.
So this guy invests in a business, spends years learning how to do it, buys machines and tools, employs people etc
Then when he does some work on the detail design of his product you think he should be publishing that data for all to see just so he can convince a few bored ****wits on an internet forum? Are you joking?
This whole thread is bizarre ... And I think some in glass houses throwing alot of stones ( Dont make me post a pic of how to put on pads that TOTALLY f%^ck up rail flow !!!!!!!!) .... there's alot of 'jesting' / calling out / princess purse etc - and then when someone does - it gets fired back at them for 'posting flashy pictures proves nothing ' or surely a research paper was published - wtf ...
I think anyone here suggesting TOE has merit / IS the way forward ..... is offering advice for FREE - to HELP OTHERS THAT MAY BE STRUGGLING , based on countless hours of experimentation , fin tweaking , with LOTS of prototypes / shapes , that weekend chargers havnt the time / money (for trying many different boards ) or conditions / resources to experiment ... and in that light - its how the observations should be treated .. Geeez man , OLa and BOUKE are giving alot of free advice based on ALOT of experimentation ..... (and I dont feel its about pushing product / ego - Bouke could just shut up shop on forums and let the production NON TOE guys keep duping the general public year after year with suboptimal performance ) . He's acutally doing himself / his brand a disservice by voicing all this insight ...
If ordinary punters are happy with NON OPTIMAL turning performance on their waveboard , doing grubby's on the face everytime they push it fractionally harder - thats up to them .... If you buy a waveboard to sail around fast , at the expense of what its actually designed to do (ie waveride) - then you might as well jump on an FSW and have all the drag free speed you want ... (in singlefin if you want for ultimate drag free riding ...)
THought experiment - if you decide your waveboard feels draggy with TOED fronts - maybe it means you can transition onto a faster rocker than your current board - and add TOED fronts - and STILL get really good turning equal to your older board - and that extra speed the faster rocker delivers .... ???
Most of the high level sailors in the world are using TOED fronts ... LEVI , BRAW , KT (designer ) CAMPELLO , SWIFTY (tectonics) , PARE , JUBAN , BERND (flikka) , LEON (flikka) , SIMMER guys - ALessio , OLA simmer designer ..... Ezzy / TRAVERSA - (k4 converting prod straight boxes , Bouke / witchcraft / all his local high level riders , ALL the k4 pro riders , so its hardly 'NICHE' - among the upper echelons - yet its FAKE NEWS ...... bULL**** among everyone else ? ...
I think the stone throwers - are restricted in their approach / bias - by local (****ty side on ) conditions .... YET for me - I would still way sooner ride TOE in / assy fins in side-on .....
Guess it depends on what you wanna read. As it stands boukeke has said most of the sailors on your list are riding poorly designed sub optimal boards with fins that dont work.
Lol.
Select to expand quoteSchobiHH said..
But somehow it reminds me on an interview which Patrick Diethelm once gave in the Windsurf Journal in 2008 I think. There he told a story of one of his riders, who was very unhappy with the board. Patrick took it sanded it and painted it new and gave it back to the guy. After that it was the best board. Since I read this I personally have my opinion on "feeling". And as I already assume some people will tell me I should shut up because I do not believe in it, and my sailing abilities might be not good ennough to be allowed to have an opinion, I think this is forum were everybody is entitled to add his opinion on a topic, no matter if you like it or not.
I don?t remember that but I can imagine it. The mind can really play tricks on us. I have had customers or team riders going from this board is sh!t to the best board ever from one day to the next just because on the first day, the conditions didn?t suit at all and got the set up wrong all together. And most PWA riders are just as biased as any of us, if not more. They are a bit in a bubble and most will be looking at what the guys higher in ranks is using. When Federico Morisio rented gear of me for 10 days last june (by the circumstances he was forced to), he kept the gear for one day longer after his own gear had arrived, to test it against eachother to check if it was not his mind playing tricks. He is the only one of the PWA who tested my fins/whole gear and besides him, only very few may have even heard about them for reasons given earlier. But of course these guys have to promote their sponsors. What was that saying again? Whos food you eat, whos song you sing?Usually when I want Will or Yannick to test something, I will think of an excuse like "your fins look a bit damaged, I will give you some new ones. When I gave Will the first pretwisted fins, I said to him, see if these turn better. Which they should not as the average toe in was the same and the rest was the same as well, the only difference was the pretwist. When he came back he said: I don?t really think they turn any better, not worse but not better either. I said no? OK. And then he said, by himself: But they did feel smoother somehow, like keeping speed better. It was a pretty light float n ride day with 2m clean waves. And yes, like Ola said, the fins make up a decent part of the drag. Even if tail kick also feels like sailing with the hand brake on when winds are light.
The locals here dont really pay attention to the PWA, I bet that 80% dont know who is the current world champ nor who won Cape Verde, I dont even know who is at the moment. They are capable and get enough good days to decide for themselves what works and they also need to see what lasts when you have to pay for the gear instead of getting it for free.
^^ Totally opposite to you previous posts. All your stuff is how it totally transformed the guy's ride immediately!!!! A handful of guys and here is a big aerial pic to prove
Troll.
Ridiculous POV. At least Seabreezer will buy a set of fins of 6 from you.
Select to expand quoteMark _australia said..
^^ Totally opposite to you previous posts. All your stuff is how it totally transformed the guy's ride immediately!!!! A handful of guys and here is a big aerial pic to prove
Troll.
Ridiculous POV. At least Seabreezer will buy a set of fins of 6 from you.
6 fins, one board? Yahoooo, now we're talking, please build it Mark. The possible rhetoric about VMG/angle of attack X apparent cavitation on my asymmetric sub-surface twisted tips would continue longer than the heat death of the universe!
Editors note, I like twinnies more and more the longer this thread goes on.
Select to expand quoteMark _australia said..
^^ Totally opposite to you previous posts. All your stuff is how it totally transformed the guy's ride immediately!!!! A handful of guys and here is a big aerial pic to prove
Troll.
Ridiculous POV. At least Seabreezer will buy a set of fins of 6 from you.
who is the troll?
You are picking up on one particular aspect and using that as a reason to disregard everything.
there are many reasons to doubt boukes stuff, but your reasoning has been misplaced a couple of times ( i could be wrong- this is my reading of the thread)
So my interpretation of above- bouke is talking about pretwist only- not about toe, the pretwist is a refinement of the toe and will allegedly lead to a refinement of performance, not a transformation.
The transformation was the complete system and not the one detail aspect.
Also with regard to your "grain of sand" 0.1 degree toe claims. These are disingenuous as well ( in my view) what bouke said was that he will adjust toe by 0.1 degrees when designing boards. to which you call bull****. I design things every day for my work, when i design things, i use what i think are the optimum dimensions, sometimes the dimensions could be different and make no difference but if i have an optimum in mind why would i not use that at the design stage? What you are suggesting is that bouke should have an optimum in mind and then NOT utilise it in a "no cost" implementation scenario. pretty silly.
( full disclosure, i don't use boukes fins, i have tried them and i prefer k4 ezzys)
Select to expand quoteBrent in Qld said..
Editors note, I like twinnies more and more the longer this thread goes on.
They can have toe in too. You need to go single.
Select to expand quoteMark _australia said..
^^ Totally opposite to you previous posts. All your stuff is how it totally transformed the guy's ride immediately!!!! A handful of guys and here is a big aerial pic to prove
Troll.
Ridiculous POV. At least Seabreezer will buy a set of fins of 6 from you.
What is totally opposite? May be you need to learn to read and think it through rather than raging like a bull for a red rag? In my post, I mentioned the difference in drag and feel of ONE change: from asymmetrical toed in fins to pretwisted asymmetrical toed in fins in the same size. Pretwisted being the ONLY difference. When testing stuff you should only do one change at a time, otherwise you do not know what change does what.But when for example people who used the standard paralel symmetrical 11cm side fins and a 20cm centre fin went to my pretwisted fins of 13.5 and a 14cm centre fin, there are 5 changes all at once, which took me 17 years of development and then indeed it transformed the ride immediately:
1. Toe, allowing for:
2. equalished sized fins (especially the much shorter centre fin makes a big difference)
3. asymmetrical profiled fins (which give more grip and allow/need more toe which gives more drive)
4. pretwisted fins (which, added to the above, reduces drag, especially when using bigger side fins)
5. All 3 fins with the same (more wave orientated) profiles and with twist (raked back) that gives more predictability, reliability and drive.
Capiche?
Select to expand quoteOla H said..Brent in Qld said..
Editors note, I like twinnies more and more the longer this thread goes on.
They can have toe in too. You need to go single.
In the 90s when testing with twins to improve the predictability, I moved the fins closer together as well but with less than 12cm it felt like they were interfering with eachother causing more drag and then I tried with a tiny bit of toe and that improved. The general rule surf board shapers use to point all fins to the nose or a little bit in front of the nose, makes sense. Maybe it can be refined but it is more or less like that.
Select to expand quoteBouke as soon as anyone questioned you, you said people get on the board and can immediately feel it's different and better. That's your proof.
After all this arguing somebody mentioned Patriks experience where he changed nothing and the guy loved the board suddenly as he thought it was different
You agreed that happens a lot. Just the opposite of what you have been saying to prove us all wrong so yeah it looks like a troll.
As to this 0.1deg I challenge anyone to feel that change.
CNC blah blah - but it is the thickness of one layer of glass around the box so a wrinkle in the glass during install would move it that much.
No person in their right mind would agree that changing by 0.1 is worthwhile
Even Ola says about half deg maybe
The discussion about toe is valid but bouke you need to take the salesman hat off to do it.
Select to expand quoteMark _australia said..
^^ Totally opposite to you previous posts. All your stuff is how it totally transformed the guy's ride immediately!!!! A handful of guys and here is a big aerial pic to prove
Troll.
Ridiculous POV. At least Seabreezer will buy a set of fins of 6 from you.
I would love to have a set of Boukes fronts , in slot and US .... and really try to get that true THRUSTER set up working ...Ive tried with 12/14s fronts other style of assy fronts .... BUT ... I have a suspicion that bigger fronts could ? become a handlful in overpowered side off conditions .... (but maybe countered by the smaller rear adding. some nose down control - I don't know ) ..... I know what Ive got right now (toed and CANTED fronts - quads 15.5/8's , or trifin 16.5/8s or 10's work pretty good overpowered , arc adjustability etc etc
BUT - I also watched alot of Kai Lennys aloha heats with his 'true' thruster set-up (TOED fronts , similar size rear etc) .... and I think it cost his heat progress in semis and finals - he would land moves - and where a 'rear' based setup of say quads 14/15 and 10's would grip and help recovery - he was spinning out landing heavy from aerials and goiters ... and losing scores .... so that was a downside of equal sized setup - he would have for sure been running 3deg TOE and assy ....
Mark - for sure talk of 0.1 / 0.3 deg is a little OTT - BUT - if your middle value tolerances are that tight - any deviation in production likely to be fairly / really tight .... so its a fair pot from Bouke ... I wouldn't wanna be , for instance , padding up someones board with ridiclously thick pads extending right out into the rail line - which would surely fck up rail flow when heavily engaged bottom / top turn .... throwing all sorts of spanners in the works - and let that leave the workshop ... EVEN If someone brings in toooo thick pads - maybe there's the slight scientific paper argument they need to be sanded WAY way way down at edges to not affect that rail flow ???.... ! this is where Boukes 'tight' tolerances won't allow 'random ****' to happen ! ...... fair point ?
I'll be dammed if I'm reading any of this fin sci-fi dribble. witchcaft boards go bloody good, the whole package, rail rocker and fins. Definitely better than the production boards I've sailed. Planes quicker and rail turns so good. Cross- Onshore was where it was super obvious, and I can't sail onshore at all.
the fancy witchcraft fins in my Quatro do some weird stuff bottom turn at speed on big waves, like eat some major sh!t weird. But turn sick in small slower stuff
assy have to be the go, wavesailors want to surf, no surfboard has straight symmetrical fins.
i recon Bourke is on to something, just felt right on his board, and haven't felt that on my own gear.
you can knock it but it works, but may not be Isolated to fins though.
Select to expand quoteMark _australia said..Bouke as soon as anyone questioned you, you said people get on the board and can immediately feel it's different and better. That's your proof.
After all this arguing somebody mentioned Patriks experience where he changed nothing and the guy loved the board suddenly as he thought it was different
You agreed that happens a lot. Just the opposite of what you have been saying to prove us all wrong so yeah it looks like a troll.
As to this 0.1deg I challenge anyone to feel that change.
CNC blah blah - but it is the thickness of one layer of glass around the box so a wrinkle in the glass during install would move it that much.
No person in their right mind would agree that changing by 0.1 is worthwhile
Even Ola says about half deg maybe
The discussion about toe is valid but bouke you need to take the salesman hat off to do it.
I did not agree it happens a lot but that it happens. And I am aware of it. Those who tried the fins in other brands boards and as such had the biggest change all together, are obviously not Witchcraft fans, neither do they have to please a sponsor. The one local guy with a Pyramid came in because he was not happy with his board and he had seen on Facebook that I had been adapting fins for another Pyramid and he wanted to know what it was all about. As a set of fins plus modifications isnt cheap, he was still a bit hesitant. So I said, I will make the fins and if you keep them clear of the rocks I will give you your money back if you do not like it. And the difference was visible from the beach. In summer we get spells of very similar conditions every day at our summer time side shore spot Glass Beach. I had seen him struggling before and I was interested how he would do so kept an eye on him. But then he was sailing well. And when I spoke to him weeks later he said literally: Unbelievable.
Select to expand quoteDunkO said..
I'll be dammed if I'm reading any of this fin sci-fi dribble. witchcaft boards go bloody good, the whole package, rail rocker and fins. Definitely better than the production boards I've sailed. Planes quicker and rail turns so good. Cross- Onshore was where it was super obvious, and I can't sail onshore at all.
the fancy witchcraft fins in my Quatro do some weird stuff bottom turn at speed on big waves, like eat some major sh!t weird. But turn sick in small slower stuff
assy have to be the go, wavesailors want to surf, no surfboard has straight symmetrical fins.
i recon Bourke is on to something, just felt right on his board, and haven't felt that on my own gear.
you can knock it but it works, but may not be Isolated to fins though.
I was wondering how you were getting on with them. More recently I realised I place the fins closer to the rail (to make more use of the drive effect when the outer fin leaves the water so you can crank it through a turn harder and also to keep grip better when you are hanging in the wall) and that for boards with the fins more in board, maybe could use a 0.2 or 0.3 degrees less. I will change that next time. But as you say, in smaller waves they work well and that is what most people have.But if the wave goes too steep at some point you will lose the tail though:
Select to expand quoteBouke-Witchcraft said..
But if the wave goes too steep at some point you will lose the tail though:
that wipeout hasnt got anything to do with fins- the wave caught his clew.
Well I've now caught a clue, this thread has educated me and I'm all toed out from reading it.
Select to expand quoteBouke-Witchcraft said..DunkO said..
I'll be dammed if I'm reading any of this fin sci-fi dribble. witchcaft boards go bloody good, the whole package, rail rocker and fins. Definitely better than the production boards I've sailed. Planes quicker and rail turns so good. Cross- Onshore was where it was super obvious, and I can't sail onshore at all.
the fancy witchcraft fins in my Quatro do some weird stuff bottom turn at speed on big waves, like eat some major sh!t weird. But turn sick in small slower stuff
assy have to be the go, wavesailors want to surf, no surfboard has straight symmetrical fins.
i recon Bourke is on to something, just felt right on his board, and haven't felt that on my own gear.
you can knock it but it works, but may not be Isolated to fins though.
I was wondering how you were getting on with them. More recently I realised I place the fins closer to the rail (to make more use of the drive effect when the outer fin leaves the water so you can crank it through a turn harder and also to keep grip better when you are hanging in the wall) and that for boards with the fins more in board, maybe could use a 0.2 or 0.3 degrees less. I will change that next time. But as you say, in smaller waves they work well and that is what most people have.But if the wave goes too steep at some point you will lose the tail though:
Bouke ..... bit more CANT ? .... ( i love it - know you would sooner leave vertical forces alone )
