sheddweller said..
Bouke, how much more or less toe do you use with different bottom shapes, say monoconcave all the way through or v all the way through?
And do you put all the toe in the fins or some in the box and some on the fin base?
Picked up some of your twisted fins ( early red ones semi transparent not that tough, not g10) and was going to try them in my board but not sure how to work out how to grind off the mini Tuttle base for the best angle in the slot box.

The difference in flow deflection between a concave and V is not that big, about 0.3 degrees at the bottom so an average of 0.15 over the depth of the fin. Since I was using toe with symmetrical fins at first, I kept the same toe in the boxes and twisted the fins the remaining 2.4 degree toe on the base. So we could use the pre twisted fins for older boards as well and now you could still put symmetrical fins in the boards and it would work OK, just more drag. Most of the time I put 2 degrees in the boxes, sometimes 1.9 or 2.1 if the board will be predominantly used in big or small waves. 2.3 degrees for example is a lot of fun in small waves but starts to become twitchy in bigger waves/higher speeds. So to stay on the safe side I stay withing the 1.9-2.1 degree range. With bigger side fins you can feel some difference but it still works in most conditions.Those red and black ones were the first pretwisted fins from 2010. They were made by a surfing fin company with RTM technique, this is fine for surfing fins but turned out to not really be strong enough for windsurfing. So I changed to G10 CNC milled fins. The RTM fins had a nice flex though. They had a 60-40 NACA 10 profile. Since 2015 I use Jowkowski profiles and instead of 60-40, I give them camber so even the wrong way around the fin work well for example when going up wind, just the maximum angle the fin can handle in hard turns is lower but in hard turns, the outer fin usually leaves the water. When the outer fin leaves the water, you feel a boost in the turn. Surfers usually call this drive. So I place the side fins fairly close to the rail to make maximum use of this effect.

If you mark the angle on the board with a bigger distance between front and back, the angle of the markline becomes more accurate. When I was still shaping by hand, I placed a mark at the back of the box and another 50cm in front. Then simply over grind the MT bases so you can turn them in the box and line them up to the mark line. Wax the box (and screw) well so you can fill any remaining void with resin. I use an injection needle to inject the resin to the bottom and the air can escape easily. Less of a mess as well.

sheddweller said..
Thankyou. So as I have 0.8 degrees of toe in the V board i need to add a further 1.5( 1.2+0.3) degree of toe at the fin base to give these twisted fins a fair chance. Correct?

Yes, for the base of the fin. The fin itself is turned 2.3 degrees on the base again. It will not be possible to do it to the tenth or even 0.3 of a degree by hand but try to be as accurate as you can, that will work well enough. With a caliper you can make fairly accurate marks on the base.

Bouke-Witchcraft said..

Yes, for the base of the fin. The fin itself is turned 2.3 degrees on the base again.

Does this also apply to the SR fins ? IMO the feel ok for less than 0,5 toe in the box but draggy in more toe.

How out of touch with reality, can windsurfers actually become?

What if your riding a symmetrical board , could you have toe in one side and toe out the other side ?

Basher said..
How out of touch with reality, can windsurfers actually become?

Here is a comparative chart:
Turn on, tune in, drop out

Bouke-Witchcraft said..

Your normal black fins fit very well 1 o to 1,5 o toe in boxes Your SR fins are very draggy IMO in more than O,5 o, and are best for parallel boxes. IMO They are very good fins but personally, I like the surf fins better. I use your fins sometimes for cut back side and it works great along with a slightly bigger and wider one with a lot of drive bottom turn fin. IMO fins could not be the same if you like (don't agree that all tires should be the same) esp in quads for ex you can go xs - s in one side and the opposite s - xs to the other side with great performance

My board came with 21 cm center and 11 cm sides and I wasn't happy with that setup. I've been playing around with small center and big sides (17 cm center and 14 cm sides) and I have tried both straight fins and 3 degrees asymmetric. Both types of sides work really well, I can't really tell which setup (asymmetric or straight) I'm riding just from the feel of the ride. For me the key to improving performance was switching to a smaller center and bigger sides.

Am pretty sure Jesus' daily driver had camel toe in

Brent in Qld said..
Most likely the answer to rail shape Vs toe in angle Vs vee Vs tail width Vs volume Vs concave Vs tail shape Vs thruster Vs quad Vs length of board behind fins Vs distance in from rail Vs cant Vs fin type, rake, foil, flex, material Vs rider weight (soaking wetsuit+harness and sunblock), skill, height AND BALL SIZE on any given day may well turn out to be subjective to the individual.

Gut feeling... the answer will only be revealed by devine revelation and only if the father, son and holy ghost have used the latest sails (GOD forbid Ben Severne alters mast curve on his Blade pro 5.0) in cross-on, side shore and cross-off during both float+ride and fully-sick conditions at your local at low tide.

Then again, the answer might just be 49.

It's 43.
For those who haven't seen , ( Movie 43 ) , watch it .
It is fantastic.
It will change your life in a good way.

Lost too many hats wavesailing. Set wave on the head, hat gone... Thus sunblock and therefore it must be included in the two decimal factoring of ground swell direction when deciding chord length of your foot strap covers.

FWIW
My new 2025 Goya Quad 104 has roughly measured about 5 mm toe in. The first Goya board with toe in of several that i've owned since 2014.

Imax1 said..

Brent in Qld said..
Most likely the answer to rail shape Vs toe in angle Vs vee Vs tail width Vs volume Vs concave Vs tail shape Vs thruster Vs quad Vs length of board behind fins Vs distance in from rail Vs cant Vs fin type, rake, foil, flex, material Vs rider weight (soaking wetsuit+harness and sunblock), skill, height AND BALL SIZE on any given day may well turn out to be subjective to the individual.

Gut feeling... the answer will only be revealed by devine revelation and only if the father, son and holy ghost have used the latest sails (GOD forbid Ben Severne alters mast curve on his Blade pro 5.0) in cross-on, side shore and cross-off during both float+ride and fully-sick conditions at your local at low tide.

Then again, the answer might just be 49.

I understand ball size , and shape , in lots of wind , but , sunblock ? Who uses enough sunblock to counteract toe in angles ? I suppose with enough sunblock you could be top heavy requiring larger side fins which will deliver more grip needed for sudden wayward , aft, movement . Lucky for me I use a hat instead of heavy sunblock. One less thing...

I heard the term toe in a couple of times recently, and decided to look up what it meant, found my way to this thread. I went right into windfoiling a couple years ago, with no prior windsurfing experience, so I haven't used a board with multiple fins, thus no knowledge of toe in. But now I'm concerned.
The tail wing on my foil has little vertical wingtips, but they don't seem to have toe in. Do they need toe in? how much? Based on the thread I assume it depends on fuselage length and possibly the amount of sun block I use?

Toe in is like sweet chilli sauce, the more the better. Same with sunblock, always more. Also never underestimate extra zinc on areas where bone is close to the surface for max bottom turn initiation. Think of zinc like the sour cream to the sweet chilli, always better.

As for your fancy vertical wingtips, I can only assume the reduction in whitewater being sucked forward by a traditional tip vortex is being limited by these fang dangled tip-bits. Best not to get into fuselage length with windsurfers though, we're a self conscious bunch.

I'm at the pub.

As a group can we accept that 1mm is not toed in because it's the outcome of manufacturing requirements to avoid toed out.