How Rocker & Rake Improve Foiling

I believe as foils get faster, we need more rake. For example, professional windsurf racers use 3.5 degrees rake and they go 35-40 knots.

[@joebenjamin6139]

As always great information Dwight. Thanks for sharing. I have to do some measuring now to see where my kit is set up.

[@blooskyy7]

Amazing advice, I had been thinking about this recently and your explanation was perfect timing. I'm definitely going to give this a try with my HA setup.

[@blooskyy7]

Gave this a try today on a HA foil and it worked liked a dream, the board gets on plane much quicker with less drag from the foil and lift off is way easier and smoother. Thanks a stack for sharing this great advice. Interesting discovery was I had to move the mast back slightly to rebalance foot pressure.

[@martinomovies]

Thanks for the explanation

[@youdigsurf]

I’m tying myself in knots since i have been using a different brand board to the brand of my foil, if you dont want any trouble just buy the same brand board 😅 It’s started with a armstrong foil on a gong board i couldnt tune properly ended with 2 degree shim and a stab shim , i changed for something more plug and play but having a rake shim is never the same than having the brand designer board. On my fanatic sky free te 2023 im using a front rake shim of 1 degree on my foil which us full forward on the us box, another issue with shimming is strap insert, that why i had to put the foil full forward in the box, because even if i had the strap full back i had a lever forward that was putting the nose down i was past the balance point. Here some tip to notice your board is not fine tuned , backleg burning, stay up straight on the board while flying and if the board cannot maintain the fly without you changing your balance it’s not balanced, same goes for changing foot in fly if the board fell off instantly you are not balanced either. The truth is , probably around 80% of people riding mixed gear doesnt have they board properly tuned ! As for the surf foil , i find easier to maintain fly with little bit of front foot especialy when pumping, backfoot is ok when the wave push you but when it’s stop 😟 it’s sux it more tiring to offcentered in the back and you feeling more the lift of the foil with little bit of front foot only issue, is you will loose little bit of bottom range , that why it’s better to alway favor the same brand , since then i purchased the same brand board for my foil in surf foil and it’s night and day…

[@laurence8988]

Cheers Dwight, I've been playing with this for sometime but couldn't explain it technicals as well as you have so thank you. I do have a question or two if you may have some thoughts to share. I use sunova boards, Armstrong MA foils but a project cedrus mast and fuse (no rake built into these) . What I spent awhile doing was to stand balanced on the board stationary and to get on foil without readjusting my feet. This ended up requiring a 1½° base plate shim. And the result is smooth effortless take offs 👍 The only thing about this setup is at speed sometimes my rear tail will suck up to the surface and pull the board almost windward and into a crash. I've just started to experiment with a mast fuse 1½° shim as this gives the plane the same desired effect. I have only had one go in light conditions to test a couple days ago. It seems to have a similar effect but need more trials. (80cm mast). Do you have any thoughts on the positives, negatives or changes i should of could make? Cheers if you do have an thoughts

[@foilsurfmachines]

Adding rake via the fuse, is same effect as adding via base plate shim. I think I read Armstrong added their 1 degree of rake via the fuse mount, not the base angle on the new mast. My guess is the boxy tail of that board is causing it. A board with the chine tapering more at the tail might give the clearance you need.

[@Wingerland]

Thanks Dwight for your good info. Did I see an R front foil. I have been wondering if Rs for low wind foiling without swell would be better to use due to improved glide and speed.

[@foilsurfmachines]

The R does make gliding through jibes and tacks in no wind very easy. I have the 960R. I’m currently learning when to use it versus the 980S.

[@Wingerland]

@@foilsurfmachinesthank you! I am considering to go strait to an R series for my low wind option. 145 pounds. 615s above 15mph, 770R below 15mph.

[@scottseale]

Nice timing! Experimenting with this at the moment on an Fone Rocket V2 (2022) and winging with Sabfoil Blades (w1000, w740), also w835 Onda. Quite a strong forward tilt at speed,making it feel quite strange and hard to get out of any touchdowns. Also hard to be efficient hiking upwind with the rail heeled over if the nose wants to be angled down. A 1 degree mast shim improves this a lot by giving 3.6deg rake and will be trying a 2 degree, which gives me about 4.6deg rake. I wouldn’t want to go much more than 2deg shim as the bolt threads now will be stressed a bit mote off axis and also the contact point of the mast securing bolts and washers will tend to take take an angle relative to the carbon mast base, instead of a flush seating. Thanks for the video.

[@foilsurfmachines]

I think Armstrong had the right idea when they updated their newest mast to include a 1 degree built in rake.

[@snowpigpow]

Wizard hat hardware fixes the angles problem of shim

[@foilsurfmachines]

@@snowpigpow I’d love to see Wizard Hat offer shims in smaller increments. My wife's board was dialed with 0.75 shim. Mine a 1.0 shim.

[@brianmckenzie1318]

Thanks for the design lecture, makes a lot of sense!

[@OCEANBOUND1]

nice explanation Dwight! I'm a little confused how with a leveled setup your nose will point down at higher speeds. does the foil and fuse typically ride that far off the level when at speed?

[@foilsurfmachines]

The thinner, faster foils, do seem to ride at very low angles. The Code foils are crazy thin. Mike’s Lab thin. 11.5, 12, and 13mm thick. It’s fascinating that windsurfers doing 40 knots need 3.5 degrees rake. Keep in mind your Armstrong mast has a built in rake of 1 degree. When added to your Armstrong board, I’d guess your rake is about 2 degrees also.

[@OCEANBOUND1]

@@foilsurfmachines I've been reverse shimming the mast cause of that 1 degree rake. I've been trying to paddle up on the flat and I feel drag, which seems to get better when I shim the back of the mast with a 1 degree plate. my technique has been evolving, so maybe I can get rid of that now. I guess different foils add another piece of complexity to the puzzle.

[@foilsurfmachines]

@@OCEANBOUND1 that makes total sense to me, because when I foil drive, I use 1 degree of rake. I’ll bet you’re at 1 degree rake when reverse shimmed. That 1 degree coming from the board rocker. Maybe this is why Code doesn’t build in rake to the mast.

[@foilsurfmachines]

@@OCEANBOUND1 I think when we SUP we lean forward as we paddle, getting the board pretty level. When we wing, we lean back against the wing pumping action. It would be impossible to learn forward and pump the wing. I tested 0.25, 0.5, 0.75. 1.0, 1.25, 1.5 shims winging to learn how they affect take off. Take off improved with more shimming, then when it got extreme, the board started to plow nose high and take offs got harder. It was a fun test.

[@scottseale]

Another scenario is a light rider on a relatively large foil pushing for high speed. The lift produced exceeds the bodyweight and so the rider has to compensate by trimming the large foil into a negative angle of attack which on a flat rocker board will ride nose down.