Moses Onda 633, The Fix !

[ldhr]

I had the same issue - the 633 changed the balance point to be way forward because of the large wing.
I move the mast board attachment all the way back and foot straps as far forward as possible (SS Alien Air).
Still too much forward foot pressure required to maintain proper trim.

I shimmed the mast to fuselage as shown in the Delta Foils video.
It did not change how wonderful the 633 wing rides.
The only difference was reduced foot pressure required to trim the board.
The 633 is amazing and the adjustment (shim) took 3 minutes.

[grigorib]

You buy a large wing with massive lift - and pressure on your front foot if fixed to a certain position - and then shim it in order to make it behave like a smaller one ..

it does sound funny, but the real point is keeping the extra lift and also keeping the mast where it is - it's kind of a hassle to move the mast if you switch between 590 and 633 wings.

[oregonkiter]

The shim under the mast does not make the wing behave differently, or ride "like a smaller wing." What it does is move the center of effort relative to your feet--that's it. Wing flies the same.

Today I decided I wanted to ride with my back foot 1 inch farther back to get more leverage for tight turns. I used a shim cut from a CC. On a 105 cm mast a single CC shim moved me back about 1-1.5". Perfect! Pretty amazing to me.

Really stoked about this simple, no cost adjustment

[Foxi]

shimming the foil to change AOA means kind of powering or depowering the foil, given a horizontal deck and fixed speed. Reducing the up forces in lowest speeds by depowering the foil / lowering AOA will come at the cost of later foiling/higher to foil speed.

[Peter_Frank]

shimming the foil to change AOA means kind of powering or depowering the foil, given a horizontal deck and fixed speed. Reducing the up forces in lowest speeds by depowering the foil / lowering AOA will come at the cost of later foiling/higher to foil speed.

No, it wont be on any cost, the relative AOA between wings are the same, so absolutely no difference in speed or performance.

The board angle though, will be changed, but this is a practical thing - and one could in fact shim the mast/fuselage to get mast tilted forward up towards the board (as this thread is all about), and then shim at the board connection too so the board has the same angle.

This would be the "right" way, if your board angle is good in advance - but do you know if it is ?

Some boards could take some shimming either up or down IMO and preference

A bit off topic maybe, but flat skimboards dont work well because you can never get the right angle for starting as well as riding - requires two very different angles

PF

[Foxi]

shimming the foil to change AOA means kind of powering or depowering the foil, given a horizontal deck and fixed speed. Reducing the up forces in lowest speeds by depowering the foil / lowering AOA will come at the cost of later foiling/higher to foil speed.

The board angle though, will be changed

Frank, that´s why I wrote "given a horizontal deck". If AOA is perfect/optimised as Moses constructed it, you will have to compensate the shimming by a non-horizontal deck. Or adjust the parallelogram @ mast/board connection. But I got you of course. I´m coming from a perfect word foilwise, you assume it isn´t anyway and shimming might be an optimisation. My basic assumption always is: everything comes at a price