Now that the axis ultra mast is out, it looks a bit like the cedrus evo, does that mean this new weird mast shape is going to be the next new thing?
No comments? We’ll kick it off. We have felt for years that from an engineering standpoint, a tapered mast is not optimal. The long chord length up high doesn’t help with ventilation or give you appreciable stiffness but does increase drag significantly for water starts or when the mast is ridden at variable heights. The low chord length down low promotes ventilation and reduces torsional stiffness where it is needed most. We designed Evolution Wind to give riders ventilation resistance and torsional stiffness where it’s critical (where the mast pierces the water) and less wetted area where it’s not (up high and down low). Feedback to date confirms the engineering: it’s been impossible to ventilate and it’s stiff and fast even as you vary your ride height. While the Axis mast may look similar, it’s really a traditional tapered mast with more a discrete transition point.
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I’m not arguing, but genuinly asking, doesn’t the Evolution Surf have a long chord length up high, tapering to a low chord length down low? Or are you just talking about the masts when used for Winging. Thanks 
The new mast is fast, fast… and stiff…and too expensive. But, the gain is there. Hope they will be able to produce it at a cheaper price in the future
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How come other uhm masts are cheaper. Ie afs silk uhm is cheaper than axis hm.
Sorry, we should have given more insight into the principles of Evolution Surf as they relate to Wind. Yes, the design theory behind Evolution Wind is applicable to longer masts ridden at greater speeds and/or more aggressive angles of attack relative to the wind. These masts inherently feel more flexible due to their length, and are more prone to ventilation. The layup and geometry for Wind has been optimized for torsional stiffness in the longer lengths, which was something previous clients asked for. We have many riders who have both a 70cm Cedrus for prone and a 90cm+ for wing or kite, and the longer mast just didn’t feel as stiff in some cases. Evolution Wind is a totally different layup and profile available in lengths 80cm+ where the additional material is needed to compensate for added length. It has been ridden back to back with the new Axis UHM mast, using the same foils and board for an apples:apples comparison, and confirmed to feel just as stiff and fast. One difference noted was that it did feel more locked in at speed than the new Axis, which is honestly something we want. Dropping into big swell, or riding close-hauled, we wanted stability, and got it through additional chord length at the piercing zone of the mast.
Evolution Surf actually has the same chord length as Wind up high and down low, but instead of growing longer in the middle, it decreases to reduce wetted area (drag) and improve glide. This is closer to a more traditional tapered mast, yes. In theory it does come at the expense of ventilation resistance, but ventilation is much less likely to occur when prone foiling due to lower speeds and less aggressive angles of attack relative to wind chop. Prone masts are also shorter, so they don’t need as stiff of a layup or as big of a section profile. None of our testers have experienced ventilation with Evolution Surf, and based on GPS and ride times it’s proving to be just as fast as any “thin” OEM mast. We’re confident it works well for winging and other forms of foiling up to 85cm-it’s stiffer and stronger than our original Classic which is still an industry benchmark. Many of our launch customers are going with longer Surf models for winging swell on bigger/surfier foils. But beyond 85cm, we force riders into the Wind model to ensure that stiffness is not compromised and ventilation resistance is high for aggressive upwind riding.
We have written extensively about the use of high modulus fiber in foil masts. Ultra High Modulus (UHM) fibers can span a range of stiffness and prices with the extreme end being twice as stiff and expensive as lower end UHM. You can see the range of variation in stiffness between standard, intermediate, and high modulus in the chart linked previously. The reality is with carbon masts, the majority of the cost is the labor, not the material. But when you are making a solid carbon mast, with 60+ plies, the material costs do add up. This could explain the difference between AFS and Axis, or it could simply be the grade of material used.
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Ah sweet, thanks for getting back to me. It’s a pretty amazing time in this sport, where new ideas, designs and materials are still being discovered; I think we’re all pretty lucky to be involved at this time in its history
The new mast is pretty nuts, it felt like a rocket was attached to the foil
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Can you tell us more? I’m pretty intrigued.
Did you join just to tell us this?
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No, I’ve been here for a while, Sjaak. But is there a problem?
sorry I meant to reply to 1000islandsfoil
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Ah, no problem, but let 1000islandsfoil be frothy, it’s all good. The only issue for me is I want more details
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