Cedrus Aluminum Mast

[headmount]

hello all, Kyle with Project Cedrus here. I value forums and would rather spend my time clarifying confusion or answering questions, than my money on marketing or google ads.

Regarding sealing the mast: I tried closed-cell spray foams and they did not last. I have also seen through experience that most aluminum masts will lose there seal, suffer from water ingress, and even worse, the water won't come out! So I made the decision not to seal the aluminum mast, unless I had a year+ to do proper R&D on a seal that lasts, and let clients address water ingress if it is important to them. Also keep in mind, adding $20 in labor/materials to seal would add 40+ to the final price. That's just unfortunately how it works when you get involved in retail. Finally, I couldn't open myself up to warranty issues by promising a sealed mast. I'm just being transparent. Most brands have reasonably high warranty rates, and thanks to a low cost, can afford to replace a bent aluminum mast or two. I can't afford to replace masts, aluminum or carbon, and fortunately I don't have to. I can tell you for certain that it actually costs more to install my stainless helicoils in the aluminum mast, than it would to buy a complete extrusion from China. But I believe in supporting our community with meaningful manufacturing jobs.

As for stiffness, it is not in the eye of the beholder. It is 100% scientific, engineering, objective data. I have tried to explain the proper way to characterize stiffness of a mast, but Adrian at Axis will not listen. And I only use his name because he is open in his latest Blue Planet interview about his feelings of Project Cedrus. Hanging a weight at the end of the mast is not a proper test for mast stiffness. It is a good way to assess the strength/stiffness OF THE MOUNT. The mast is subject to a constant bending moment when being ridden, which if you are not an engineer, you may not understand. Here is just one link if you want to dabble in structural engineering: https://www.constructupdate.com/what-is-shear-force-and-bending-moment-diagram/ The cantilever test that Axis does puts a maximum moment at the mount, with a decreasing moment throughout the length of the mast. It will give you inaccurate direction regarding the actual stiffness of the mast. It's also the main reason so many brands taper masts, because they don't think it impacts stiffness. But it does. Properly testing is not complicated and does not require fancy equipment. I showed Devon at Wake Thief how to properly test bending stiffness of a mast here: https://www.youtube.com/watch?v=auJ2WlxNMfA We didn't address torsion at this time, but in other videos, he has.

I can see how this would easily result in confusion and differing opinions on stiffness. If Axis is using a different test method, they will have different results. Anyone who's ridden a NoLimitz mast has told me it's not as stiff as Cedrus. Is it thinner? yes. Is it lighter? yes. But it is not stiffer or stronger, partly because they too test incorrectly, as evidenced by their own website. I started this project in large part because I was fed up with the marketing in sports equipment, when brands make false claims, especially related to Cedrus, it boils my blood. I am setting up a proper testing procedure and plan to be a guest on Blue Planet to continue showing the world how to design and build a stiff mast as I have on my blog since 2018...

Thank you, Kyle @ Project Cedrus with lots of skin in the game

Excuse me Kyle but I watched Devon's video a few times looking for a conclusion from him that his aluminum mast was not as stiff as yours and that there was a performance disparity.  But I failed to find it.  Did I miss something?  Devon's conclusion seemed to say he could tell no difference in performance.  Did Devon's test qualify in the way you would do it?  I do like the soft LE & TE.  He did too.

[surfcowboy]

HM, he's talking about the test method. When that video was done the Cedrus aluminum wasn't out yet.

[Dwight (DW)]

I have tested masts with prototype front wings so massive, they never went to production. Tested with 19mm thick aluminum masts versus the stiffest possible tapered carbon mast prototypes.

These massive front wings truly expose the difference in rider feel between a mast flexing lower versus higher.

So rider feel is number one to me, after testing at the extremes.

[BayAreaKite]

Thanks @SUS4Life. Asking for a standard test is a lot. I'm just asking for basic proper engineering, and no false marketing. It's not just the foil world. I'm sure many of us are mountain bikers, skiers, etc. How many people do you see walk into a ski shop and pull a ski off the rack and flex it between their hands and feet Another very subjective test. I did notice when I upgraded my MTB to carbon, I immediately felt the stiffness difference. And it was the exact same model bike, just different frame materials. A bit more complicated to measure stiffness in MTB frames, especially full suspension, but it's just as important.

@headmount that video was shared to show a more representative testing loadcase for a mast. Pushing on the wingtips will induce a constant bending moment in the mast, and allow you to compare the true bending stiffness of the masts. Assuming the wings and mast length are the same of course. When you really get on the rail of your board and drive hard upwind, or roll your foil wings, this is the type of loading you are putting in the mast. Hanging a weight on the end and measuring deflection/strength is really good if you want to see how strong your mast/mount is when someone lands a trick improperly. It's a good "abuse load" test. That's about it.

[clay]

Affordable interchangeable durable masts, wonderful and very good for foilers to have this option.

So are the adapters connected to the mast by butt joint?  Or is there some male/female connection going on in addition to the bolts?  How deep are the threads?  Love to hear Kyle's design thoughts on this.

One of the things I love about the Axis doodad and the F-one titan foot is that a loose bolt isn't a big deal, and bolts never come loose.  With the slingshot aluminum mast to fuse a bolt would occasionally come loose and be a session ender.

[jondrums]

Clay, in my experience the Cedrus mast, adapter and connection system is very reliable (I've been using the carbon mast, not the aluminum, but I think its the same).  I credit that to the use of M8 fasteners instead of M6 used on a number of other systems.  The Axis system has been rock solid too (M8).

[burchas]

Been using the Cedrus carbon for a while. Axis, GoFoil, SlingShot, F-One.
No issues with any of the systems. TefGel from the get go.

[Vancouver_foiler]

Depending who you're talking to. The stiffness is the same as AXIS 19mm aluminum, or greater than the AXIS 19mm aluminum. Also depending who you're talking to the cedrus carbon is stiffer than the AXIS power carbon high modulus and the bend tests AXIS has done are bad tests and don't actually reflect stiffness in the real world.

So stiffness is in the eye of the beholder I guess.

I have no skin in the game as I don't ride AXIS or own a cedrus at the moment.

Joe-Stiffness is most certainly not in the eye of the beholder lol. It's a scientific measurement.
Depending on where and how it is measured give better real world values(torque, medial, lateral Forces, etc)
Having been a long time Axis guy, the carbon mast is very close to the same stiffness, but has a much more lively spring after its been torqued.

[Vancouver_foiler]

hello all, Kyle with Project Cedrus here. I value forums and would rather spend my time clarifying confusion or answering questions, than my money on marketing or google ads.

Regarding sealing the mast: I tried closed-cell spray foams and they did not last. I have also seen through experience that most aluminum masts will lose there seal, suffer from water ingress, and even worse, the water won't come out! So I made the decision not to seal the aluminum mast, unless I had a year+ to do proper R&D on a seal that lasts, and let clients address water ingress if it is important to them. Also keep in mind, adding $20 in labor/materials to seal would add 40+ to the final price. That's just unfortunately how it works when you get involved in retail. Finally, I couldn't open myself up to warranty issues by promising a sealed mast. I'm just being transparent. Most brands have reasonably high warranty rates, and thanks to a low cost, can afford to replace a bent aluminum mast or two. I can't afford to replace masts, aluminum or carbon, and fortunately I don't have to. I can tell you for certain that it actually costs more to install my stainless helicoils in the aluminum mast, than it would to buy a complete extrusion from China. But I believe in supporting our community with meaningful manufacturing jobs.

As for stiffness, it is not in the eye of the beholder. It is 100% scientific, engineering, objective data. I have tried to explain the proper way to characterize stiffness of a mast, but Adrian at Axis will not listen. And I only use his name because he is open in his latest Blue Planet interview about his feelings of Project Cedrus. Hanging a weight at the end of the mast is not a proper test for mast stiffness. It is a good way to assess the strength/stiffness OF THE MOUNT. The mast is subject to a constant bending moment when being ridden, which if you are not an engineer, you may not understand. Here is just one link if you want to dabble in structural engineering: https://www.constructupdate.com/what-is-shear-force-and-bending-moment-diagram/ The cantilever test that Axis does puts a maximum moment at the mount, with a decreasing moment throughout the length of the mast. It will give you inaccurate direction regarding the actual stiffness of the mast. It's also the main reason so many brands taper masts, because they don't think it impacts stiffness. But it does. Properly testing is not complicated and does not require fancy equipment. I showed Devon at Wake Thief how to properly test bending stiffness of a mast here: https://www.youtube.com/watch?v=auJ2WlxNMfA We didn't address torsion at this time, but in other videos, he has.

I can see how this would easily result in confusion and differing opinions on stiffness. If Axis is using a different test method, they will have different results. Anyone who's ridden a NoLimitz mast has told me it's not as stiff as Cedrus. Is it thinner? yes. Is it lighter? yes. But it is not stiffer or stronger, partly because they too test incorrectly, as evidenced by their own website. I started this project in large part because I was fed up with the marketing in sports equipment, when brands make false claims, especially related to Cedrus, it boils my blood. I am setting up a proper testing procedure and plan to be a guest on Blue Planet to continue showing the world how to design and build a stiff mast as I have on my blog since 2018...

Thank you, Kyle @ Project Cedrus with lots of skin in the game

Good explanation Kyle-I just made  similar comments.

Regarding the open mast-You need to get some replacement rubber inserts made my friend. If you don't it will severely limit your market. Quire frankly, most the new foilers getting into it are clueless.
E3

[Hdip]

Yeah. Maybe bad choice of words. More important to some than others, that might  be a better choice. I don’t exactly like mast flex. But I rode a Takuma aluminum mast just fine.

But I was referring more to AXIS claiming one thing and Kyle claiming another which has been clarified since my post.

]

Joe-Stiffness is most certainly not in the eye of the beholder lol. It's a scientific measurement.
Depending on where and how it is measured give better real world values(torque, medial, lateral Forces, etc)
Having been a long time Axis guy, the carbon mast is very close to the same stiffness, but has a much more lively spring after its been torqued.

[headmount]

I have tested masts with prototype front wings so massive, they never went to production. Tested with 19mm thick aluminum masts versus the stiffest possible tapered carbon mast prototypes.

These massive front wings truly expose the difference in rider feel between a mast flexing lower versus higher.

So rider feel is number one to me, after testing at the extremes.

Could you tell us the result of your tests? Axis has a new 1310 with a 51" span.  The 'Wake Thief' was saying, 'for the 1310, the tip deflection in roll direction (bending of mast) was about 20% less for high mod carbon vs aluminum, and tip deflection in yaw direction (torsion of mast) was about 30% less for aluminum vs high mod carbon.'  I assume he's referring to the Axis 19m aluminum.   Is the Cedrus alum better than the Axis 19mm alum in (roll) tip deflection?  Sounds like King Solomon's choice.  Deflection or yaw, which is more important?

[Thatspec]

My takeaway from the Wake Thief video was that the new HM Axis carbon was actually a little stiffer in roll (deflection) than the 19mm aluminum. It was yaw where the aluminum was stiffer. 'Seems' like more stiffness in yaw would be less important than roll but that's just guessing.

I'm just not buying any more foiling gear without demoing first (yeah, even I don't believe me

[PonoBill]

I suspect beginner/intermediate foilers would feel and dislike yaw before they would roll deflection. The old Axis carbon mast is kind of a good case in point. With even Axis 1000 or 900 wings I could feel a delay between steering rotation and the foil responding. For bigger wings like the reminiscent of a car with loose steering. That's why my old carbon masts don't get used and I ride 19MM aluminum. I have a Cedrus Clydesdale version but I haven't tested it yet. I need to make an adapter for it, I don't like the attachment method of the standard Cedrus adapter.  I'm still not sure what roll deflection would feel like. Given the long wings I prefer I probably have plenty but I'm too numb to feel it.

[jondrums]

I personally don't think yaw stiffness matters much.  There is nothing on the foil down there that resists yawing, so there isn't much way to even apply a high yaw torque on the mast.  If there was a vertical stabilizer in the system it might matter more.  The yaw stiffness just needs to be high enough for the first mode resonance so it doesn't feel wobbly.  For my money, I want roll stiffness

[StellaBlu]

We focus a lot on mast stiffness, but not necessarily on foil wing stiffness.  Why is that?  Wouldn't a flexy foil wing have just as much (possibly more) of an impact on the system as the mast?  I'd guess that my Takuma wing flexes more than my Cedrus mast.

Am I wrong?  Does it matter?