I got my first foil setup which includes a Katana mast from Unifoil. On the mast there is a sticker which implies that the mast is sharp, and that one might consider sanding it down. I’ve posted a pic below of this. There are a few places I’ve read people talk about sanding down the tips of the front wings of their foils for safety, but not the mast.
Is this something that would be good to do given that I’m a beginner and it’s likely I’ll bump this thing in the water?
You have to work really hard to touch the back of the mast. I almost never come into contact with it. As a beginner you’ll kick the stab for sure though and cut your feet. If you are nervous and have to sand it mark off and don’t touch/sand the bottom 6 in of the mast. That’s the most important part for efficiency and ventilation.
Safety tips - use a leash in the beginning - if you feel it pulling your safe , no pull cover your head and face.
Anytime I go down and I’m not 100% in control of the board I have one arm wrapped around my face, hand on the back of my head.
Practice keeping you feet glued to the pad when you go down - I’ll be upside down and backwards in the whitewater but my feet are still controlling the board
Thanks for the run down. If it’s pretty rare to come in contact with it I’ll probably leave it then. I have muscle memory from surfing to cover my/head face when I fall.
As far as other safety stuff is concerned, I am planning on using a leash in the beginning and I also have a helmet.
Just remember that you have to clear the board by two feet on every fall. Once you’re used to that you’re pretty safe.
Don’t correct, eject. Trying to save a fall is what gets surfers in trouble when they’re learning. Keep your entire body in line with the mast. Don’t lean out over the rail.
I sanded my trailing edge. I just took a block of wood wrapped in 120 grit sandpaper and ran it the full length of the mast one pass at a time until it didn’t feel deadly. I have not experienced any ventilation or unexplained dropouts while proning, winging or downwinding.
Peace of mind is worth the half % of efficiency that I may have lost.
Cedrus is not soft at all. Maybe if you smash through the outer coating and do enough damage to reach the rubber but any non catastrophic impacts are going to be the same as other masts. However, it’s VERY dull on the front and back so you won’t be cutting yourself with it.
When you’re riding your mast should not be getting heated by the sun. Not once this summer has that mast ever felt soft and capable of being pushed in with my finger. Claiming it’s soft and won’t hurt people is something I would never be able to back up.
Evolution Cedrus is “soft” relatively speaking. 95A shore hardness to be exact, at room temp. Much softer than carbon fiber or aluminum, and we’ve definitely had clients claim the rubber edges saved them when crashing into the mast.
Blunt trailing edges (sanded) have no performance impact whatsoever. Definitely no contribution to ventilation either, which initiates at the leading edge and where the mast pierces the water.
If there is no performance loss why do manufactures (besides yourself) insist on making them so sharp? Is it one of those things that is “perfect” on paper—but realistically there isn’t a measurable performance difference when riding?
To expand and clarify on that: 95A is like the wheels on a shopping cart which are quite hard. Since that’s at room temp, throw those into cold water and it sounds like it gets harder. So, getting hit by an Evolution mast is not a good idea.
Not all masts come super sharp. There’s a balance. If you ever ride a mast that is too blunt you can tell, it’s terrible. All of my foils record top speeds when I first get them and they are factory sharp. I always knock the edge off though and they all slow down just a touch after I do that.
I would much rather get stabbed by a butter knife made of rubber with a hardness of 95A vs. one of carbon fiber or aluminum. Shore A scale covers the 1-10MPa range for Young’s Modulus, and to put that into perspective, aluminum is 70GPa… at least 7,000X stiffer. I didn’t say it was a good idea, I said one was better than the other. Also not everyone is foiling cold water.
I also can’t speak to other brands, or know which ones insist on sharp trailing edges. But our work with experts who have designed foils since before the type of foiling we’re talking about here was even a thing, have shown us data and analysis that suggests super sharp edges have no performance benefit in the reynolds numbers we are talking about. Alternatively, the sharp edge is more prone to damage, causing injury, making noise, and harder to manufacture.
Wow that’s crazy JohnVu. Mine is rock solid. I just checked it and it doesn’t move at all! Checked with a buddies and his is solid too. Guess they are all a little different!
It could be I have the pre released versions (both are like that). Kyle could clarify.
Mind you when water is 2-15C it’s hard.
But even then it’s not hard enough to cut.
And I’ve cut myself with the Gong ultra sharp foils.
Levitaz (not slow!) use the Donaldson angle on their foils, those are not sharp (still sharper than Cedrus mast
