My apologies for another question about aluminum fuselages. As you can see in the photo below, I am getting corrosion where the carbon masts fits into my fuselage. Is this common? I disassemble my fuse from my mast after each session and coat my bolts and washers with tef-gel. Of all the problems I have with my fuse, this is one that I worry about the most. The corrosion is happening at the thinnest part of the fuse (in the slot). I wouldn't be surprised to see a crack form at the hole.

If this kind of wear and corrosion is not common then I guess I just have a fuse with poor anodizing. On the other hand, if this isn't uncommon, I'm wondering why more companies don't use a carbon fuselage like AFS? This fuselage is 1.5 years old.

I'm juggling lots of different options in my head. If I could fit my Sabfoil mast into a different fuselage I would jump ship at this. In the mean time I think I will try to put some zinc sheet in this slot, although I'm not confident in the electrical contact. Perhaps I will first try to remove the anodizing at the bottom of the slot with some NaOH.

Not that it will help with your current fuselage, but you can check the anodize with an ohm meter if you have one. Should have infinite resistance if the anodic layer is present. I've seen some parts dyed black, but not anodized. Fortunately for me, I'm in fresh water, so never had those issues.

At least in my personal opinion I believe a lot of people look way too deep into this problem.

Anodizing is not the answer to stop the corrosion of the dissimilar metals in saltwater this is proven theory in the boat industry.

In the boating industry you use a two-part epoxy zinc primer. The amount of time of labor material cost and weight is just not worth it on this part.

Just focus on going riding and having fun.
Here's some pictures of what I use now I'm not even concerned I just keep on riding.





And as far as the anodes go a complete waste of time I find it kind of funny that they're installing zincs on this stuff now....

But each their own.

Cover all joints in grease prior to assembly, do it from new and you will not have a problem.

I Lanocote everywhere that carbon meets aluminum.

Yeah, I put tef-gel between the wing/stabilizer and fuse but I totally did not think to do it for the mast/fuse interface.

I have found with the Moses tapered Mast to the fuselage connection that if you put any grease on it it comes loose.
Where you have corrosion the fuselage does not touch that part of the mast there's a gap and it traps the water in there and causes the corrosion definitely cover that with grease if you're concerned but do not put it on the tapers.

If you're concerned you need to disassemble it and wash it with soap and water after every use that's the only way to slow it down but that won't even stop it if you're in brackish or saltwater.

At least for me I have a realistic outlook I have a 3-year window for my equipment before an upgrade my current foil is there but still going strong and ugly to the eye.

I leave it assembled in my van all summer long after riding and don't wash it and don't do anything other then tough gel and I don't have any problems with the fasteners.

I get over a hundred sessions in the summertime and now I spend the winters down south in baja that adds almost another hundred days.

I can say conservatively this kit in the picture 600 plus sessions well over a thousand hours of time riding.
I still have 100% total faith in this kit and I'm going to continue riding it this summer back up in San Francisco till I upgrade to the new 115.

A little corrosion gives it a little character I have better things to do than waste a bunch of time working backwards I'd rather be working forward so I can get buy a new one every 3-year which I'm already past I was just waiting for the new 115.

The Moses got a bad rap with this stuff and also with the tapered fuselage connection. For me I find if I install the fuselage to the Mast and tighten it and then strike it with a 2 lb dead below Hammer a couple times and re torque it it does not come loose after that no matter how many times I ride it.

I know the stuff is expensive but look past that it's all about the quality of your sessions if you're worrying about your equipment all the time you're not going to progress at the rate that you want to especially with a limited number of sessions. Ride it like you stole it.....

Moses Foils Rock..............

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Gwarn said..
I have found with the Moses tapered Mast to the fuselage connection that if you put any grease on it it comes loose.
Where you have corrosion the fuselage does not touch that part of the mast there's a gap and it traps the water in there and causes the corrosion definitely cover that with grease if you're concerned but do not put it on the tapers.

I can say conservatively this kit in the picture 600 plus sessions well over a thousand hours of time riding.
I still have 100% total faith in this kit and I'm going to continue riding it this summer back up in San Francisco till I upgrade to the new 115.

Thanks for the feedback. I carry a rubber mallet with me to remove the fuse from the mast, I don't mind giving it a wack. I'll coat the bottom of the slot and leave the tapers. If I can get 600 sessions out of my kit, I will be happy. This stuff can't be made to last forever, at least not an economical cost. I'm ok with that. I wasn't worrying about the corrosion until last fall, when I saw a steep acceleration in the growth and loss of material. As long as that slows down a little, I will be fine I think.

My AFS Wind95 foil from March 2019 looks almost brand new, yes I did replace some wing inserts that got pulled out 3 mm after a gust picked up the whole kit and threw it 30' down the beach, and I did have to add side shims on the stab. and wings to get them to be at 90 degrees to mast, but this foil is bomb proof and has only been in salt water year round. Carbon fuselages are more expensive to design and produce, that is why most companies use aluminum fuselages they are cheap and easy to make. Takes a team of true craftsmen to make an all carbon foil and wing set that last and last and last! It is still a great foil 4 years on, that performs outstanding in conditions from 9-30+ knots with a solid controllable flight, check out foilandco.com

Hey Gwarn, you are asking for trouble if you keep riding that fuse with that stress corrosion crack at the front of the tapered hole. Stress riser waiting to fail. Won't be long before you have a big ole fin under there.

When I mount my SAB fuse to the mast, I use a #12 split SS washer (maybe it's a #10, can't remember) on each bolt. Those compress better than do the paper thin flat washers that come with those bolts. They hold the bolts in place MUCH better. Even then I carry a 5mm hex key with me and re-tighten those bolts every 20 minutes on the water until they stay tight. It takes 3 or 4 cycles. After that they are tight for weeks. I do re-check them after every session to make sure. The split washers fit down into the holes no problem, and they STAY ON the bolt when you remove it (unlike the paper thin washers which fall off into the grass).

You could always tell a new SAB user because they wonder where the front bolt has gone after coming in from a foil session.

That 2-bolt tapered joint is a weak link in an otherwise excellent SAB design.

A proper taper setup should hold even tighter with Lanocote.
I used it exclusively with my Gong aluminum and you have to knock that apart with a mallet. I use it on my Phantasm now which doesn't appear to have a taper and instead relies on being bottomed (like a modern foil box). On both the Lanocote keeps everything tight.

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segler said..
Hey Gwarn, you are asking for trouble if you keep riding that fuse with that stress corrosion crack at the front of the tapered hole. Stress riser waiting to fail. Won't be long before you have a big ole fin under there.

When I mount my SAB fuse to the mast, I use a #12 split SS washer (maybe it's a #10, can't remember) on each bolt. Those compress better than do the paper thin flat washers that come with those bolts. They hold the bolts in place MUCH better. Even then I carry a 5mm hex key with me and re-tighten those bolts every 20 minutes on the water until they stay tight. It takes 3 or 4 cycles. After that they are tight for weeks. I do re-check them after every session to make sure. The split washers fit down into the holes no problem, and they STAY ON the bolt when you remove it (unlike the paper thin washers which fall off into the grass).

You could always tell a new SAB user because they wonder where the front bolt has gone after coming in from a foil session.

That 2-bolt tapered joint is a weak link in an otherwise excellent SAB design.

That is why AFS eliminated the fuse./mast joint!, all their foils have a one piece mast/fuselage T-bar. Sure, not as easy to fly on a plane (which I have not needed to do), and never have to deal with that joint.

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segler said..

When I mount my SAB fuse to the mast, I use a #12 split SS washer (maybe it's a #10, can't remember) on each bolt. Those compress better than do the paper thin flat washers that come with those bolts. They hold the bolts in place MUCH better. Even then I carry a 5mm hex key with me and re-tighten those bolts every 20 minutes on the water until they stay tight. It takes 3 or 4 cycles. After that they are tight for weeks. I do re-check them after every session to make sure. The split washers fit down into the holes no problem, and they STAY ON the bolt when you remove it (unlike the paper thin washers which fall off into the grass).

Wow, you tighten the bolts more in one session then I have in the last 100 sessions. Phantasm+tefgel+Ttape+torque wrench makes life easy.

After those first 3 or 4 tightenings it stays tight for the rest of the summer. I re-check for security. What loosens the front bolt is the 250 pounds of lift exercised by the front wing. Re-tightening 3 or times is more effective than any amount of rubber malleting.

You'd be amazed at how many SABfoilers lose the front bolt. The Columbia River is accumulating a good collection of them. Sailworks now throws in spare bolts when you buy SABfoil gear.

And, yes, stop using those paper thin flat washers unless you have a set of a hundred of them. Rigging grass in various parks are accumulating a huge collection of them, too. Switch to the split washers that stay on.

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segler said..
After those first 3 or 4 tightenings it stays tight for the rest of the summer. I re-check for security. What loosens the front bolt is the 250 pounds of lift exercised by the front wing. Re-tightening 3 or times is more effective than any amount of rubber malleting.

You'd be amazed at how many SABfoilers lose the front bolt. The Columbia River is accumulating a good collection of them. Sailworks now throws in spare bolts when you buy SABfoil gear.

And, yes, stop using those paper thin flat washers unless you have a set of a hundred of them. Rigging grass in various parks are accumulating a huge collection of them, too. Switch to the split washers that stay on.

I use a hard plastic/rubber faucet washer under the metal washers, hard rubber washer has a friction fit on screw and adds some shock absorption too.

We are talking about the joint between the mast and fuselage (the SAB uses 2 bolts to hold the bottom of the mast in the tapered slot on the fuselage), not the top of the mast and the board.

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segler said..
We are talking about the joint between the mast and fuselage (the SAB uses 2 bolts to hold the bottom of the mast in the tapered slot on the fuselage), not the top of the mast and the board.

Oh man, that is way more serious, glad I have a one piece mast and fuselage!

My AFS-2 is also one piece mast and fuselage. Fine for structure, but a real hassle for shipping. I took mine with me to Florida, where it will now stay. It required a big box that the airline griped about.

Pretty much everybody else in the world do separate mast and fuselage, joined with screws or bolts, some sideways (SB), some axial (SAB, SS). LP is unique in that the carbon fuse fits into a tunnel at the bottom of the mast.