OK so I've finally got my hands on a foil (yet to get it wet) but am thinking it is best if I can do some maintenance before I start to use to prevent further degradation.

I know I have some aluminium cleaner I left any my father in laws place in Vic but that is not an option and I've no idea where to source such a thing.
I'm thinking a sand back then some kind of chemical prep before some paint. Ideally a sandblast and an epoxy paint but I'll have to compromise on this.

I've just bought be some tefgel, and I was thinking that the exposed carbon on the wing needs a little paint too.

The threads actually look OK after the first thread so I'm not stressed about them failing. Looks like bolts were used with tefgel, Just not rinsed in fresh and disassembled regularly.
Thoughts or suggestions?

Tefgel and other marine lubes work well when parts are clean, but get gummy-tacky-downright sticky with repeated applications. Gotta clean every 5 apps.

Looks like intergranular corrosion, this is terminal. I'm an aircraft structures repairer, repair of this type of corrosion is by replacement. intergranular as the name infers progresses through the grains of the alloy, destroying the structure and strength. As you grind away the corrosion it just keeps going deeper, looks like it is coming out the sides already.
Keep using it but watch for the wing getting loose as the structure is destroyed

Select to expand quote

airsail said..
Looks like intergranular corrosion, this is terminal. I'm an aircraft structures repairer, repair of this type of corrosion is by replacement. intergranular as the name infers progresses through the grains of the alloy, destroying the structure and strength. As you grind away the corrosion it just keeps going deeper, looks like it is coming out the sides already.
Keep using it but watch for the wing getting loose as the structure is destroyed

Nah the corrosion on the sides is from sitting inside the recess of the front wing.
I'm calling surface pitting not intergranular. I havent cleaned it off at all. I'll give it a rub with some scotch brite and water tonight and see what we get.

Aluminum and carbon don't mix. The carbon corrodes the aluminum. Carbon does not corrode stainless steel and titanium.

This is why the Boeing 787 has zero aluminum in the carbon structure. All metal is titanium.

If you have to mate carbon with aluminum, such as wing to fuse, disassemble often and lubricate with some kind grease or tefgel.

That looks pretty bad, and just because you can see "threads" does not mean they are not weakened/corroded. If you foil somewhere where you can paddle back to shore easily then maybe use it, but if the wing rips out the screws it could damage the bottom of the board. I would really look at replacing the fuselage. Looks like electrolosis occured between the steel screws and the aluminum. The mast screw inserts look fine, maybe they were disassembling the mast from the fuselage, but not the wing from the fuselage. What does the stabilizer screw inserts look like?

You could treat it with an anticorrosion solution like STABIL corrosion inhibitor, but still recomend replaceing the fuselage.

Big reason I got the AFS Wind95 foil, all carbon, and I am in salt water all the time, no corrosion between SS screws and SS inserts and I do not disassemble it reguarly, just rinse. But I did wrap the wing screw threads with teflon tape just to be on the safe side, and use lithium grease on the mast head and stab screw threads.

The two important questions are what directions the forces go, and how many "good" threads remain. On my Slingshot gear, there is quite a bit of corrosion, but the only part that has failed (repeatedly) is the little cap where the screws mounting the front wing go in. That has beefy (M8) screws but they go in only a few mm. It's easy to over-torque even with new parts. Eventually, the top threads just come out. I probably have replaced this part about 4 or 5 times in about 200 sessions (using tefgel, disassembling this part once every couple of weeks or so).
But even if one of the two screws was completely loose after a session, there never seemed to be any danger of loosing the front wing.

Your setup has 3 screws. I'd worry about this only if you get just a few turns on the screws, or if the wing is mounted on top, so that the wing's upward lift could theoretically push it off the fuse.

I drilles and tapped my Slingshot top plate all the way through and used longer bolts, I'd do the same with this and consider helicoils.

Marine grease or TeflaGel is one answer. Another is Dielectric Grease. I started using it on a trailer tonque. After 11 years it was still loose and it doesn't wash out with water/salt spray from the road. I use it on my Slingshot foil. After a year(fresh water use) it came apart like the day I put it together.

Select to expand quote

lakeeffect said..
Marine grease or TeflaGel is one answer. Another is Dielectric Grease. I started using it on a trailer tonque. After 11 years it was still loose and it doesn't wash out with water/salt spray from the road. I use it on my Slingshot foil. After a year(fresh water use) it came apart like the day I put it together.

But I think dielectric grease is designed to allow electricity to pass through it, may help galvanic corrosion occur in saltwater between dissimilair metals.

If you take it apart after a few uses - give it a good wash I use hot water and detergent - I then use a tefgel after drying and reassemble

is it okay to reassemble and store ready for next use or will corrosion atill take place due to the different materials ?

I like it assembked ready to go for after work sails where time is short

If you take it apart after a few uses - give it a good wash I use hot water and detergent - I then use a tefgel after drying and reassemble

is it okay to reassemble and store ready for next use or will corrosion atill take place due to the different materials ?

I like it assembked ready to go for after work sails where time is short

Select to expand quote

normster said..
If you take it apart after a few uses - give it a good wash I use hot water and detergent - I then use a tefgel after drying and reassemble

is it okay to reassemble and store ready for next use or will corrosion atill take place due to the different materials ?

I like it assembked ready to go for after work sails where time is short

I think you need salt water for the corrosion to occur. So if all the salt water is gone and everthing is dry and coated with tefgel you should be good to go after work, but I would take pictures now and then after a couple of months and see.

Anyone ever used this. I was thinking of getting some. Obviously still use tefgel or grease on threads but it should get into wing and mast to fuse connections to neutralise the salt.

Select to expand quote

Swindy said..
Anyone ever used this. I was thinking of getting some. Obviously still use tefgel or grease on threads but it should get into wing and mast to fuse connections to neutralise the salt.

Could just soak mast and fuse in water O/N.

Washing your streamline extension in fresh water after every use obviously didn't work did it.

Select to expand quote

Swindy said..
Washing your streamline extension in fresh water after every use obviously didn't work did it.

can not stop corrosion while using it!, it can be wet with saltwater for 5-8 hrs before I wash it, but I noticed after washing it the scews still hold a little water around them, make sure to dry it off now.