I have an issue with my Infinity 99. Its only been used 5 or 6 times, and always with the same (new) fuselage. The issue is that the wing is gouging a bit out of the fuse at the back of the wing. Its 0.5mm deep so far. There also seems to be a slight hairline crack at the front of the foil leading away from the front of the metal plate - but its hard to tell if its structural. Im guessing the wing is wobbling slightly and wearing the fuse. Its never been dropped or grounded. In fact the first time i used it, straight out of the box, I rigged it in B, sailed for 5 mins and switched to C forever after - but I can see the start of the same wear pattern in position B. I have maybe 20x more hours on my i76 and nothing like this to show for it

Has anyone seen this issue before? Does it look like a warranty issue? Thanks

Isn't the fuselage aluminum?, if it is then you are getting electrolysis. My carbon foil mast head flange caused minor corrosion of the board bottom surface under the flange, even though the carbon mast flange was not touching the board bottom- though was 0.5-2 mm away. Cleaned board and wiped a thin layer of epoxy around the board bottom/DT box bottom and no more corrosion.

I don't think that is gouging, I think it is corrosion. Did you use that fuse with a prior wing? I have had corrosion like that on a fuse that I have had for a long time. Not sure if it is possible to avoid, never rinsing my foil after use probably doesn't help. Now I make sure I apply a layer of lanolin to fuse that connects to the wing, not sure what that will do.

Both foil and fuse were brand new in February. Been used 5 or 6 times. My i76 has been used many times more (on a different fuse) and is perfect.

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Smidgeuk said..
I have an issue with my Infinity 99. Its only been used 5 or 6 times, and always with the same (new) fuselage. The issue is that the wing is gouging a bit out of the fuse at the back of the wing. Its 0.5mm deep so far. There also seems to be a slight hairline crack at the front of the foil leading away from the front of the metal plate - but its hard to tell if its structural. Im guessing the wing is wobbling slightly and wearing the fuse. Its never been dropped or grounded. In fact the first time i used it, straight out of the box, I rigged it in B, sailed for 5 mins and switched to C forever after - but I can see the start of the same wear pattern in position B. I have maybe 20x more hours on my i76 and nothing like this to show for it

Has anyone seen this issue before? Does it look like a warranty issue? Thanks

Regarding the hairline crack, I would contact either the shop where you bought the foil from or Slingshot. You might want to take a video of the crack and send it to them. In case it fails, you can go back and say you warned them about the crack.

I think something really weird is going on with the trailing edge on your i99; i could be wrong but it looks squared off and not linear/straight acorss near the stem/fuse insert, looks jagged on that one side- not sure if it's the lighting
but the trailing edge looks really thick. I know of one other case where a guy was sent a "unfinished" wing which hard square trailing edges- but probably very uncommon. I would send those photos along with the crack to them, although the crack is hard to distinguish between a scratch in that pic. Best of luck.

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Smidgeuk said..
Both foil and fuse were brand new in February. Been used 5 or 6 times. My i76 has been used many times more (on a different fuse) and is perfect.

Oh, that does seem a bit weird. Let us know what the shop says.

Thanks for input, that's really helpful. I will see what they say. I hadn't realised carbon / aluminium electrolysis was a big thing - turns out its a huge issue! I think what's happening is the wing is flexing in such a way as to put a point load on the fuse and penetrated the protective black anodised layer. Then there is direct carbon to bare aluminium contact creating electrolysis and exacerbating the problem. I looked up my schedule and the first time this brand new foil and brand new fuselage were used was early June (due to lock down). Its been used 3 times in salt water and 3 times in fresh water. I generally leave it assembled, but often thats with the my wifes i76 not the i99 (and i76 contacts in a different place). Every time its used in salt water its washed off with a hose, and spent at least a month over the summer fully disassembled. If its not getting used for more than a week or two after use in the sea then i disassemble it. All bolts and surfaces are regularly tefgelled (including this problem area - but im guessing the mechanical force of carbon pushing into the aluminium cuts through it. Worse care regime for my i76 (bought 2nd hand so doesnt get the love) over 2 years and a lot lot more use and no issues at all!

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CAN17 said..
I think something really weird is going on with the trailing edge on your i99; i could be wrong but it looks squared off and not linear/straight acorss near the stem/fuse insert, looks jagged on that one side- not sure if it's the lighting
but the trailing edge looks really thick. I know of one other case where a guy was sent a "unfinished" wing which hard square trailing edges- but probably very uncommon. I would send those photos along with the crack to them, although the crack is hard to distinguish between a scratch in that pic. Best of luck.

Yes, those trailing edges don't look right. I had two Infinity 76s sent to me last year like that until I eventually got one that was finished correctly. With square trailing edges of 2mm+ the wings were very noisy and vibrated badly at speeds over 13 knots.