Windsurf Foiling Discussion

[winddude]

Compression of the core foam I bet, I'd get david m to add a layer of kevlar, carbon, and then glass for a lot of tensile strength. Maybe make sure it's not delaminating around the edges of the indent first, otherwise all the reinforcement could just peel away.

[tempy]

Yeah, Dave is opening her up ...

[tempy]

The Joys of Foiling ...

Dave’s work is excellent and he had me back on the board this weekend.

And it was a fun weekend foiling with Tweezer and Paul.

And then I experienced a catastrophic material failure of the bolts securing the mast to the hover glide aluminum top plate.

I didn’t hit anything; I had just come out of a jibe and was pumping ( pretty aggressively) to get onto the foil and “ bam” the foil was gone.

I saw the mast bob and then slip out of my tether and sink to the bottom of NN.

I will be contacting Slingshot to see what they have to say. The tether was in place in case the power box bolt failed, but it needed the collar of the top plate to secure it.

It is, remarkably, all on my gopro helmet cam - the only time I used it all weekend.

When I edit the video I will post it.

I wonder if others have had failures like this? I take the whole thing apart after each trip and rinse, dry and tefgel the hell out of it.

[more force 4]

That's terrible Tempe! I hope you can get some sort of deal with slingshot for a replacement. After the last couple of posts I checked the nose of my board and found that yes, there was a network of cracks right along the nose. The booms never touched but the mast certainly would have bumped off quite a few times. I think I had a hundred or more catapults on that board now, although they're finally getting down to only one or two per session. I've just sealed it up with Marine epoxy for now, but I'm thinking it should get more attention and layers than that.

[winddoctor]

Bummer to hear, Tempy! That really sucks; especially considering you take proper care of the foil system.

[nanmoo]

Bummer bru!!!!

[juandesooka]

oh wow, that sucks! how deep is NN lake at that point? any hopes of getting a diver buddy to help out? or maybe "fishing" with some kind of metal hook contraption ... if the bottom is pretty clean in that area, you could possibly snag it

[tempy]

300 feet plus ....?

[nanmoo]

The boundary layer where it goes completely anoxic is 60’ or so down as well. I’m fairly certain you can’t just dive into that kind of water without some special suit due to significant H2S.

[Keen]

Tempy: one thing that might be of interest is that when I got my Wizard board it came with new Tuttle bolts basically saying don't use the ones that shipped with your foil... that seemed odd to me. However I did switch to the new ones. It was not well explained what the diff was.
Perhaps there was a fundamental problem with the original bolts you have for the plate adapter? I know for the Tuttle bolts they should be titanium and NOT stainless steel. Not sure if all bolts should be Ti. Good luck on a resolution!

The Joys of Foiling ...

Dave’s work is excellent and he had me back on the board this weekend.

And it was a fun weekend foiling with Tweezer and Paul.

And then I experienced a catastrophic material failure of the bolts securing the mast to the hover glide aluminum top plate.

I didn’t hit anything; I had just come out of a jibe and was pumping ( pretty aggressively) to get onto the foil and “ bam” the foil was gone.

I saw the mast bob and then slip out of my tether and sink to the bottom of NN.

I will be contacting Slingshot to see what they have to say. The tether was in place in case the power box bolt failed, but it needed the collar of the top plate to secure it.

It is, remarkably, all on my gopro helmet cam - the only time I used it all weekend.

When I edit the video I will post it.

I wonder if others have had failures like this? I take the whole thing apart after each trip and rinse, dry and tefgel the hell out of it.

[elt]

It's my understanding all the hardware is Time on this foil. I have the Windance foil version that uses stainless. How many sessions did you have on yours before the failure? What kind of maintenance did you perform to discourage corrosion? I would just like to learn from your experience. Thanks.

[Keen]

As a 'concerned' foil owner of same brand that Tempy has (or had) I did bit more digging on bolts. Like others I want to avoid the same fate.

When you buy the Hoverglide plate adpater it does not include the bolts (tappered socket screw). I learned this the hard way when I went to put everything together (this was pre-Wizard / deep Tuttle). When I contacted Windance they said they sell this stainless bolt: the M8 40mm (http://www.windance.com/8mm-x-40mm-Flat ... rew/41600/) that would work. I managed to find these at a local fastener store -- though I was unaware Slingshot was selling something different.
Slingshot is showing a Titanium version on their site (https://www.slingshotsports.com/Hover-G ... lt-Tapered).
I'm not a materials engineer but somewhere there must be a strength/weight/corrosion trade off between these metals. I'm really not sure which is stronger through I'd probably lean toward what Slingshot is selling.

[tempy]

I haven't checked it out thoroughly, but it could be that the bolts I had were the Windance stainless bolts.

Titanium won't "stick" to a magnet, and I know that some stainless won't as well.

I will do a magnet test on the remaining heads that I have on the sheared bolts, for what it is worth.

I would recommend only using titanium supplied by Slingshot. That is all I am going to use.

Slingshot has been very good to me and recognize this was a material failure. I am awaiting delivery of a new foil set from them.

I think the fact that it is clear what happened (from the video); and also that my entire foil kit has remnants of the Tefgel I slather on all the bolts after taking everything apart and rinsing after each weekend, demonstrated to them that I take good care of the gear and that this was not as a result of neglect / corrosion.

Windance recommended, and I am going to take them up on it, that I use this on the next foil. It would have saved my foil and is a better solution than simply wrapping a line around the mast:

http://www.windance.com/NSI-SUP-Rubber- ... tes/13560/

I really like the Slingshot products and their versatility, but cannot stress enough that you have to take care of it and be cautious about "mixing and matching" -bolts / other systems etc.

The enormous stresses caused by the foils are evident - they couldn't lift you out of the water if that wasn't the case - and so it is best to stick with the engineering and not mess with it.

It looks as if there is a happy ending to this story and I cannot emphasize how good Slingshot has been to deal with on this.

[tempy]

elt, sorry, I never answered the questions:

About 15-20 sessions.

After each trip to Nitinat I disassemble the entire system; rinse it in fresh water; let it air dry.

I check the bolts to see if there is any sign of stripping / wear / corrosion.

I then reassemble it ensuring that there is a healthy dose of Tefgel Marine lubricant on all the bolts.

It makes a "mess", but doesn't affect performance.

[can651]

SS machine screws do not do well in shear.
As a rigger and sailmaker I am continuously reminded of the limitations of these kinds of fasteners.

Also, I know that it has come up before but I would remind everyone to isolate SS fasteners and anything carbon (and aluminum) when in a salt water environment. Not just for the threads binding but also SS and carbon interact. We can't put SS rings into carbon sails here in the loft without them immediately rusting. We have to put in titanium rings or address the problem in some other manor.
Paul.