Got a bit wound up today coming into the beach. Before I knew it I was in waist deep water and resorted to the old fin maneuver of doing a wheelie to stop. Doesn't work on a foil--you just foil out and and then stall straight down. I descended straight down into the soft silty bottom and felt a crack. I think the fuse hit the bottom tail first. Turned my board over and the fuse and snapped off the mast--sheared the bolts off flush. Fortunately a swimmer found the fuse and wings intact on the bottom. Good lesson--slow down early.

Now I'm trying to figure out how to remove the sheared bolts from the fuse. This is a Slingshot standard aluminum mast. Are the bolts truly titanium? Any tips on how to remove them without messing with the threads? Thanks for ideas.

Should be relatively easy just use an extractor drill bit

Lesson noted.

This AvE video might be a start...

Marc
If you have kept up the lanolin grease or Tefgel on the bolts It's easy to back the sheared off bits out with a pointed tool or even a small screwdriver

Try a small centre punch & hammer, tapping gently at the outer edge of the bolt in an anti-clockwise direction until a couple of thread come out, then grab them with pliers or vice-grips.
If they don't look like moving there is probably corrosion in there so will need heating up a bit. Do not exceed 400 degrees!
The dissimilar metals will expand at different rates & crack the corrosive seal.
This will destroy the resin plugs that keep the water out but not a big issue.

Failing the above go to plan "B", Drill & Easy-out as per the video.

I had one of the bolts snap while replacing the front wing on a Naish. I got it out with really meticulous drilling, starting with a small expensive drill making absolutely sure it was centred, I then went a size larger, and then larger again. Taking extreme care to ensure it was centred. I was then able to pull out the remaining spiral of thread, clean with a 6M tap and good as new. I was sure it was going to be catastrophe. In your case the drill might catch and push the remaining thread through, which may not be a bad thing. Now I use Tefgel.

Marc, bummer... FYI, I always foil with a leash. Great that the swimmer retrieved your kit.

Sounds like a missed a great day.
Cheers, Dolf

Just another reason to stop using relatively brittle titanium and start using stainless steel.

I'm not convinced the slingshot hardware is actually titanium. Certainly not a half decent grade of it.

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Grantmac said..
I'm not convinced the slingshot hardware is actually titanium. Certainly not a half decent grade of it.

Ironically, it might be pure titanium rather than an alloy such as 3al 2.5v which is stronger (maybe an expert could tell us how much more). This was an issue when titanium bike frames were the thing. Some importers bought cheap pure titanium tubed bikes which were cheaper and checked the "it's made of titanium" box but were inferior to the alloyed tube versions produced by reputable builders such as Litespeed, etc.

Pure titanium: www.aircraftmaterials.com/data/titanium/cpgr1.html
3al 2.5v www.aircraftmaterials.com/data/titanium/ti3al2-5v.html

Read this forum post www.seabreeze.com.au/forums/Windsurfing/Foiling/Slingshot-titanium-bolt-failure?page=2

My slingshot dealer sent a new mast, my bolt failure was not "wheelie near the shore" induced.

Then the sheared bolt came out with the punch unscrew method. Ezi out did not scratch the surface.

If you can, find a big metals scrapper and ask them whether they could determine the alloy with either a spark spectrometer or a EDS x-ray fluorescence spectrometer. Either of those could tell you the alloy makeup in about 18 seconds.

In my working days, I used an EDS to identify alloys.

Thanks to all for the tips! I started with the easiest method which fortunately worked: sharp punch and hammer, carefully turning the bolts out, tap by tap. I'm glad that I had used lanolin oil--the bolts turned easily.

Thanks also, oscardog, for the reference to the thread on titanium vs. SS bolts. I had tightened the bolts before the session, so slop was not an issue in the breakage. From that thread, it seems like the consensus is to replace the bolts with SS (too bad I already ordered some Ti bolts. I will now order high grade SS....and also avoid "wheelies near the beach!" And just to confirm, my fuse with i76 and 42 wings sank to the bottom, fortunately waist deep. Also considering a leash of some kind from board to fuse.

Think we should all use SS bolts, and change them at the same time as we change the batteries in our smoke detectors.

yes get rid of the brittle SS original bolts I use star head stainless steel bolt you can get in packs of 10 from Bunnings. Staino seems softer. below is the result of getting cleaned up in the shore break coming in. bolts didn't snap just bent a bit.

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allesad said..
Marc, bummer... FYI, I always foil with a leash. Great that the swimmer retrieved your kit.

Sounds like a missed a great day.
Cheers, Dolf

This is the mast to fuse connection so wouldn't have saved it.

Leash from board to mast, leash from mast to fuse, leashes from fuse to wings

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Bender said..
yes get rid of the brittle SS original bolts I use star head stainless steel bolt you can get in packs of 10 from Bunnings. Staino seems softer. below is the result of getting cleaned up in the shore break coming in. bolts didn't snap just bent a bit.

bloody hell ben
was that yesterday arvo,s effort.

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ratz said..

Bender said..
yes get rid of the brittle SS original bolts I use star head stainless steel bolt you can get in packs of 10 from Bunnings. Staino seems softer. below is the result of getting cleaned up in the shore break coming in. bolts didn't snap just bent a bit.

bloody hell ben
was that yesterday arvo,s effort.

They don't call him Bender for nothing

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ratz said..

Bender said..
yes get rid of the brittle SS original bolts I use star head stainless steel bolt you can get in packs of 10 from Bunnings. Staino seems softer. below is the result of getting cleaned up in the shore break coming in. bolts didn't snap just bent a bit.

bloody hell ben
was that yesterday arvo,s effort.

Nah mate that was mid summer. You should have joined me yesterday arvo. The outer harbour swell were cranking