You’re gonna love it.
Screws from McMaster Carr for stainless and Accu Components if you want marine grade stainless. 16mm is the length you want. I use teflon tape on mine.
You’re gonna love it.
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That mast makes me happy
. I already loved my surge foils but they got a serious upgrade in performance with the 78sss!! Short cord…I’m never going back!!
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Yeah I apologise for those small screws, this is what is supplied by Stringy and I just don’t have any others at the moment. I do swap out the 8mm bolts when I can though with the torx heads.
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you can try here also.
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There’s only 9.5mm of threads in the adapter and the 16mm bolts get 9 of them. I like 1.5 times the bolt width for depth for security and to prevent stripping which is exactly that. Ti is awesome. However, in this circumstance that extra 1mm has more value to me than the Ti attributes.
I’m sure you do like that. It has been shown many times that a validated rule for threaded joints is that 3 threads carry 90% of the load and all of the load is resolved by 7 threads engaged.
For M6x1 fasteners (1mm per thread pitch), 3mm thread engagement depth would be considered the absolute minimum. Anything more than 7mm thread engagement is considered useless.
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I agree that static strength calculations show the first several threads carry most of the load. My concern is less about ultimate strength and more about long term durability. A foil adapter gets assembled hundreds of times over its life, often by people without perfect technique. Since the aluminum threads are the wear item, I’d rather maximize thread engagement and preserve the adapter than trade that margin away for the benefits of a titanium bolt.
I’m thinking real world service life for 1000s of users. Not theoretical load capacities.
M6x16 appear available here
In regard to strength, not sure it’s needed but also on board with maximal thread engagement on the adapter that is aluminum and cycled many times. For my adapter the m6x16 would kiss the mast so had to use m6x15. It was very few turns like 3.5-4 that actually engaged.
This also I presume is where a TI adapter Jondrums is making could be much more bomb proof. Those few aluminum threads scare me!
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For full strength, its 1.5x bolt diameter. For a mast you really want at least that. 3 threads supporting the majority of the load assumes that there is 1.5x diameter engagement. Since the first couple threads can be easily damaged or loose, full engagement is critical - for M6 that is 9 turns min.
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thanks for weighing in Chris
Code with the apparent metal foot interface. I wonder if they could actually have it removable and then support skinnier fused front wings with the same mast? Screws still could go into mast to avoid the low engagement issues seen with other adapters.
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Can’t tell much from that, however someone is posting 8mm screws for the mast, which is very small. Our screws are 35mm
Seems like a plausible explanation for the metal on that mast.
I have it on good authority that lift has some proto wings that use a shallower fuse pocket with a backwards compatible adapter. You can see it in this photo on the mast of the left.
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That code and lift idea seem sensible as a bridge to a sleeker eventual setup
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You sure they don’t mean M8 screws?
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Yeah, 8mm countersunk m6s have very little thread…
Though M8 would have negative implications to backward compatibility I think
How does this compare? 14mm and doesn’t list chord
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It says 105 mm chord in the text section. Would assume that’s the same for all sizes.
Apparently you can switch out the titanium connection and replace it with one that fits another foil brand. Pretty interesting.
Edit: but how is the interface between the titanium piece and the carbon? Doesn’t this just reintroduce the issues you solve by having a tuttle connection?
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