Those bury lengths don't really apply to kite lines. The lines are always locked into a lark's head knot so the knot is the thing bearing the load. You're never gong to get a straight pull loading the actual splice. That could only happen if you had a loop sitting on a rigid shackle or similar configuration.
Obviously you design the splice to the best standards you can but the individual parameters are not all that important in the scheme of things.
Good point Oz and I used to have exactly that mindset and it has not lead to any issues. However, I have recently modified this mindset after a recent test kindly done by one of the forum members. The test indicated that at least you do need a buried tail. If you don’t have a tail (ie a stopper knot) the strength of the larks head is drastically reduced, and I mean overhand knot levels of strength reduction.
Then if you consider the loop at the LH it is reasonable to assume 50% of the load is on the tail side, and of course if you allow for a scruffy made LH it could be 100% load on either side before slippage.
Of course it is reassuring to know that the LH will generate lots of friction and this helps with integrity but the tail is easy to do and so I would not neglect it if you want to achieve full strength for all scenarios. Having said that you only have to look at the recent test on the short bury on the new Naish bar thread to see a short sown bury working. Would not want to cause too much friction in this thread, seems to be enough of it going around already.
I just wanted to update my post. I've got a little over 30 days on these lines now, many days with multiple sessions. Almost all are foiling in the 20 to 30 knot range - kite sizes generally 4, 5 or 6. I'm very happy. No issues to report.
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Thanks @watercamper for posting such a detailed guide. Do you recall what the size of the Daho splicing needle that you purchased from greenhat[1] was? They only seem to have Large and XL now, and the Daho product page [2] says the outer diameter of the Large needle is 1.27mm . Did that 1.27mm OD needle work well with your 1.1mm line or did you purchase a smaller sized needle?
EDIT: I now see you already specified that you purchased the medium needle with 1.06mm outer diameter, just below your 1.1mm line size. They must have stopped carrying it since. Sorry about my poor reading skills.
Another update. Lines are still going strong. Just finished 120 days of foiling in Baja. That's about typical for me in the winter. Summer usage is between 60 and 90 days. Just saying - the lines are great!
Nice writeup. I splice in a similar way - using a knitting needle to make a big hole. But I would say that it is quicker and more versatile to splice "on a bite" (i.e. do it without having to have access to the other end of the line). The difference is you need to do one extra step to undo the twist, but using an awl to open up the loop it takes only a couple of seconds. A lot quicker than messing with 20m of line to get to the other end. I had a sketch of the process somewhere but I can't find it right now, but will post it when I find it.
Obviously there a lots of ways that produce satisfactory results. As an aside, I recently saw a vid on dyneema climbing line testing. As part of the procedure they tested the strength of just the Brummell lock compared to line/full bury splice strength. The Brummell lock was significantly weaker than line strength. Can’t remember the exact figures, but I did conclude I would not ride on a fly line where a tail had slipped and the lock was fully loaded. ( Have ridden, not jumping,with this scenario on a 3mm pig without issue!)
I do enjoy splicing and making a nice clean setup, especially for heavily loaded bars.
However, it is curious to know how little strength is needed for strapless surf foiling on smaller kites. I have one bar with 200lb/90kg test braided dyneema fishing lines with the ends just overhand knotted into loops(no splice) and haven’t had any issues. The first part of the line to wear out is where they cross when kite is looped.