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Tomba - All in One barrel sealing

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
Streamlining of the line slide, or slider, is important as Mares had the University of Genoa (relying on my memory here as I have not rechecked it) conducted hydrodynamic testing to arrive at the shape of the slider used with the original "Cyrano". An effective hydrodynamic shape cannot solely be determined by the appearance, although a reduced cross-section presented to the flight direction is important, it is not everything. That "Cyrano" slider had the line angled and blended into the body shape in the manner in which it was tied, the problem with it was that it was not strong enough if used with other types of line and it also had to be tied properly to achieve the correct flow dynamics at the velocities it was designed for. Hence the trailing shape of the slider is important and I think this is being shown with Tomislav's rear cone as long as vortex inducing stepped transitions are eliminated from the rear shape to create the best flow lines. Think of the shape of a Tuna, that fat "teardrop" shape in side profile which has produced fast swimming, low drag capabilities over millions of years of evolution.
 
Yes Pete, the trailing shape of the slider is very important for the best shooting performance.
Stepped transition of even 1 mm spoils the shooting performance significantly!


 
Here is one more interesting image.
Difference between vacuum barrel and water barrel was only 9% points... ? Maybe this result is not very reliably because I did only three shoots having vacuum barrel. I was not interested in differences vacuum - water barrel, this time.
From earlier measurement, few years ago (https://forums.deeperblue.com/threads/tomba-all-in-one-barrel-sealing.81791/page-3#post-783345) the difference was about 25 %
I also accidentally measured the low power energy. I forgot to switch power regulator from low to high before measuring vacuum barrel performance.

 
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This is an idea for a new stainless steel slider that could be used with TombaF800 adapter for 8 mm free shaft, of course in this case using 7 mm shaft with tang 8 mm, and PU shock absorber.
The part of the slider on the right side must be glued or silver soldered. This slider is for 1 mm mono or dyneema.


 
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My first test of Tomba free shaft in year 2009.




Tested in sea, year 2017. The best result on test.





Redy for next test using TombaF800 free shaft kit.

 
Reactions: foxfish
Last image above is actually variable cross section (knot) line slide.
 
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