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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.
Finally, I think, after numerous possibly design, this might be the best solution!
Very important is detail of piston in yellow circle. This makes hydro damper much more reliable and makes it possible for any braking distance length. Distance "Lu" is for taking water for hydro damper, during loading the spear.

 
I made the simplest and the most user friendly design of TombaF700HD (Hydro Damper) for 13 mm piston.

 
What is the most interesting in this last design is that the elastic rubber hose and holes in muzzle are replaced with two 2 mm hols in piston! I am sure it would work. Maybe there will be some fine tuning before realization.
 
Thanks for sharing.

Keep up the good work Tromic.
 
Result will be soon, I hope so. If I am not mistaken in the calculation should work good. Damper works with 0.5 g of water! I'll try a gun in air. First I have to put a little water in the head and then the water is injected with the spear, always the same amount. Any excess of water will be removed when loading the spear.
 
During loading the shaft, on distance "a" undesired water is being removed from the muzzle. On distance "b" water for hydro shock absorber operation is injected into the muzzle. All this water (a, b) would be undesired/harmful in guns with classical shock absorber of any kind.

 
So; what did the test show - is your new clever system with the two 2mm holes working as it should?
My greatest respect for your amazing work,
Jegwan
 
Jegwan said:
So; what did the test show - is your new clever system with the two 2mm holes working as it should?
My greatest respect for your amazing work,
Jegwan
Click to expand...

Thanks! I have not made a test yet, but I hope it would be made very soon. I am pretty sure it will work fine. There are actually two 1.5 mm holes (to make it easier to polish it, not to shave the O-ring), but the hole through the shaft tail is 0.9 mm. Last summer I did a similar test with hydro damper and it was succesful.
 
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I got an very simple idea from all the talk about holes. Maybe you have already tried it. My idea is to make a longer tail adaptor and drill a longitudinal channel inside of this ending in one or two transversely water relief holes located on the other side of the "O"-ring. Then you don't need to drill holes in the piston. Do you follow me?
 

Don't you think it is easier to drill a hole in a piston? This holes are actually supposed to be water entry ports, not water relief ports. Holes in a shaft tail are water relief ports. Thanks, anyway. Every idea is welcome!
 
Ok. I guess you're right. Just a thought.
 
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Great! The loading looked a little hard or was it as usual? Looking forward to the underwater test when this is possible. I seems like you have the same cold weather as we have here...
Regards,
Jegwan
 
Jegwan said:
Great! The loading looked a little hard or was it as usual? Looking forward to the underwater test when this is possible. I seems like you have the same cold weather as we have here...
Regards,
Jegwan
Click to expand...

Loading would be easier under water. Shaft was missing lubrication. After shooting I inspected piston and damper body condition using magnifying glass. Everything was OK, after 2 shoots.
 
That's sounds promising. It's a little difficult to evaluate the sound in open air on the video, but I think the shot sounded quite silent and not like the piston was "banging". Good job Tromic.
 
Jegwan said:
That's sounds promising. It's a little difficult to evaluate the sound in open air on the video, but I think the shot sounded quite silent and not like the piston was "banging". Good job Tromic.
Click to expand...

I have not shoot pneumatic speargun in air before so I did not know what to expect. I will see it in sea on summer.
 
Reactions: Jegwan
tromic said:
I have not shoot pneumatic speargun in air before so I did not know what to expect. I will see it in sea on summer.
Click to expand...

You sure looked like a pro on the video!! Soon you will be hunting birds
 
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