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Hydro-roller
- Thread startertromic
- Start date
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.
It can take a long time to get an up-to-date response or contact with relevant users.
I tried a brief calculation:
Let's say the shaft were: 8 mm / 140 cm, 550 g.
If the stroke of the pump were 60 cm and the acceleration path of the shaft 120 cm,
then there would be with a mean force of withdrawal of bands of 60 kgf force on to the shaft of 30 kgf and speed of the shaft would be about 35 m/s.
There is another good thing. The arrow would not bow for even the greatest acceleration because it spit by the water!
There is one more thing. No shark fins or similar on the shaft so the shaft can be more hydrodynamic. One problem may be binding the shaft as for the "free shaft" or front binding in combination with micro slider which would spoil hydrodynamic as was shown in my tests.
Let's say the shaft were: 8 mm / 140 cm, 550 g.
If the stroke of the pump were 60 cm and the acceleration path of the shaft 120 cm,
then there would be with a mean force of withdrawal of bands of 60 kgf force on to the shaft of 30 kgf and speed of the shaft would be about 35 m/s.
There is another good thing. The arrow would not bow for even the greatest acceleration because it spit by the water!
There is one more thing. No shark fins or similar on the shaft so the shaft can be more hydrodynamic. One problem may be binding the shaft as for the "free shaft" or front binding in combination with micro slider which would spoil hydrodynamic as was shown in my tests.
While searching for something else I found a thread on this gun here:
http://apox.ru/forum/topic/13945-gidroroller-novaja-sistema-podvodnogo-ruzhja/
This gun was briefly discussed on the "Infinite Engines" thread (page 2, post #30) without a great deal of information, but on www.apox.ru they got stuck into it with the usual glee. Here are some diagrams that were not very legible on the Facebook page.
http://apox.ru/forum/topic/13945-gidroroller-novaja-sistema-podvodnogo-ruzhja/
This gun was briefly discussed on the "Infinite Engines" thread (page 2, post #30) without a great deal of information, but on www.apox.ru they got stuck into it with the usual glee. Here are some diagrams that were not very legible on the Facebook page.
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I think it was mainly a case of putting together a new combination not tried before, but the reason for that omission was that no one would have bothered to do it as it is added complexity for no real return. There have been coil spring powered hydraulic guns that have much the same idea, but really only air powered is worthwhile as energy thrown away in the hydraulic section is offset to a limited degree by the low friction and energy losses using a compressed air storage. That way hydropneumatic guns can be around 50% efficient, maybe 60%, but using band storage the efficiency of this hybrid gun would be way less.