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Vacuum Crossbow - No limbs, no rubber.


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Old 08-29-2014, 02:27 PM   #21
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when it was available, price was > $2K US, unfortunately all traces of the company have disappeared


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Old 08-29-2014, 03:35 PM   #22
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Vacuums suck.

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Old 08-29-2014, 04:03 PM   #23
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Apparently his Mk. I version used a steel spring - but with steel cable string and steel spring its not the fastest out there. Rubber will be faster. Jörg has numerous designs that would outperform this one I think.

He disassembles it at the end of the vid. The vacuum is an ingenious idea but requires a fairly large tube to generate the necessary force. Also no force multiplicators like pulleys or levers are used.


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Old 08-29-2014, 05:25 PM   #24
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inspecting the audio tape the average arrow speed is about 195FPS or 59m/s at 50m for the vacuum crossbow
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Old 08-29-2014, 10:53 PM   #25
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Quote:
Originally Posted by Arturo Borquez View Post
inspecting the audio tape the average arrow speed is about 195FPS or 59m/s at 50m for the vacuum crossbow
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195 fps is pretty fast.

Was the arrow weight mentioned?
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Old 08-30-2014, 12:27 AM   #26
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Quote:
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195 fps is pretty fast.

Was the arrow weight mentioned?
Fast as my 50lb Juaguar, about arrow weight I don't know but penetrating a 2mm thick steel needs some serious momentum ...
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Old 08-31-2014, 08:20 PM   #27
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He used heavy arrows, about 55 grams,so at that speed,they have some serious powa
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Old 08-31-2014, 09:02 PM   #28
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He used heavy arrows, about 55 grams,so at that speed,they have some serious powa

849 grains at 195 fps = 71.6 ft-lb KE and .73 momentum

That will kill anything that walks.
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Old 12-10-2014, 03:49 PM   #29
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Well. That was cool. I could learn a thing or two from you people. Literally. Pressure, vacuums, and all that stuff... no within my usual realm of study.
Never even heard of a vacuum weapon before.
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Old 12-10-2014, 03:57 PM   #30
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BTW, anyone heard from BoyntonStu recently?


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