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6x... look what happened

Post questions and info about hybrid (compressed gas with fuel) powered cannons here. This includes discussion about fuels, ratios, ignition systems, build types, safety, and anything else relevant.
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Unread postAuthor: Killjoy » Wed Dec 19, 2007 9:43 pm

Yeah I think a thick piece of rubber should be able to handle the impact force of the piston. And thats fortunate you were able to find parts for repair without much trouble.
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Unread postAuthor: rna_duelers » Thu Dec 20, 2007 1:47 am

Try getting some bumper stop rubber out of a coil over suspension component,they are designed to absorb a lot of shot from bottoming out.The valve spring is also and idea.
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Unread postAuthor: Brian the brain » Thu Dec 20, 2007 3:23 pm

I'm not sure on how a piston hybrid works..I haven't followed the advancements in that field.Anything having to do with combustion ( hybrid or otherwise) is considered a firearm and illegal in my country.
Since I have no complaints about the power of my pneumatics, I haven't looked into hybrids.

I do however have a theory on how one could be made.The picture ( although very schematic and incomplete) should explain.
Fuel meters etc have been left out.

It basicly functions like a piston pneumatic, it is just set off by the ignition.
Add an exaust valve and it can act like both.
As the piston is forced back the pop-off valve( or maybe several, to be safe) exhausts the pilot.
If only I could figure out fueling and stuff, I COULD easily turn my cannons into hybrids.

One thing I do know..pistons should ALWAYS be as light as possible, so that should help your problem

( pneumatics stil have their pro's.It's easier to achieve full auto and they don't give off muzzle flash.Neither will they burn up the insides of a silencer..muhahaha)
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Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
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Unread postAuthor: Fnord » Thu Dec 20, 2007 4:32 pm

Your theory is right, that's how they work.

This is a diagram of what mine looks like after the repairs today. There's not much to it, really. Not even a pop-off valve. (a pop-off releases the air behind the valve, causing the piston to slam into the bumper even harder without a cushion of air to slow it down. So in my case not having a pop-off is a good thing)

I drilled holes in the piston to reduce weight and added a rubber stopper as a bumper. I wanted to incorporate a spring into the bumper too, but there wasn't enough room (reduced the piston travel to ~1/2").
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A coax design would be easier to build, but the barrel would hinder the combustion process.
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Unread postAuthor: Brian the brain » Thu Dec 20, 2007 5:20 pm

wow..

I'm pretty sure I thought of that first some years ago.I don't feel like looking it up, but I'm pretty sure.
I never built it however and I'm happy the idea works so well!!
I disgarded the idea and never gave it a second thought...
That's funny...since I don;t even really like hybrids haha..


I don't mean to brag.. and anyone can use this idea, you probably understand it better than I do anyway..It was just one of those things that popped in my head as people were discussing the subject..

Well...anyway..you are actually saying performance could be improved by the safety valve!! ( you didn't mean to but you did!!)
Please try the "floating diaphram"method...i't so much lighter and it makes the pop-off method possible I think.
You could just use a slab of say 3/8 thick neoprene..without reenforcement.It would probably stand up to the pressure needed for a 6x mix..
Just the neoprene disk would mean no more bumper problem..
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Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
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Unread postAuthor: clide » Thu Dec 20, 2007 10:15 pm

Brian the brain wrote:wow..

I'm pretty sure I thought of that first some years ago.I don't feel like looking it up, but I'm pretty sure.
I never built it however and I'm happy the idea works so well!!
I disgarded the idea and never gave it a second thought...
That's funny...since I don;t even really like hybrids haha..


That's actually how the first* hybrid cannon built by DR worked, except he used a sprinkler valve rather than a homemade diaphragm.

*Could be the second hybrid depending on how you define hybrid.
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