Air tank

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Hi all, i have a question: has any one ever built a air tank from a coke bottle? i have been told this can be done, but no one seems to know how.

Thanks for any help

Rob
 
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Edgar Brooks

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You wouldn't catch me putting compressed air into something made of glass, or plastic.

Edgar
 

stona

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Me neither.

I'm aware that some people use C02 as a source of "air" using the sort of bottle more usefully used for pumping beer from the pub cellar but a coke bottle?

Steve
 
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dubster72

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I'd definitely not try this! A plastic bottle under pressure doesn't bear thinking about!
 

stona

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I know exactly how a plastic bottle explodes. We had fun with this a few years ago.

This is me (wearing a protective mask and natty Adidas tracky bottoms!) and some of the technical crew from the X Factor in the old car park at what used to be The Point in Dublin before it was 'remodelled'. We are using dry ice in plastic bottles to power a mortar tube,nicked from the pyrotechnic lads. The last explosion is just a 2l coke bottle.

Don't try this at home!

cheers

Steve
 

spanner570

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Great video Steve......I reckon that should answer Rob's question better than any words!lol

Incidently, I've just seen my dog outside trying to give a plastic chicken one on our lawn.....and the he is a she. I really must have a quiet word with her.......

Cheers,

Ron
 
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m1ks

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\ said:
I know exactly how a plastic bottle explodes. We had fun with this a few years ago.This is me (wearing a protective mask and natty Adidas tracky bottoms!) and some of the technical crew from the X Factor in the old car park at what used to be The Point in Dublin before it was 'remodelled'. We are using dry ice in plastic bottles to power a mortar tube,nicked from the pyrotechnic lads. The last explosion is just a 2l coke bottle.

Don't try this at home!

Funny video but, swear warning to all with kids in the house.

Clicked this on with my 7yr old sitting next to me on the sofa and had to shut it off quickly due to someone exclaiming their joyousness in profanity.

Don't mean to sound like an old fart but trying to explain why someone in a car park is yeling.........., not fun. :smiling3:
 

stona

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Sorry M1ks,

I should have warned of some fruity language. With an Aussie,a Belgian and a Scouser present along with yours truly(who isn't the culprit) it was inevitable!

Cheers

Steve
 
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m1ks

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That's OK Steve, i know it wouldn't have been intentional on your part, (i figured it wasn't you doing the yelling).

Thankfully he was partially engrossed in some Lego Ninja thing he's currently into and I managed to convince him the fella had said something about 'cooking' A explosion, :smiling3:
 

Ian M

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I read somewhere, or maybe saw it on the box, that a 30cl bottle filed with dry ice is equal to a cubic metre of CO2 in gas form. This is the reason for the violent explosion as the solid rapidly expands to gas which is exactly what an explosion is. The rapid expansion/conversion of a solid into a gas.

I to would advise against trying to make an air tank out of any thing other than a metal container made for the purpose of pressure storage. Be it an expansion tank, gas bottle or the like.

Just as an idle question does any one know the psi required to bust a plastic coke bottle?

Ian M
 

stona

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\ said:
Just as an idle question does any one know the psi required to bust a plastic coke bottle?

Ian M
It's a lot!

That 2l coke bottle had a couple of cms of dry ice chips and then a few more cms of water in it. It took a good 5 mins to explode and had visible changed shape before it went. The bang was so loud that someone called the Gardai which spoilt any further fun.

The only saving grace is that there is no shrapnel and no fragments!

On another occasion we fired a cricket ball from a mortar powered by a small coke bottle and dry ice. After some calculations based on times to maximum height and back with various corrections we estimated that it went up somewhere between 75 and 85 metres,over 250 feet!

Cheers

Steve
 
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Oggy

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While it is good to see people erring on the side of caution, there is no reason why air reservoirs should not be made of plastic or glass PROVIDED they have been designed and tested for the purpose.

Retractable undercarriage on RC aircraft is powered by electricity or compressed air. In the latter case, the model will have a plastic air reservoir looking like a drink bottle which is pumped up to up to 100 PSI as required.
 
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