pwf tells about the stazione di carbonatazione he and Simas made for the Lithuanian Association of Cinematographers NY ball.

Left: an attempt to TIG-braze a bronze ¼ NPT fitting to a 8 mm stainless steel tube. A total failure. Right: same stuff soldered with high-temperature solder used for copper plumbing systems.

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A CO2 feed tube TIG-welded into its place on a stainless steel top plate. The black O-ring seal for the bottleneck sits in a groove drilled using a hole saw. The small hole on the left is for CO2 exhaust from the bottle.

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The top plate on its own. The bent tubes are for CO2 venting. The gas flows into the plastic bottles through the straight tubes.

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The top plate with its steel frame.

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Welding the steel frame.

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The assembled system. The hose on the left feeds the gas from the gas cylinder (right). Plastic bottles were used for safety reasons. We had information that they can easily withstand pressure up to 8 atm. Gas input is individually controlled by ball valves for each bottle. For each output there is a manometer showing pressure in a bottle and a needle valve that is used to adjust the gas flow/pressure through a bottle. It would be enough just to fill the bottles with CO2 and let them stand for a while, but bubbling CO2 is cool.

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With optional LED lighting and dry ice:

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