Bubble lights.

How easy is it to make the bubble tubes and bubble lights so common in
the old Wurlitzer jukeboxes and as Christmas lights? These are the
sealed glass tubes that usually contained methylene chloride with some
glass or chemical granules at the bottom to allow easy vaporisation of
the liquid using an external heater or lamp. The liquid then "boiled"
sending bubbles up the tube where the vapour recondensed back into
liquid again to repeat the cycle.

Do these need a vacuum drawn on them to lower the liquids boiling point?

Is there a safer liquid?

Also, does anyone have a close-up picture of an old Christmas light
called a Peerless Shooting Star which sounds like a mini lava lamp.

 

Wouldn't a small air pump work just as well? There are some higher
quality (i.e quiet) aquarium air pumps that should do the job quite
nicely.

 

Messy. Not a sealed tube and the water evaporates and goes yukky after
time.

 

I bought a set of bubble lights on one of my trips to America a good few
years ago. I guess they probably still make them?

 

I can't answer your question specifically, but I did just put 2 and 2
together: I build display cases and boxes out of acrylic plastic (plexiglas,
lucite ect.) and the solvent cement used is mainly methylene chloride sold
in cans and tubes called "Weld-on". I also have one of those bubble lights
and it says it contains a vial of methylene choride. The light is stored
away and I didn't even think about the cement until you mentioned it.

Anyhoo. The cement evaporates very rapidly that it feels very cold. In the
bubble tube, the continuous evaporation and condensing cycle operates as a
simple refrigerator of sorts keeping both ends of the tube close in
temperature as the the heat is carried away through the cycle.

The solvent cement is known in the state of California to be cancerous, but
so is about anything else. Because of the chorine content, it is
nonflamable, but has a strong odor.
John

 

It's actually the State of California itself that causes cancer. The
warning labels on everything from running shoes to finishing nails to
canned peaches are just there as a ruse.

 

I restored a couple of old Wurlitzer jukeboxes some years ago. The original
bubble tubes were filled with ether and the bottoms were set in wirewound
resistors to heat the fluid. I believe that the parts, the technology, and
makers of custom tubes are available through the few jukebox collector
newsgroups.