My previous bottle bulb was a failure of the good kind. I learned quite a bit so check it out first before proceeding.
This one is simpler to assemble, display and has greater reliability.
Extensive research along with clues from other Instructables members has lead me here...
Please play safe when using compressed gas, deep vacuum in glass vessels and electricity....
Step 1: Materials
Again you will need a clean glass bottle. I chose a clear bottle but a colored one would be preferable
A rough service light bulb.
2 part epoxy
some brass welding rod
A refrigeration schrader valve and stem.
a small section of 1 inch nylon rod.
Light wiring, heat shrink tubing and chain.
You will also need a vacuum pump. not a vacuum cleaner
Argon and regulator
Step 2: Harvest the filament.
That is the main reason for my choice to harvest a filament from an existing bulb.
I chose the rough service bulb since the filament is thicker and has more supports.
The bulb is wrapped in a paper tower and gently tapped with a pointy metal object to break it. The filament along with the glass support is removed.
I chose to shape the filament into a heart for aesthetics. This was done with small pliers and patience. Don not tough or stress the filament or it will burn out.
Be sure to keep the leads long since the silvery pare of the supports near the glass are coated with zirconium which helps with any left over air that wasn't removed, more on this later.
It needs to fit through the neck of the bottle.
Carefully lay it aside for later.
Step 3: Make the seal
I used a scrap piece of 1 inch nylon dowel.
The dowel needed to be cut down in diameter. I used a one inch hole saw followed by a 7/8 inch hole saw then trimmed off the edges.
It is important to have snug but not friction fit. If the plug is too large the bottle neck will break. The combination described above was a perfect fit for the bottle that I chose.
The center hole from the hole saws was drilled all the way through using a 1/4 inch bit.
There were to smaller 1/8 inch holes drilled to accommodate the bulb wiring.
These need to be enlarged at the top to prevent an electrical short.
Step 4: Connect the filament.
Cut down the copper tube off of the refrigeration Schrader valve.
Press the brass leads into the plug so that the bent ends are at the top pointing outwards.
Press the Schrader valve into the plug.
Weld the filament leads to the straight ends of the brass rods.
Coat the lower surface of the plug with epoxy.
Carefully press the assembly into the bottle and wait the prescribed amount of time for the epoxy to cure.
Step 5: Make the connections
The hanger was made by tightly wrapping a short section of the brass welding rod around a 1/2 inch black pipe. One end was cut off leaving a couple of coils.
The other end was bent into a hook shape.
The brass hanger was then threaded onto the screw neck of the bottle.
Step 6: Remove the air
The yellow hoses is connected to the vacuum pump.
The blue hose is connected to the bottle.
The red hose is connected to the argon.
The extra vacuum gauge is optional.
The vacuum is run on the bottle for a minimum of 15 minutes then shut off. Leave it for about an hour to verify that there are no leaks. repair any leaks with epoxy if found.
Turn the vacuum on for another 15 minutes then shut it off.
Carefully add some argon to the bottle while still maintaining the bottle with some vacuum. I left the bottle with around 5 inches Hg
Note if there is still air in the bottle the filament will smoke and burn. Immediately shut of the power and re-vacuum then re-charge the bottle.
A small amount of air can be tolerated as the zirconium on the filament leads will capture it.