Items can be soldered onto a glass bottle stopper as long as there is metal present on both items. This method is used to create decorative bottle stoppers. It is important to use metals that can easily be soldered; aluminium and iron are very difficult to solder. Soldering uses high heat to melt a piece of metal onto the tow items to be joined. The melted metals acts like glue and sticks the two metallic pieces together.
Choose the correct soldering alloy for the metal on the bottle stopper and decoration. The type of solder needed depends on the application. Cadmium-silver is used for soldering aluminium. Cadmium-silver and lead-silver are used for high temperature soldering. Bismuth is used for low temperature soldering. Tin-antimony is a good choice for wine stoppers as this is non-toxic and frequently used in the food industry.
Wet a sponge and set this near the soldering iron. The sponge does not need to be overly large. The purpose of the sponge is to wipe any excess solder off the soldering tip. You want a sponge that is large enough to hold so that your fingers do not come in contact with any solder material. For soldering that takes a long time, leave the sponge in a small dish that contains a few inches of water. This prevents the sponge from drying out.
Lay down a protective surface where you are soldering in case you drip any solder. Do not use plastic or any other material that will melt when the solder material drips on the surface. Instead items such as cardboard or even a sheet of spare plywood will stop any drips from damaging the table or surface you are working on.
Turn the soldering iron on and allow it to heat to temperature. Cover the entire tip with solder when it is at the necessary temperature. This will use a lot of solder and it can drip. It is better to have too much than too little solder as any uncovered bit will collect residue and this reduces the soldering tip's ability to conduct heat. Wipe off any excess solder with the wet sponge.
Clean the glass bottle stopper thoroughly. Use a heavy duty cleaning pad to remove any surface tarnish. Do not use pads that contain soap or cleaner, use industrial pads. Use steel wool to remove any stubborn bits of deposit on the bottle stopper.
Wet a cloth with acetone and wipe down the bottle stopper. Blow compressed air over the stopper to remove any debris that has collected in holes.
Position the decoration on the bottle stopper. If possible clamp this into place. Apply a small amount of soldering to the tip of the soldering iron. Place the soldering tip on the bottle stopper and the decoration. Heat both areas for a moment so the solder sticks to the metal.
Place the tip of the solder wire onto the bottle stopper near the soldering tip, but do not touch the soldering tip. Move the solder and iron along the contact points to form a joint. Remove the solder and then the soldering tip. Allow the solder metal to cool. It takes a few seconds for the metal to solidify. Apply heat and solder in this fashion until the decoration is securely fastened to the bottle stopper.
Soldering produces vapours: some with are toxic depending on the type of solder being used. Work in a well ventilated area. Personal protective equipment is also important as the soldering iron reaches very high temperatures.