Metalsmithing for Lampworkers — an Online Tutorial
Lesson Three — Annealing and Work Hardening
To begin, read the section on Annealing (page 18) from the book Jewelry, Fundamentals of Metalsmithing by Tim McCreight. However, lampworkers beware...confusing terminology ahead, proceed with caution!
Lampworkers anneal their glass to strengthen and harden it. However, metal behaves the opposite way. Metal is annealed, or softened, by heating it briefly with a torch. Metal is made stronger through work hardening.
To understand this process we need to look at metal at the molecular level. Metal is composed of tiny crystals. When heated at the torch, the molecules move away from one another (expand) then, as the metal cools, the crystals regroup in their crystalline structure, leaving tiny spaces between the molecules. These spaces allow the metal to be easily worked because the crystals have enough "elbow room" to move easily as the metal is worked.
Conversely, as the metal is hammered on, sawed against, drilled, etc., the molecules are forced closer together, making the metal harder to work. Metalworkers will often anneal with each step of fabrication process to keep the metal soft and malleable.
Project II — Headpins and Ear Wires
The best way to make headpins is with a soldering torch. A soldering torch differs from a glass torch in it's lack of a stand. A soldering torch is held in the hand and moved around the stationary piece of metal being worked on. However, a glass torch can be used to make headpins even though it isn't the best tool for the job. (You can melt silver wire on a gas range in a pinch, but again, it isn't the best tool!)
This next lesson will use a glass torch. To begin, review the lesson on Pickle (page 39-40). These are so easy to make it's almost laughable.
1. Mix up a small amount of pickle according to the instructions on the box. Place the pickle in an old crock pot which you will dedicate to metal working. Needless to say it will no longer be safe for food preparation or any other use.
2. Cut lengths of 20 gauge sterling wire 3" long; about the length of your index finger. Note: one of my instructors taught me this: learn the measurements of various parts of your body in order to measure quickly. Your index finger is about 3" long, the width of two fingers is about an inch, the palm of your hand is about 3" square, etc.
3. Take a small amount of paste flux, place it in a film can and mix with a bit of water until it has the consistency of stirred yogurt.
4. Set up your work bench with the pickle pot, tweezers, flux and wire. Turn on your glass torch and put on protective glasses.
5. Using the cross locking tweezers, pick up a length of wire. Dip one end of the wire in the flux. Holding the wire perfectly vertically, touch the fluxed end to the tip of the flame.
6. Within a few seconds the flux will bubble and turn clear then the end will bead up. Quickly remove the wire from the flame and place in the pickle pot. Bead the end of all the pieces of wire in the same manner, placing them in the pickle pot
7. After about 5 to 10 minutes remove the wires from the pickle pot being sure to use the copper tweezers. DON'T be tempted to use your stainless steel lampworking tweezers, you will mess up the pickle over time!
8. Dip the headpins in a dilution of water and baking soda (a process known as "quenching") then rinse under running wire.
9. Lightly sand the headpins to polish them. While you won't have perfect drops on the end and the finish won't be as bright as possible, you have some serviceable headpins. You can use the headpins as they are, dead soft (the process of balling up the ends brought the metal into the fully annealed, or dead soft state) or you can shape and work harden them.
Note: A better method of balling up the ends is to use a soldering torch, holding it with the flame pointed directly at the ceiling. Using the torch in this manner, the beaded ends will be a more perfect teardrop instead of slightly off-center as with a glass torch. Additionally, the easy way to get a bright finish on the headpins is to tumble them in a tumbler. However, these pieces of equipment are expensive and this is a beginners tutorial.
10. To make headpins into earwires, simply shape the soft wire into the desired shape. This is where you can distinguish your work from those who purchase prefabricated jewelry components. Let you creativity go!
11. Once you have the desired shape, place the headpin on the metal block of the bench pin. Keeping the rounded teardrop end hanging off the edge of the metal block, lightly hammer the wire with the rawhide mallet. (Note: before using a new rawhide mallet for the first time, smooth the face of it with sandpaper. Any gouges in the rawhide will mar the metal)
12. Test the hardness of the earwire as you would a spring. If you have work hardened the wire sufficiently it will hold it's shape and not be easily bent. If the wire is too soft, continue working the piece.
13. Finish the unbeaded end by smoothing it with sandpaper.
Whew! That was a lot of work for a bunch of headpins that only cost a few dollars to buy in the first place. You might consider continuing to use purchased headpins in many applications. However, you now have the ability to make longer and heavier headpins, you can make them out of metals other than silver, and you can experiment with new shapes for earwires. Now you can make a pair of earwires for the brass dangles you made in the first lesson!
In the next few lessons we will learn to rivet using handmade headpins. Rivets are very useful for cold joining (attaching two pieces of metal without solder) and can be beautiful decorative elements on their own.
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