Yes you can make your own earring posts. It is generally more cost effective to buy them, but making them is not a problem and there are times that it is useful to know how.
1) draw your wire down to the size you want. Maybe .9 mm.
2) Anneal the wire carefully (avoid hot spots-local overheating). Robert Kaylor anneals wire coiled up in a tin can, playing the flame on from the outside to avoid localized overheating.
3) Clamp one end of the wire carefully into a vise, grip the other end with draw tongs or vise grips or toothed pliers and pull gently and hard, stretching the wire-you will see it visibly stretch. This will straighten the wire instantly.
4) Get a piece of brass hobby tubing about 3″ (7cm) long, cut one end to a 45 degree angle or so, anneal it, about one inch (2.5) cm below the flat end of the tube make an indentation with a center punch and then drill a one mm hole at the bottom of the dent. This will serve as a funnel to feed the wire into the hole (and the tube). Then gently squash the tube near the dent and hole at 90 degrees thus making the tube into an oval at that point. The dent with the hole in it is a one of the ends of the oval, on the short curve of the oval. You adjust the squish on the tube until when the wire is fed in and then snipped off flush with the tube the piece that is cut off is the correct length for your earring posts.
5) Then stick the angled end of the tube into a hole you make in the top of a film can. Now when you feed wire into the hole in the dent it slides in until it hits the far side of the tube, is snipped off flush with the outer side of the tube at the dent. It then falls naturally down the tube into the film can.
You can then clamp the film can in place gently in a vise and cut the right lengths of earring posts as fast as you can feed the wire into the hole and snip. You will find that because we made a funneling dent leading to the hole into the tube that when you snip it the wire you are feeding in will automatically slide into the tube and stop again ready to be snipped. The wires gather in the film can. The procedure is very fast and smooth.
6) Now flatten the both ends of the wires (give them a right angled flush end). Use a Zipee® belt sander (my favorite) or a sanding or separating disc on your flex shaft which you push the wires onto (hint-use a tool to hold them-they can get really hot) or as I might do sand them flat on the cardboard disc sander. This is a quick job to do the whole pile or earring posts you have made.
7) You will need a #30 flex shaft handpiece or an equivalent Jacobs Chuck type handpiece for the next step. The wire is chucked into the flex shaft with about 4mm or a quarter inch showing. (see the ‘Small tools’ article in the tips section for how to make a chuck key for prouction use of the #30 type handpiece)
8) Press the foot pedal and rotate the wire in the handpiece at medium speed. You then make the indentation for the ear nut on the wire by pressing onto the wire gently with a side cutter (go gently-you can easily cut off the wire instead of making a groove), or round nosed pliers pressed in to the turning wire, or a triangular needle file held onto the spinning wire or my favorite solution: a pair of side cutters one has altered the jaws on with a separating disc or a diamond burr, so that there is a small hole in the cutters. This last is fast and sure and does not require much skill or thinking, always a useful attribute in a production situation.
This hole lets you clamp the cutters onto the ear wire, make the correct depth groove quickly and without skill requirements and be sure of not cutting off the end of the wire instead of grooving it.
Although I prefer to put the groove in before soldering the ear post on some people solder the ear wires onto the piece and then put the groove in by hand with side cutters, clamping gently and swinging them around the post back and forth to make the groove at the end. Of make the groove too deep into the wire and so weaken it and cause it to break-you should aim for a pretty shallow groove.
9) Once the groove is made in the correct place on the ear wire in the flex shaft then hold a 220 grit (medium) emery stick against the end of the wire as it spins, moving it constantly so as to quickly round off the end of the wire. A cup burr held onto the rotating wire end will also round it off. You may then hold a piece of leather or felt with polishing compound against the wire end to give it a hint of polish as a finishing touch.
Some people will use a triangular file to make the groove instead of snips, try which works best for you.
10) When you are going to solder the earring post on use the earring post tweezers to rapidly clamp the earring post. A pair of the cheaper, chrome plated steel self-locking tweezers with a triangular notch filed in place at each of the ends automatically grips and snaps earring posts to a right angle for quick earring post soldering. To use them one simply throws the earring posts onto the table and they are easily and quickly held at 90o no matter what angle they are gripped from. Note that the ends have been filed so that when using them they smoothly grasp and guide the earring post into its groove.
Clamp the earring post near the notched end. While clamped in the tweezers rub the far flat end on an emery stick to clean it for soldering (good solder joins require recently bared metal), then dip the bared end into flux. Have your solder chips lightly pre-flused on the brick. Gently heat the fluxed post end until the flux on it goes glassy, then touch it to a pre-fluxed chip. The solder chip will stick to the hot wire end. (Do not point the flame at the other solder chips-we need them pre-fluxed but unheated in order to most easily stick them onto the wire end in the way just described). Lift the wire away from the soldering surface and gently heat the end until the solder melts onto it. Then heat the fluxed object itself. I usually take a small round burr and just touch the back of the earring where I want the post both to bare the metal for a better join and to increase slightly the contact surfaces of the join to improve strength.
As the earring gets hotter watch the flame where it leaves the metal If it turns orange as it leaves the metal you are around 800-900 degrees F and can bring the earring post into the flame area. If your metal is glowwing red you missed the orange flame and it is defintiely time to bring your earring wire into the heat. Do not point the flame at the earring post at all (you might melt it) but keep it on the earring. When you think the earring is hot enough place the earring post (bracing the heel of your hand nearby so as to steady it while it solders in place). Let the heat from the earring itself rise up and draw the premelted solder on the post down thus joining it to the earring.
Make sure it is vertical. Remove the heat. Quench the earring in water. Immediately test the join with a pair of pliers. Now is the time to find out you if should do the join again, not later. To test it take your flat nosed pliers, grip the top (notched) third of the earring with the pliers on at a 45 degree angle (this gives a good broad area of grip on it so you don’t dent or scar the wire post). Twist the post 360 degrees around (yes thats right) and back again the same amount.
If the post didn’t fall off the join was good. If it did fall off now is the time to solder it again. This also hardens the post in its bottom two thirds (because the post was annealed during soldering it is dead soft-therefore it doesn’t matter how hard or soft your wire post was before you soldered it on).
There, you are done. If you are moving quickly and you have everything set up to go you can make good earring posts very rapidly and perhaps even competetively with some commercially produced sources. I mostly do this for gold posts now if I need some and I don’t have commercial ones around. There was I time when I did it for silver posts too, not really economical but it worked.