How do I get started dopping with wax?
There are several types (colors) of wax which all have different melting temperatures.
I use the high temperature red/brown wax (some times called diamond setters wax) to dop pretty much everything I cut.
Note: For something heat sensitive like Opal, I would use the low temp dopping wax.
To get started, take a piece of the wax (about 3/8″ square) you are going to use, and put it in a small glass jar (with a good lid) and a couple tablespoons of alcohol (denatured works best and I use it in my alcohol lamp anyway). Let it melt, it will take over night, when you look at it in the morning you will see that it has separated.
There will be some crust at the bottom of the jar, it is basically filler, you do not want it and can throw it away, if you want to. What you are after is the lacquer (glue) which will be floating in the alcohol that you can pour off. When you are ready to dop a stone, coat both the end of the dop and the flat place on the stone that you are dopping to, with some of this lacquer. Let dry for a few minutes, this creates a pre-bond and will help you adhere the two together.
Next melt some wax onto your dop, coat the whole end of the dop, I would rather have a little too much wax than not enough. I use a alcohol lamp for this stage, because it is easier to control the heat. DO NOT bubble and/or smoke the wax, if it does this you have used too much heat and taken the temper out of the wax, start again. You want the wax good and runny, but not boiling. Keep the wax on the dop by turning it, when it is hot enough and melted, stick it to the stone. This will not give you a great seal yet, all you are trying to do at this stage it to get them to stick together. If they do not stick, the wax was not hot enough. Try again. Some people heat the stone a little bit to help them stick the first time, but I prefer not to.
When it sticks, gently hold the dop and stone above the flame and turn constantly until the wax kind of seems to slump and seal. Be careful, if you heat too much the stone will fall off and you will need to start again. You want the wax/stone/dop joint to get the heat evenly and gradually, hold it about an inch above the flame and right at the stone/wax/seal and keep moving. This is where the practice comes in, and it may take you a few tries to get a good joint. Once you do it a few times and know what to look for it gets easy.
I usually test the joint after things have cooled completely by tugging on it, I would rather re-dop now, than later if I did not get a good joint. DO NOT put them in water to cool. Stones are very susceptible to thermal shock, any sudden heating or cooling will probably cause damage. Let them cool gradually…
Note: I usually use a cone dop instead of a flat dop on the first dop of the stone (on the flat), I think that the extra wax inside the cone helps to strengthen the overall seal. The wax is not only around the dop but it is inside as well, you can use either type of dop (cone/flat) I just think that the cone is a little stronger. You still need to dop to a flat place on the stone and get it level, it is usually not a problem with either dop.