The beginning! Three of our Ridgelines rings waxes, wax sprue, and the rubber sprue base. The ruler will be used later to check dimesnions.
Not pictured is our Dual Therm wax pen.
The first wax is in place. This is our first Ridgelines Ring is a special order for B. through The Jewelers Workbench. (It will be a size 5 1/2 with a peridot mounted for our client when we're finished.)
All three waxes in place. The two outer rings are our third Ridgelines Ring design.
The wax pen is just visible in the background.
Adding molten wax to smooth out the base. This step, one of my favorites, is known as luteing. Molten metal flows very much like water does; there are some differences because of the temperatures involved, but the principles are basically the same. It is very important that there are narrow no choke point that would restrict the flow or cause turbulance when the metal is poured.
All three rings ready on the sprue base. This 3 inch base is a bit large for casting just these three rings, but you'll see why I choose it soon.
A sideview of all three rings in place. Since the wax pen has two stations I'm able to use two different size and shapes of tips at the same time. Which is incredibly handy! The temperatures are controlled with two seperate rheostats.
Top down view with the ruler in use. I'm double-checking to make sure that no edge of any wax is within a 1/4 inch of an inner wall of the flask. I prefer a slightly over-size base and flask because whenever I can I like to have 1/2 inch between any waxes' edges and the flask's inner wall.
Top down view into the flask, ready for investing!
I had to stop as this point. All ready to invest first thing in the morning. Then into the kiln for the burnout cycle, and then casting!
At this stage it's very important to have good records. And I forgot to mention a couple of steps!
First it is important to weigh the empty rubber sprue base before doing anything! Once the waxes are sprued the base is re-weighed. Subtract the empty weight from the finished weight. Since these will be silver rings that number is multiplied by 10.4, which is the specific gravity of the sterling alloy that I'm using.
In this case my casting log tells me that the Total Wax Weight is 2.8 grams. Which comes out to be 29.12 g Metal Weight. To ensure a good casting I'm going to use 35 g to allow for a good full button (the base area).
A good sized button is important because metal shrinks as it cools. The smallest areas will cool and solidify first. The last areas to solidify will be the largest and thickest. By allowing for a large heavy button you help ensure that there is molten metal available for the heaviest areas of the castings as they cool. Otherwise you can have shrinkage porosity to deal with . . .
The last step, before the morning, is to record the dimensions. In this case we're looking at 3" Wide and 2 1/2" Tall (allowing 1/2" headroom above the waxes ~ which helps prevent blowout when the metal is poured).
Knowing these dimensions I consult my investment mixing chart. I'll use 15 oz of investment and 161.7 ml of water. But that's for another day!
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