I received a commission project to design and make some awards for a piano music recital Since the request came from my dear spouse, I could not wait to get started. She wanted something like the pendants I have been making but with a musical design. So I had the freedom to do almost anything I wanted.
I created a small pendant designed on the look of a stylish piano keyboard. For the male students I have removed the jump ring eye and will solder a tie-tac stud on the back. Otherwise they will all be the same.
This created the need to make a dozen items all the same all at one time. This is the first time I have had the chance or need to put 8 items on one central core casting tree. (I did do more items using a different smaller tree pattern.) It is S.O.P. in the world of lost wax casting to build sprue trees like these for casting. The big professional casters will easily have 50 or more parts on one central core tree. Definitely not doable in my low production shop.
The design and wax production took two days. the CNC runs totalled about 12 hours run time. I don't have to watch the cutting so I can do other work during the process. If this becomes a popular design, I will make a rubber mold.
Wax detailing and tree building (spruing) takes a couple of hours or more and the investment takes about an hour with a two hour set up (cure) time. The investment actually hardens in about 10 minutes, but there is an exothermic cure period after that.
Firing in the kiln is a twelve hour process with a few hours at 1350 F. degrees. The molds are then held at 800 degrees for the casting process. After all that work the actual casting is about a 10-15 minute process each mold. The work up to this point is all in the preparation.
Then the real metal work begins. This run from the "white tree" stage to finished product (The last three photos.) took a solid 12 hour work day.
It's a long detailed process, but that suits me just fine. I love starting with a concept and creating a detailed finished product. It's like running my multi million dollar construction projects in a microcosm.