Casting
Lost Wax Casting Process - video slide show
This 6 minute video slide show summarizes the main processes involved in lost wax casting.
- Casting Process Slideshow: Photos of casting lessons showing mostly the highlights of the investment process and spin casting setup. More will be added to this over time.
How To Calculate The Casting Metal Amount
The amount of metal needed to fill the mold = (W x SGw x SGm) + 6.4301 grams.
When:
- W = Grams of wax or other model medium.
- SGw = Specific gravity of wax or other model medium.
- SGm = Specific gravity of metal used for casting.
The following example uses wax as the model medium and sterling silver as the metal.
Let’s say that the weight of the sprue base, model, and sprues comes to 325 grams. The base weighs 144 grams. 325 grams minus 144 grams equals 181 grams of wax model and sprues. Wax has a specific gravity of 1. Sterling silver has a specific gravity of 10.4.
- So, 181 grams x 1 x 10.4 = 1882.4 grams of sterling silver.
To ensure there is adequate metal to fill the mold, add 10 pennyweights of metal for the button. A pennyweight equals .64301 grams, so 10 pennyweights equals 6.4301 grams.
- 1882.4 + 6.4301 = 1888.8301 grams.
Round it off to 1890 grams of sterling to fill the flask.
