There are about as many casters that recommend vacuum casting as
there are those who recommend centrifugal casting. I know I will get
some comments from those who centrifugal cast. The one thing they
cannot do better when centrifugal casting then I can do vacuum
casting is listed as item 6 below.
I have done vacuum casting since I started making jewelry. I favor
it for the following reasons:
If you buy a vacuum pump for vacuuming the investment you have
the primary tool to do vacuum casting. All you need is a vacuum
plate to set the flask on.
You can cast much larger items with the vacuum set up. I have
cast up to 32 ounces of silver in one shot. I am limited only by the
amount of metal I can melt at one time.
I think you can control the flask and metal temperature to a
tighter tolerance if you vacuum cast and use an electric furnace to
melt the metal.
The electric furnace will tell you the relative temperature of the
metal. It is difficult to know the relative temperature of the metal
within 50 to 100 degrees when using a torch.
There is no delay from the time you remove the flask from the burn
out oven until you pour the metal when you vacuum cast. When
centrifugal casting the flask temperature will vary if you have to
heat the preheated metal to the pour temperature after the flask is
placed on the arm. The flask could cool or heat up while the metal
is melted depending on how you direct the torch.
Less head space above the wax is required for vacuum casting.
Vacuum casting uses less investment.
The weight of metal in a pour is less critical when vacuum
casting. You don’t want to sling too much metal when centrifugal
THE ABILITY TO PREVENT FIRE SCALE IS PROBABLY THE BIGGEST
ADVANTAGE OF VACUUM CASTING. I have prepared a paper on prevention of
fire scale when vacuum casting. I can send it through e-mail if
There is a disadvantage with vacuum casting. More sprues are
required for vacuum casting than are required for centrifugal
just my two cents,