I have used nothing but vacuum casting for 30 years. I have cast
every size and detail part with this system without problems.
There are probably as many people who will say centrifugal casting
will give the most detail as there are who will say vacuum casting
will give the most detail.
I have seen spiders that were cast by both centrifugal and vacuum
processes. There was no lack of detail in the spiders cast either
way. Our intuition may make us feel centrifugal casting gives
greater details because the metal is forced into the mold.
I have had some buckles and conchos cast for me by a centrifugal
caster. Most of the items I had cast this way had what I call
stretch marks which could not be polished away. I believe either
method will give you the detail you want once you master the
process. The decision between using either method of casting will
boil down to finances available for buying equipment, safety and the
size of castings you wish to produce. Centrifugal equipment my be
the least expensive way to go but it will limit the size of castings
you can produce.
Some thoughts: If you invest in a vacuum pump to vacuum you
investment you will have the major portion of the equipment you will
need for vacuum casting. Vacuum casting will allow you to pour more
metal into much bigger flasks than you can with the centrifugal
I believe that vacuum casting with an electric melt furnace provides
a more consistent metal and flask temperature at the pour. The
flask is at a known temperature when it is removed form the oven.
The flask will not have enough time to cool before the metal is
poured therefore the temperature of the flask at pour is known. The
thermocouple of the electro melt will give the relative temperature
of the metal when it is poured. Corrections can be made before the
next pour If there is a problem in the casting caused by improper
temperature of the flask and metal.
I don't believe, unless you use a high end centrifugal casting
system, you can obtain the same temperature consistency with
centrifugal casting using a torch to melt the metal as you can with
a vacuum system and electro melt furnace. With a centrifugal system
the flask temperature may cool or be heated by the torch before
pouring the metal. The temperature of the metal heated by a torch
is unknown and not consistent between melts.
Kenneth Ferrell made many good points in his post. He has
experience with both types of casting.
Thats my 2 cents and more,