dear shyam, the real issue is form fill. a company i occasionally
used to build sterling models for required a wall thickness that
reached or approached .5 mm in order to maintain low price points.
in order to fill thinner wax sections a number of factors can
increase your success rate.
-use a centrifugal casting machine(increasing the acceleration will
improve fill)
-increase flask temp. (i normally cast @900 F will increase to 1000
F depending on type of metal and more delicate pieces such as
filligree.
-superheat metal
-select the appropriate alloy for the job some metals/alloys fill
easier than others.
keep in mind that many of these solutions also may have negative
consequences, for example super heating your metal may improve form
fill but cause porosity problems.
matt powell