Here, I‘m looking at comparing the manufacturing costs of the same material and size, using stamping vs casting.
simply put, stamping you'll buy the material in sheets and just run a press to stamp out parts. to cast the pieces yourself you'd need to heat up the copper up and then cast it [in molds] which do you think would be cheaper? just rolling out parts on a stamp machine or heating the copper up and pouring it into molds?
What kind of shape is this copper part that you are considering both stamping and casting? The casting would have to be pretty thick, while stamping is for thin parts typically. You are comparing apples and oranges and makes no sense at this time without describing what part you are trying to produce. Need more info. The two technologies you describe are far apart on what they can produce.
