I have watched a few of those YouTube videos and figured it looked interesting, but the thought that would go through my mind is the cost and time involved for what most ended up with. I would say that most that do it, do it as a hobby and not a money maker.
I have seen a few guys that were casting parts and other useful things. But most was just bricks, ingots and drops and such.
Check out
eBay for the many things that people have cast to sell. The BIG money goes to those that have a special talent at it.
Just some thoughts
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