Some folks just want to experiment with melting and casting aluminum, and I think they are not really serious about anything other than making ingots.
There are some who seem to generally only make ingots, and other such things, such as this person:
He has a great time with it, and is a 1.48M subscriber ytuber, but in the end it seems to only be lots of ingots.
A word of caution about melting scrap metal; some alloys are highly toxic, and you should avoid contact with those metal types (I don't have a list).
https://www.youtube.com/@bigstackD/videos
Other hobby folks seem to sort of try to make gold out of lead, metaphorically speaking.
They try to create new magical alloys that are stronger and better than anything invented.
There are what I call the "better mouse trap" burner people, who claim to have a burner design that will do everything including saving the whales. They experiment endlessly with their exotic burners, and never get any significant performance out of them as far as a burner that is useful for melting aluminum or iron efficiently.
There are places to buy approximate aluminum alloy 356, which is what is generally what is used for cast aluminum parts, and the price is not that expensive.
Too often someone makes a multitude of ytube videos showing them playing with fire, and molten metal, and sometimes they almost blow themselves up when they mix molten metal with moisture and/or water.
There are a few proven methods and materials that can be used successfully for foundry work, and materials that will hold up for more than one or two melts.
There are methods that can be used that will give a high probability of successfully making a high-quality engine casting.
It is too bad that there are so many examples on ytube of "how not to melt metal", or "how not to build a foundry".
It took me a while to sort out the valid information from the junk science.
Most of the casting videos on ytube are junk science, or just done for entertainment, and not for serious casting work.
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