Lantz no one actually uses water as a coolant during metalworking, you use heat-treating oil.
You actually could, but shit's old style.
Let me reword myself. Using water as a coolant is shit and makes the item brittle as fuck, but you can totally do it, your result is just going to be awful.
Satoshi is supposedly this master smith who's infinity years old, yet he doesn't even know this.
I'm basically pointing out that if Lantz wants to put all these jobs like smith and doctor on his SI's profile, he should do the most basic of basic research. I think I've used a day's worth of time researching Kalaripayattu just for a future fic of mine, so Lantz could at least go watch Man At Arms or something like that to at least get a feel of what his character is doing.