Turn Wright Machine Works
An old-school job shop run by a machinist/welder who knows his business, with every machine and process in the shop save one (the Plasma cutter) totally manual: the lathes, milling machines, drill press, all of it. Best of all, he's willing to teach the how and why without holding anything back smbstressfest
One of the best instrument setup/repair channels I've found so far
FWIW I'm not a big fan of davey4557 at all. To me, he comes off as an overly opinionated drunk who's OK with setups but I wouldn't let him within a mile of anything that needed serious structural repair. Compare the way he did the '64 Martin neck reset with somebody like Brian Galloup
or the general level of his workmanship on fretwork with somebody like Freddy's Frets
Check 'em all out and judge for yourself. Just my 2¢ worth....