A bunch of mine have already been mentioned, but here’s a few more.
Demolition Ranch, it’s essentially a gun channel, but even if you’re not that knowledgeable about guns, even if you don’t like them, a lot of time is devoted to ‘what happens if I shoot this gun at that object’.
OffTheRanch, same person, but this one focuses on projects around his home. He’s just kinda fun to watch, but this channel and his other one VetRanch (he’s a vet), while entertaining, are mostly for the fanboys.
ElectroBoom was already mentioned, so here’s BigCliveDotCom, AvE and ThisOldTony.
Big Clive spends his time tearing apart (or ‘taking to bits’) all kinds of electronics, mostly cheap stuff from China, bought on Ebay. AvE, he spends most of his time taking apart tools. What makes him really interesting is that for as much as he might seem like a bumbling Canadian Ape as he tears things apart with a bit too much enthusiasm, he really knows what he’s talking about. This Old Tony is a machinist. His shows are good, but he draws me in with his editing and odd banter. And along with machinists, don’t forget Abom79. Some of his videos are set in his home shop, the rest are at work where he runs huge (10-15 feet and a foot wide) chunks of metal on a lathe.
If you like welding, there’s WeldingTipsAndTricks, Weld(dot)com and KevinCaron (and yes, I left a ‘big’ one off the list on purpose).
And then we have a selection of random ones.
WaterJetChannel. They cut random objects with a waterjet. Mitchell will probably taste test it.
SmarterEveryDay and SmarterEveryDay2.
PrankstersInLove, a husband and wife duo that prank each other. Really good pranks that. Like, way overboard. They shaved each other’s eyebrows, hair dye or nair in shampoo bottles, I think they’ve both been glued to the toilet etc.
Vsauce, similar (kinda) to SmarterEveryDay
Someone mentioned Tested upthread, VSauce and Adam Savage have done some collaborations. It’s interesting watching the two of them working together. It’s basically Vsauce working things out in his head while Adam can build just about anything.
Lastly, my go to show for car repair is South Main Auto. However, plenty of people also like ScannerDanner, EricTheCarGuy, Scotty Kilmer or SchrodingersBox.