Jeremy Fielding is a great engineer/hobby machinist and has built some very impressive things. His industrial robot arm is very impressive and I'm hoping he gets it to doing something productive soon. He's also a Solidworks user and has some really helpful Solidworks videos. I'm hoping he makes some more of those because every video where he's designing something, I feel like I learn something new.
Stuff Made Here is also great. All design/builds and he actually gets in to the engineering behind everything he does. Very entertaining too.
Might be out of your normal wheelhouse, but
BPS.space does some fantastic design and engineering of amateur rocketry. Very 3D printer heavy, but great technical content.
--Self promotion alert--
I'm not anywhere close to in the category of content creators mentioned in this thread, but I also restore tools, do some machine work, and use Solidworks - my YT channel isn't that filled out yet but hoping to have some videos up on design/build using Solidworks as time permits.