Some other real good advice.
Just like we have all been told "don't put all your egg's in one basket".
I say the same goes for jobs, especially nowadays, since we all seem to last a very short time at jobs. I've hired in and quit many times. And besides you can stay at one job for years and then the day comes and they go outa business, then your in the cold. What I'm saying is learn a variety of jobs, learn the operating, and some of the mechanics, like the guy above said they can't find people to even learn it, so you really don't need to learn a bunch to do the simple average wrench twisting, what you do need is the apptitude for it, that alone will cover your butt, any shop will show you what you need to do most of the time anyway especially if they don't have to pay a top wage. Its way harder to learn to operate heavy equipment than to mechanic, mechanic is a knowledge type job that does require some skill level, but operating and welding are a skill level job that requires lots of practice and experience to do.
Then there are other jobs like machinist, electrician, plumber, carpentry etc.
If you learn all them you will always have a job, but again apptitude.
One of the nice jobs would be a electrial controller, meaning your monitering all the electrical system grid etc. it would be a sit on your rear and read the newspaper type of work, or even sewer or water moniter, and they usually get some real good pay and benifits as well. The day you smash your hand wrenching, and take a good soaking of oil, or a nice burn or cut, you will remember what I said here. By far operating is the most satisfying job, cause you can someday tell your grand kids, hey I build that road or that whole area where all those houses sit.