"Hobby machinist - Is it worth starting?"
.............Yes it is, if that's what you REALLY want to do. That is, if you REALLY know that's what you want to do, and would enjoy it. If you're not sure, or if you have an affliction of sitting in front of the boob toob, then don't bother. You'll regret the money you spent finding out, and you'll never get it back. A pittance of what you spent is what you'll get back.
I'd suggest that if you're asking then you probably do not have the burn. There are people who were machinist's, or worked in a machine shop simply as a means to get a paycheck. It was a job and nothing else. Of course there was the odd few who possibly used their knowledge at home as a hobby making what they wanted to make, for their own enjoyment.
If you think you'd make the occasional size die, or would be able to make the odd "do-dad" for a gun or accessory, or a part for the washing machine, then forget it. Save your money and pay someone else who already has the equipment to make it. I don't want to be negative about it because for myself I'd rather be out in the shop making something then doing almost anything else. The only time you'd find me in the house during the day is if I was on my deathbed. I get all fidgety if I'm away from my stuff for too long.
Quite often I've spent more money making something then I'd have spent buying it someplace! Must be genetic because my 2 younger brothers are about the same. Not as bad as me, but similar. I constantly marvel at the people I see at Lowes or Home Depot looking at some blow molded 4'x4' outdoor closet to store their shovel and hoe, that costs $400. Or a 8' x 12' shed made out of 1x2's and plywood, 2 squares of shingles and it's priced at $2600! Doesn't matter what it is. I'd rather be making or building something then anything else I can think of.
The thing is, without the 'Burn' (for lack of a better term) you may end up resenting every penny you have to spend for a piece of tooling. Heck, I had spent over $3000 in tooling for my vertical knee mill before I'd ever even bought the mill. I simply KNEW that I was eventually going to get a milling machine, and I eventually did.
I'm so bad I own tools I don't even know I have.
Swage dies, and core moulds for the swage dies .............
Bullet moulds, this one for a 12 ga shotgun slug
Rear sight for a an AMT semi auto 30 Mi carbine pistol, or a action nut to remove Krag actions
New bolt knob for an old Winchester 22RF semi auto rifle, die holder to use in the lathe's tailstock
Bore out a wallered out water pump pully from an old Waukesha diesel, make a new sleeve, for it and press it in, then bore to fit the shaft. Make a dealie bob to drill HP's in loaded 45 ACP's.
You really need to figure out if buying a lathe and then spending the time and money in tooling it up for what you're wanting to do is what you REALLY want to do. If you enjoy making things then it might work out. Just don't show your wife what you've just spent 10 hours slaving over as it can be deflating. She'll probably glance at it and say, "That's nice, did you carry out the trash like I asked you to?"
............Buckshot