[Billfred]

In eleven years of FRC, my teams have welded two things:

1) In 2004, 1293 welded up the robot frame. (This was the last season of the "Uh, here's some 2x4 box tubing and some super-fragile drill motors" kitbot before they switched to the sheetmetal JVN/Copioli kitbot in 2005.)
2) In 2014, 4901 welded an axle to two ball intake wings.

Two applications, one of which is obsolete and one we probably could've worked around with more time.

I'd give strong thought to the lathe or mill first. My personal pick list would have the lathe first; the ability to knock out shafts and rollers is universal, since you can plunk some bronze bushings in a piece of hardware store aluminum square tubing and be rolling. I'm sure someone will state the case for the mill.

3D printing seems to be getting more and more common in the pits, but I don't know if it's quite there yet. CD has a couple threads on applications here; know the limitations before you drop big money here.

Hope this helps!