Hi,
machining metals, even soft metals like aluminum requires a VERY rigid machine, especially if you want to hold tight tolerances and good finish.
May I suggest you look at one of the many drill-mills out there. This is an example:
https://rongfu.com/mill-drill-machin...-machine-rf45/
Note that this has a rectangular column, and is preferred over a round column being somewhat more rigid. There are many companies making machines of this type, and they are pretty good value for
money, and very often come onto the second hand market, where you could make a very good buy.
This machine is not CNC, but you could convert it. There are threads on this forum about people who have done just that. Not cheap, or easy, but satisfying. Note also that this is not a big machine,
you would not expect to make big parts. The machine is quite rigid and does a good job is aluminum, and with care and patience does a fair job in steel. Steel is very tough to machine and takes
a way more (x5) rigid machine than even aluminum.
A machine such as this would absorb you entire budget or more just to buy the basic machine.....without considering a CNC conversion. I have posted this so you can see just the sort of machine rigidity
that is required to mill aluminum with good accuracy and finish. Machines like this are
adequate....not over the top, or even very good, just
adequate!.
Craig