the high rpm is a demand... to reach an acceptable processing speed..
you going to use v bits, or rather engraving bits with very small tip.. likely 0.2 mm or less
and clean areas with 1/8 bit...
there are small spindles with 60 000 rpm..
you can use 60 deg engraving bits to making sharp corners...
since tools has so small working diameter the forces are very low..
300w CNC Milling Spindle W/ ER8 Chuck (KL-300) | Automation Technology Inc
please note for this spindle you need inverter too..
however it worth to invest, if you plan to make press plates ...
with a normal ballscrew from ebay you cann get 0.01-0.02 mm backlash.. that's already sufficient.. so any machie you go, these you can consider..
some video shows what speed you can reach with high rpm motors..
this video shows toolsteel engraved..
https://www.youtube.com/watch?v=0cugaYJzeIg
I forget to mentioning, you can find some info about etching copper.. while it is not diifcult, however you cnat achive the necessary depth in one pass
due acid will ""undercut"" your stuff.. and thin lines ""separating"" from plate..
heres one company you could start... there are more..
https://www.graphicchemical.com/shop...asp?id=38&cat=