Hey, everyone.
I’m thinking of buying a Velleman K8200, printing some parts for a DIY CNC router and using all K8200’s electronics fot that CNC. I’m planning to engrave wood. Is it possible? Will steppers be able to handle that?
Thank you 
Do you want to reuse the frame too?
Or do you want a router that can handle heavier loads?
Then it would be a better solution to get a more suitable controller/stepper setup.
The steppers are probably strong enough for light CNC work, but you will need to replace the x-y axis (belt drive) with a threaded drive if you plan to do any routing or sideways cutting.
But I think once you get your printer built and running you will not want to take it apart again. If you really don’t need it after that, it would make more sense to sell the working 3D printer and use some of the money to buy new parts for your CNC project.
Depending on your needs there are several reasonable priced CNC router kits
on the market. Maybe have a look at the Openbuilds Ox.