Size recommendation for MPCNC and 3d printer

I want my MPCNC to do both but I haven’t seen much info on build recommendations since I’d also like to be able to do some light aluminum milling as well. If someone could point me in the direction some build recommendations or something that’d be greatly appreciated.

Additionally I was hoping taking some clarification on the workflow for both the 3D printing side and the CNC side. I have used other 3D printers and other things he’s but never one that was combined. All of the CNC is that I’ve used primarily used grbl and I’m not sure what would be needed to allow the g code from my cam software to work with the Marlin firmware. If a can point me in the direction of a post processor or whatever tool I should be using that’d be greatly appreciated

If what I’ve said above is unclear please let me know and I can try and explain again.

Thanks in advance to anyone who offers advise, suggestions or tips. Also for any spelling or grammar mistakes. I’m writing this on a phone and can’t easily review my entire message.

Marlin is very similar to grbl, it’s motion software is based on grbl, but there are some differences. There are two common CAM software tools used, the postprocessor for AutoCAD fusion 360, and estlcam. There are guides and forum posts here:

There are also links there for some slic3r settings.

On the size, I probably shouldn’t advise, because I don’t use mine for printing, but you probably want a build area close to 200x200x150mm for a great printing experience, but larger to make fun CNC projects. If you are already an experienced 3D printerer, then a larger build area is OK. That’s completely based on my impressions and what I’ve read here. @vicious1 will probably have better advice.

My CNC build area is 2’x3’ and it’s awesome, but not perfect. I have enough printing experience that I bet I could do some good printing in the corner on a 200x200mm bed. Never tried it though.

It’s advisable to not use them for printing and milling on the same machine. Unless you can make the corner supports adjustable, you’ll not have good milling experiences. You want it as short as possible for milling, I think mine is about 4 inches high with a 3/4" piece of mdf raising the cut piece up from the base. I’ve done aluminum, but it wasn’t anything that needed fit into something else, so not sure how accurate it was. It looks good, so that’s all I cared about. You wouldn’t be able to print anything tall with this arrangement though. I suppose you could print out a full scale Capt. America shield, which would be freaking awesome to see. Bonus points for using Red, White, and Blue filament! If you make it taller for printing, then you lose side to side rigidity for milling.