Hello All, I have admired this community for sometime and I am finally able to join. I am building my first MPCNC and was looking for helpful advice. I have about half of my parts printed in PETG and have verified my tolerances. X is perfect, Y is -.001 and Z is +.001 on 20mm calibration cube. I have ordered .065 304 SS tubing. I would like to use this machine to its maximum capacity and will be doing wood, plastic and aluminum milling. using a drag knife for specialty flooring on foam flooring for my buisness and 3d printing for my buisness as well. I have alot of customers with large build volume but less than 1in Z axis needed. What would the best board for me to get? also how hard would putting auto bed leveling on the machine as well? I am new so I apologize for any “obvious” questions I may have but I will be a willing participant in the forums and try to learn as much as possible. I love learning new things and this is definitely a new area I want to learn.
3d printing is possible but it’s not the most effective way to do it. Do you have some unusual 3d printing needs?
As for the best board, I think the Rambo is the best choice if you are not too constrained on budget and you want to consider future upgrades. Dual endstops is not the best starting point but Rambo will let you go that way later if you decide you need it.
Auto bed leveling is going to need a method to perform Z probing, but apart from that it’s enabling and learning Marlin features, which are not always the most simple but the functionality exists. The harder part will be setting up the Z probe but it’s also very doable.
I definitely have some unusual pieces to print. ranging from 12-20 inch long. So that is why I am interested. Otherwise my MK3S is a marvel and will be my workhorse on 90% of printing. I understand the basic premise of the auto bed leveling, it is part of the calibration on my printer. I was going to use a BL touch but I am here to learn and look for advice. I need to learn a lot of the firmware but I am more then happy to put the time in.
Nothing wrong with BLTouch, I have one on my main printer, but you will have to watch for clearance. On a printer the probe only needs to retract slightly above the nozzle, but for carving you need to clear the maximum carving depth. That would mean you might need to go the route of those old school servo-based stow/deploy. But even so, that’s got support built in to Marlin too, so if you’re at least moderately handy you should be able to get it working.
I’m eager to see what you’ll be making!
nothing fancy on the weird sized parts, just dash panels or clusters for boats. Lots of no longer available parts
Likely the pieces you are going to be working with won’t require the extra accuracy that the bed leveling gives you. Remember you are no longer constrained by the first print layer! 
If you decide you need it then plan to work on developing something in the future, for now just use the tried and true methods, such as a surfacing run on the spoil board. You might also find that milling a piece could work when your first thought is to print it…
Appreciate that Bill, on the 2-d style dashes that is a great alternative for sure to be honest I come from more of the additive side then subtractive but planning on working on that once I get this girl running. I will probably just buy the kit with the Rambo board just to cover the bases.
It can also be worthwhile for 2.5D cuts (better known as carves). Where it doesn’t make sense is when your design has bridges, it’s tough to cut under the material without more like 5 axis.