Looks like @raykholo is off to a great start! His new Cohesion boards are for CNCs, 3D printers, and Laser cutters. Did I mention they run Smoothieware? 
http://cohesion3d.com/ – I’m in no way affiliated with the project, just friendly with a lot of the users of LaserWeb, and other developers here in the printing community.
Originally shared by Ray Kholodovsky (Cohesion3D)
This is half.
This is the board I used for my smoothieware transition. https://3dprinterchat.com/2016/10/smoothiefy-your-3d-printer/
6 axis. OK
Limited to Pololu - A4988 (max 1A, max 36V => no 48V is bad)
Update: you can use 6 breakout boards for external stepper drivers boxes.
NO Ability for closed loop servo operation with E-Stop if a position just can’t be reached or held.
NO Hardware E-Stop input that still works if the software hangs. (some external “kill” button…sounds like the opposite of an E-Stop.)
NO PWM output for a spindle.
NO More Opto Isolated inputs and outputs then just 2x the number of axis?
In fact, just 6 end-stop inputs for 6 axis.
Ethernet expansion board but not for feeding it commands from the Machine Control Program but for some kind of web-interface
NO RS485
NO MACH3 driver.
What a beast!
@Marcus_Wolschon the board is not limited to just the A4988 - you can use any of the polulu compatible boards including the trinamic TMC2100.
There is a port for controlling servo motors - but I’m not sure what you want / need.
The software (Smoothieware) has a very good watchdog timer, so any time it hangs, it automatically reboots. Eseentially, the kill button always works.
There are two PWM outputs connected through large MOSFETs.
Basically 6 end stops - one each for XYZ Min and max.
Ethernet expansion board provides a web interface that can be used to feed commands. You can also map the IP port in Pronterface and send commands directly through that.
I’m not affiliated with the board or @raykholo , just a very happy early tester of the board.
6 end stops is a bit underspeced for 6 axis (X+Y+Z linear axis pus A+B+C rotational axis on a CNC while PWM controls the spindle).
I’m not very keen on trusting software to hard stop all movement (not just kill power) before someone looses an arm.
How do I feed it commands from MACH3 (usually running on a touch screen attached to the machine with a jogging attachment) or EMC2 or another machine control software?
@Marcus_Wolschon I use this board for a dual extruder 3d printer - so that’s 5 axes, and just use three end stops. Don’t have much experience with other CNC machines, so not sure why I would need more.
There is a reset button too that would kill power on the entire board - and you can probably extend it to a larger kill button.
If MACH3 can send gcode over USB, you should be able to use this board easily. It creates a COM port on windows.
I suggest you look at http://smoothieware.org and see what all is possible using this board. http://smoothieware.org
@Dushyant_Ahuja You often want 3 rotational axis in addition to 3 linear axis to attack the surface from all possible angles in milling.
@Marcus_Wolschon most professional machines are only 5 axis machines. Adding a 6th provides very few benefits. Do you even know of a hobby level machine with 6-axis controls?
Additionally, there’s no need for Mach 3 because the board is controlling stepper timings, etc. All you need is a gcode sender. CAM tools don’t need all of the flow controls, etc that a full implementation of the gcode standard needs.
+ThantiK my large one has. Mist cooling too. Even with 5 axis you’d want an end stop at both sides of every axis to home (if not have home + end switch separately to slow down after reaching one of them but before hitting the other ). So 6 inputs is a limitation.
You also need a height Probe input after all.
If the software on the board does the machine control, how do I jog, attach my jog paddle and how do I need to rewrite my G-code that relies on storing 10x10 Probe coordinates in registers (for milling PCBs)? Rewiring the entire machine to switch from 5\6 axis work in wax to engraving PCBs to 4 axis in wood is not an option. I think this board is very limited for milling machines.
Keeping controller board for timing, hard wired Emergency Stop and lots of I/O separate from the machine control software and PC is a good idea.
@Marcus_Wolschon this is not a professional control board. Your large machine isn’t the target for this board.
It’s a Chinese YOOCNC 600x400 hobby machine that I modified with parts I made on the machine itself and had new electronics and proper grounding added. It’s “large” because the other one is a 400x300 that can be transported to events. By professional standards it’s a toy.
