Here’s the thread in the forum about running a version of GRBL on a RAMPS board and being able to utilize dual endstops.
https://www.v1engineering.com/forum/topic/grbl-running-on-ramps/
Not real familiar with this stuff but I would think that you should be able to make it work on your MKS Gen L board.
Thanks for the link to that thread! I had just found the grbl-MEGA-5X github and was wondering what all I would have to do to make it compatible with the MPCNC with dual endstops.
Am I understanding correctly that I have to have an external PC/Laptop/Raspberry Pi for machine control? Can I use the LCD/SD Card at all?
That is correct. CNC.js on a v1pi or even running as a desktoo application works well with it though.
First thank you for putting this CNC together as open source.
I was thinking for a while building a CNC but being a hobby could not get one for my small budget. This one was able too build it for under $200 but had to cut some corners 
As I already have a 3D printer which uses RAMPS and marlin FW decided to go with this hardware.
Wired the current Y axis (the one moving on the roller blades) using dual stepper drivers and wired the Z motors in parallel. Currently have no end-stops and was annoyed by the question marks on the LCD display so I start learning the Marlin Firmware code.
Currently I am waiting for some cheap mill bits to start cutting something.
I can build small gcode either by hand or generate it using software and quickly found some limitations of the firmware. So I am currently building a custom CNC menu into the firmware and I am looking for feedback.
The CNC menu appears immediately before the existing MOTION menu on the LCD and currently planning to implement the following structure:
RESET ALL AXES:
allows for setting the HOME position (X=0, Y=0, Z=0)
unfortunately in Marlin G92 X0 Y0 Z0 does not set machine coordinate but offsets so had some trouble getting this working correctly.
PROBE:
MILLING:
soon realized that if I want to use metallic tape I need a good surface to mount it to, so I built this menu to be able to run simple milling procedures.
In order to have a good surface I decided to implement algorithms that generate gcode in memory and drives directly from the LCD. (no SD card necessary)
Added operations for milling a corner of the board flat so I can stick the tape. This can be used for changing tools later one (I still have to figure this thing out)
Also added one more operation for drilling at the current position in order to be able to screw the board if needed.
The last three menu Items are currently there for manually set each axis origin separately.
Please give me any feedback on this menu and if you would like to see something else inside.
If @Ryan agrees I can work with him on getting these changes applied to his GitHub for somebody else to test them. I only have limited time and a single machine to test with so any help is appreciated.
The 3D printing got to the point where everything is so simple, on the CNC world no so much, and my plan is to bring this one step closer to pressing one button and start the milling 
PS: @chaotix here was mentioning the SCAN function that finds the edges of the print. would be interested to hear more about this feature as I think would be useful to implement too.
You can keep your own branch current with my firmware on github. That is easier than me trying to keep track of menu edits as the LCD stuff changes all the time.
Hi! I’m trying to do a pcb milling machine but I don’t know if I have to use arduino CNC shield or Ramps. I know that Ramps are mostly used to build 3d printers and that it uses Marlin firmware but the thing that I don’t know is if Marlin can be switched to be used for CNC or if it’s better to use CNC shield for arduino with GRBL.
Thanks!
Oh my… Yes, yes, yes, and I believe yes.
With the current state of affairs, Marlin is getting really good at being a CNC firmware. GRBL is still probably better is some ways due to its better feedback loop, but there are ways to work around all of it. Around here, the bulk of experience is with Marlin, but there is also a good working base of GRBL users. That being said, there is a small, but enthusiastic group (2-3?) of folks tinkering with LinuxCNC (no firmware, your Linux workstation is your controller).
If you go with Marlin, spring for a bonafide Rambo board (Ryan sells them at about the best price you’ll find). The RAMPs boards you find these days are Chinesium clones that tend to release their magic smoke easily, and the Mega boards they are often paired with come from the same factories. The Rambos have good protections (easily replaceable fuses, etc), and you may end up spending less on the one expensive board than on a number of cheaper boards. The MKS and SKR (I may have my alphabet soup wrong) boards are also being used, along with the Archim boards, but some configurations are really bleeding edge, and will require a lot of firmware tweaking and flashing.
GRBL has some interesting things happening, including a fork with 5+ axis control, allowing for dual endstops along with the (currently) better laser handling (vs. Marlin).
Ultimately, if you’re milling PCBs, the most important thing to do is to keep your build as small as you can and either keep your Z size really short, or always put your workpiece on a platform of some sort to effectively reduce the Z height to near zero. This is all to maintain rigidity and increase your precision. Large builds and extending your Z axis make for floppy spindles.
I’ve probably “plugged” Marlin more than GRBL, but that’s because I know it better. I know GRBL enough to know it’s a great firmware, and that there is no reason not to use it. Personally, I think they are both fine for our purposes, and you should go with what you are most comfortable with.
Oh, and welcome to the circus! 
Thanks!!! I know what you mean… but there’s something GRBL has that Marlin doesn’t or viceversa
Right now (things change fast), Marlin has these advantages:
The advantages of grbl:
grbl has one main software version, and it basically only works on the arduino uno breakout board. There are modifies copies of grbl for some other boards (like the 5 axis rambo or ramps forks). It is possible to use these, but they are definitely not as “stable” as the main grbl software.
A worthy mention is the Grbl_esp32, which is a modified copy of grbl meant to work with the ESP32 boards. I am personally a fan of them, but I don’t have much experience. There is an MPCNC board for it. It will definitely be harder than the preflashed rambo from Ryan.
I am new. This is my first post. I am almost done printing my MPCNC Primo but I want to run it on GRBL as I am most familiar with the CAM software for laser and cnc milling. I am coming from a generic 3080.
I went with the 23.5mm 3/4 EMT conduit as I already have some.
Only problem is I am someone who needs that step by step guide and I can’t find it with a lot of googling and YouTubing. I’m not a tech person just a mechanically inclined person.
I really want to avoid marlin. Would someone volunteer their sanity to help me.
Need a hardware guide and step by step on flashing firmware I guess.
Also to note I would like dual endstops which I guess I would need to sacrifice for Grbl but I have an idea on how to deal with that and manually square the machine.
You will likely get more responses to your question if you create a new topic rather than appending it to a five-year-old topic.
As for GRBL, the starting point is the selection of the control board. To me, there seems to be many forks of GRBL, each built around a control board or a class of control boards. Some of these forks seem to be well supported, while others seem almost experimental with limited support. The most mature version (for the MPCNC) is built around the CNC Shield, but with support for only four drivers, you definitely won’t get dual endstop support with this control board.
I did run across this topic some time back where someone implemented a version of GRBL with dual end stops for the Rambo board, but I don’t know how much support there is for that version.
I am going to stick to what you guys offer and just adapt. Relearn a little it can’t kill me I’ll get it built and running and use estlcam. As for a laser I’ll have to work that out too. I’d rather have a working machine than a bunch of parts that can’t move cause I can’t figure out how to use 5 steppers on a 3 stepper board
If you really want GRBL, there are active users on the forum that use CNC Shields, so I’m sure you can get it running. As for using 5 steppers on a 3-stepper board, you would need to wire them serially. Here is one wiring diagram. I don’t think V1 sells serial harnesses anymore, so you would need to wire it yourself.
As for laser on Marlin, the V1 maintained firmware for the Rambo and SKR Pro boards have laser support enabled. For other boards, you would need to make some simple changes before compiling. I run a laser on my Rambo board all the time.
If you really want to do that I would recommend this, 6 Pack Universal CNC Controller from Bart Dring on Tindie I was told the board is in the works to get into a production somewhere else so hopefully they will be available soon.
I will say the easiest way by far and the most supported is Marlin around here. Once you get it working, though, you should not have to touch it again.
You can run a second shield. Self squaring would still be out of question but you would be able to run a pair of drivers and steppers per axis on those UNO boards.
I always prefer marlin for milling
but grbl also not bad for .
I am going to go GRBL I am finally wrapping my head around this. Seems like driving 5 motors from a 3 axis board isn’t an issue in series wiring. I have been enlightened so THANK YOU GUYS! So my next question.
I might make some gasp is horror but for some reason flashing the firmware and customizing it and getting it to work is making me nervous. My concerns are all firmware related. Can I just use this board from a 3018 Machine?
My reluctance on using an Arduino and CNC shield is again the issue of firmware and how to get that to interact with my hardware
Since I have the Laser from my 3018 I don’t need to buy that. I like controlling the machine from my laptop. I plan to control my spindle with a relay. I don’t plan to 3D print with it as I can’t imagine what I would want to print that would need this type of large format. I realize this likely would need a major upgrade if I ever wanted to do 4 axis. But the board cost is minimal.
Main question is do you thing I am going to nuke the 3018 board running 5 stepper motors on it?
Just get the Arduino and CNC shield. It’s actually pretty simple.
You probably could run the Primo off of your 3018 board with the motors in series, but the drivers are probably cheapo A4988s that will not manage 1A of current, nor aill the board be comfortable with the power demands of 5 motors. I would say that a CNC shield with at least 1.5A capable drivers is going to be less likely to give you headaches.
If you are not comfortable with flashing firmware though, the bast support that you will find around here will be with the pre configured firmware on the marlinbuilder releases page. I have used GRBL and Marlin, and from a user perspective, they aren’t much different. The computer end is very much similar. Having pre-configured firmware binaries makes it pretty easy.
If you do use your existing board, you will need to make up series wiring harnesses, and reconfigure steps/mm to 100, 100, 400. It is probably 400, 400, 400 (My 3018 is) probably you also want to adjust the driver current as well. Look up the specs for your drivers, since there are different ways that the current might be set, and what the reference voltages may be.
Uno + shield is more flexible in terms of driver usage.
The 3018 (most probably) might not be able to handle the 5 motors.
In the motor series connection I Don’t believe the problem is the current but the Lower voltage across the motors coils that will translate in more noisy operation and torque losses.
Flashing Grbl into an Uno is a no brainer with XLoader.
