CNC controller

[ddmckee54]

What are you guys using for a controller on your CNC's?

The last CNC machine I built ran off TurboCNC so I'm looking to step up to something that's using technology that's at least in this century.

I'm in the process of designing/building a CNC router and I'm not sure which way to go. I'm currently designing around a 48"x24"x6" working volume and planning on using NEMA 23 steppers for the X, Y and Z axis. I'm not planning on, and don't need to run this at blinding speeds, I figure that rapid travels in the 125"-150" per minute range are more than enough.

I have looked at the following:
Mach 3/4
Flashcut
LinuxCNC - I don't have a Linux machine but I'm including it because somebody would say I need to use it.
Acorn Centroid
TinyG
Arduino GRBL

I know each one has advantages and disadvantages. What are you guys' using and why?

Don

 

[ddmckee54]

Just realized that I didn't say what I'd be cutting, I'll be cutting mainly wood and plastic with MAYBE some non-ferrous metals thrown in at greatly reduce feed-rates and DOC. The spindle will either be a Bosch Colt compact router, that I already have, or a Chinese spindle in about the 1KW range.

I would have just edited the thread, but that ability is eluding me at this time. (I just saw the edit button, it was too obvious, that's why I couldn't find it!)

Don

 

[propclock]

I have been very happy with Mach3. I use a Galil ethernet controller with servo's
but and old PC with windows XP(no internet) and a parallel port will give you step and direction signals for your stepper drivers.

 

[Woodster]

I built a 3 Axis Mill/Router using an Arduino Mega256 with CNC shield V3 and Nema 17 steppers. I geared the steppers down 3:1 to give me a bit more torque. I use GrblPanel to control it on a Windows 10 PC. Cheap, Cheerful and Easy. I also set up an Ad-Hoc 4th Axis that uses the X Axis signals for engraving Rings. A little bit of maths to get the right settings for the diameter of the parts and program as a linear part instead of circular.

 

[ddmckee54]

Woodster:

I'd heard that Arduino/GRBL couldn't handle arcs/curves. I'd also heard that the curves needed to be divided into a boat-load of short, but straight, line segments. From your comment I gather that this is true. What software do you use to convert the curves, or do you do it yourself? What are you using your machine for? Have you looked into GRBL for a 32 bit machine, I think it's called "SUPER GRBL"?

The arcs and curves thing was the main reason that I was leaning away from using an Arduino based system.

Don

 

[Woodster]

I design in Solidworks, program in FeatureCam using Emco post processor and use either GRBLpanel or Candle to run the code (PM Me for more info). Arcs are no problem, both controllers support GO2/3 circular interpolation and you'll get even smoother arcs if you use micro steps and gear down the steppers. My GRBL settings are something like 4800 steps per MM, which allows for really smooth arcs. My Rapids suffer a bit, but i can live with that. I'll upload a test conrod photo to show you.

 

[jumps4]

Centroid Acorn Is my choice by far.
I have been in cnc for over 15 years and started with mach3. The mills and plasma/ routers I have built have always worked well but the mach3 lathe was a pain to get threading properly. Mach3 was at it's end and could not be fixed so new owners made mach4. I haven't tried 4 . Mach3/4 has always been a hobby company trying to improve, Centroid is a commercial company building and converting commercial equipment that now offers a hobby board. Big difference.
my newest lathe is amazing, easy and with in forum tech support I'll never go back. windows 10 64 bit Intercon cam software built right in.
Steve
My Lathe: https://centroidcncforum.com/viewtopic.php?f=57&t=3068

 

[Mark Duquette]

I use LinuxCNC which is free and community supported. With LCNC you can control simple steppers to state of the art servos. There is a stepper leaning curve but well worth the effort.

Note: PathPilot is an extension of LCNC.

 

[lemelman]

Fusion 360 can generate G-code in many different dialects, including Mach3/4. It's also free for non commercial use. It uses the same CAM engine as Solidworks - the expensive one.

 

[Bryanbdp]

I would suggest mach4 which works with ethernet and latest windows. Gecko drivers are very highly regarded and not that expensive, don't buy more driver than you need... smoothstepper a good way to go. Also, there are some affordable "closed loop" steppers that can detect missed steps...

 

[Leonardo]

Hi all! Just would like to share with you my experiences.
I am producing a desktop but quite robust CNC milling machine based on the structure of a previous development.

For this project I am using an Arduino UNO R3 board with GRBL V1.1 embeded firmware. I have mounted the Arduino on my own I/O board achieving a very good and reliable 3 axes controller.
GRBL is really great and can manage G2 y G3 codes (arcs an helical motions) without any problem. Perhaps the confusion comes from what they say in their website "Multiple full circle arcs with G2 and G3 arcs with a P word is not supported", but they are talking about "full circle". Only real limitation is that GRBL do not support canned cycles like G82, G83, etc. but you can make your own macros to solve this problem.
What I LOVE of GRBL (and Arduino) is the freedom of this open source platforms. Here is a link to this amazing development's site: https://github.com/gnea/grbl/wiki

Regarding the GUIs, I tested many of them but I think that be best one is Grbl Panel. It runs flawlessly every time for hours. Never had a single problem.
There is another interesting GUI that is an app for Android called Grbl Controller. It is nice but I detected a couple bugs and have not tested it enough to give you a final opinion yet.

Regarding post-processors, I have "tuned" post for VisualMill, 3DCut and Aspire to work with GRBL.

I am pasting here a couple pictures to show you my machine and what you can do with it and GRBL.

Have a nice weekend!
Leonardo

 

[Pauldg]

What are you guys using for a controller on your CNC's?

I have looked at the following:
Mach 3/4
Flashcut
LinuxCNC - I don't have a Linux machine but I'm including it because somebody would say I need to use it.
Acorn Centroid
TinyG
Arduino GRBL

I know each one has advantages and disadvantages. What are you guys' using and why?

Don

I'd heard that Arduino/GRBL couldn't handle arcs/curves. I'd also heard that the curves needed to be divided into a boat-load of short, but straight, line segments.

Hi Arduino uses 8 bits logic and emulates 16 bits arithmetic. This all works really well but for high accuracy work I would suggest you use a 32 bits based CNC controller.
GRBL does apply bezier lines/or AMASS to curves. Basically this means that the firmware increases the accuracy of the steps (increased number of tiny steps) when there are small or sharp curves so you don't see a staircase. It works really well.
Good luck,
Paul

 

[Leonardo]

By the way, I remembered that I have this controller in my to-do list but I did not tried it yet.
It looks very interesting because you have all you need in a handy enclosure and you can add a pendant too.
Take a look at it: https://www.ebay.es/i/352592397929?ul_noapp=true
There are options for 4 and five axes too:
https://www.ebay.es/i/352713998169?ul_noapp=true

https://www.ebay.es/itm/Upgrade-DDCS-V3-1-4-Axis-Motion-Controller-Offline-500KHz-CNC-Standalone-Control/113821406686?_trkparms=aid=555018&algo=PL.SIM&ao=2&asc=20160908110712&meid=87e3c95e1c06457b917d2be1eb58b36c&pid=100677&rk=6&rkt=8&sd=173652933171&itm=113821406686&pmt=1&noa=0&pg=2385738&_trksid=p2385738.c100677.m4598

 

[e.picler]

Hi Don!
Take a look at this one. I'm using it on my tabletop milling machine, (you do not need a computer, it is a stand-alone controller). Workes very well
https://www.ebay.com/itm/Digital-Dream-4-Axis-CNC-Standalone-Offline-Motion-Controlle-DDCS4-V3-1-DDCSV3-1-/273691306050

Also, take a look at this one
4 Axis
https://www.ebay.com/itm/4-axis-CNC-Controller-50KHZ-CNC-4-Axis-SMC4-4-16A16B-offline-CNC-controller-/282016564542?_ul=BR

5Axis this one is more complete
https://www.ebay.de/itm/500KHz-CNC-5-Axis-Motion-Controller-Offline-CNC-Controller-Mach3-USB-Screen-7-/223543085433

Edi

 

[accelo]

I looked at the controller you posted the link to.
How is the documentation? Is it in the bad English I am used to on China products?
Explaining CNC controllers requires good English and support.
Is the only support feedback on the Ebay site?
That's the reason I haven't purchase one.
I don't need another "CNC" headache!

 

[ddmckee54]

Leonardo:

That's an impressive looking machine, what is its' work volume?

If I'm understanding this correctly, GRBL will do arcs and curves, but it doesn't like complete circles? Years ago when I was just getting started in CNC I was using a DXF to G-Code converter that had similar issues, I had to be sure I split every circle into multiple parts.

 

[e.picler]

Hi Don!
I understand your comment I agree.
Take a look at the manual to know if it has understandable English for you.
http://www.ddcnc.com/upload/product/DS_DDCSV3.1.pdf
When I needed help on the configuration of the 4th Axis they gave prompt good support.

And here the manual from the other brand
https://www.lollette.com/support/pdf/CNC/SMC5-5.pdf

I'm not a native English language speaker and it worked for me.

Edi

 

[Leonardo]

Hi Don, thank you!
The travels are as follow: X = 350 mm, Y = 250 mm, Z = 100 mm. Aluminum cast structure.

Unfortunately I am not very good at G coding, far from that. I always use CAM software so I let it deal with that "details".
G2 and G3 might be more important working in 2D and 2.5 D but I almost always work in 3D. Analyzing a 3D G code files I always find zillions of G1 movements and very few of G2/G3 so I really do not care very much about that. This is my own case but cannot speak for others because my knowledge is not enough to go so fine on this matter.

I would process a CAD file with some arcs and circles to see what happen... I will let you know the results.

 

[Leonardo]

Don, it took me some days to have the time to make these test but here you are:
I did two jobs. The first one with tabs in both profiles and the second with engage ramps.
I did nothing special just post processing the sketch using Aspire software. The machine performed the jobs perfectly.
As you can see, the helix engage was cut in small vectors and the circle was cut in four quarters but you cannot see/detect any stop in the actual machine movement.
Hope this help a bit!
Leonardo

 

[kvom]

I use LinuxCNC which is free and community supported. With LCNC you can control simple steppers to state of the art servos. There is a stepper leaning curve but well worth the effort.

Note: PathPilot is an extension of LCNC.

I replaced Mach3 with PathPilot on my mill. Very happy with it.