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Author Topic: Mach 3 or 4 Controller  (Read 815 times)

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Mach 3 or 4 Controller
« on: September 20, 2019, 11:38:09 AM »

I am building a new CNC machine and have purchased all the hardware.
I have 3 phase closed loop steppers and have also purchased a PlanetCNC controller but have now decided to go down the Mach route.

My Y axis has two ball screws and two steppers so I want to some how synchronize both or have separate main and slave outputs and also be able to drive each in turn automatically when homing. Which should also ensure my X axis is square.

The advice I am looking for is what is the best or most suitable controller for Mach4? As a newbie to this and starting out, I think I may as well go down the Mach 4 route over Mach3. I do not want to spend to much on the controller, maybe up to £200 at a push but around 130 - 150 would suit my budget better.

The CNC is a simple 3 axis machine with two drives for the Y axis.
Eventually I would like to also be able to control a VFD spindle and maybe a 4th axis (Rotation / Chuck).

I also like the idea of a controller that does as much motion control on-board as possible (FPGA, ARM etc) so as to offload as much as possible from the PC.

Any ideas or suggestions would be really helpful.

Thanks in advance


Re: Mach 3 or 4 Controller
« Reply #1 on: September 20, 2019, 03:19:37 PM »
my recommendation is Mach4. All development on Mach3 ceased six years ago, any bugs or shortcomings that Mach3 has
it will always have.

There is a parallel port motion controller called Darwin ($25 license fee applies) for Mach4. It has limited realtime supports.
It cannot do single point lathe threading for instance. It was designed and written to be a cheap introduction to Mach4
rather than a complete motion control solution.

Mach4 was always intended to be used with an external motion controller. There are a number which have the required Mach4

Ethernet SmoothStepper  https://warp9td.com/
57CNC https://www.poscope.com/products/pokeys-devices/87
UC100 or UC300 https://www.cncdrive.com/
PMDX-424 https://www.pmdx.com/

There are three other manufacturers (Vital Systems, CSLabs and Galill) but their boards are all very much more expensive.

Of these I prefer the Ethernet SmoothStepper. At the current time it enjoys a clear advantage over its rivals in realtime supports
including lathe threading, backlash comp, realtime THC, laser vectoring/rastering, Spindle PID plus all the usual limit,
homing, probing supports you would expect of any controller. The cost of the ESS is about $180USD at the time of writing.
Note also that the ESS requires one or more parallel breakout boards which add to the cost. Simple C10s ($23USD) are
flexible and cheap up to a MB03 from CNCRoom ($180USD) for a quality three port sophisticated breakout board.

If budget is really tight consider a UC100, a 57CNCdb25 or a PMDX-411. They are all USB input to one parallel output (db25)
port motion control devices. They have 12 output pins and 5 input pins just like a single parallel port. They do not enjoy
a full suite of realtime supports but are none the less useful. They are all about $120USD. Don't be tempted by the Chinese ripoff
UC100s on EBay or Amazon, they are not real UC100s. While these devices may be attractive in terms of price you will be
very restricted because you have so few inputs.

It used to be the case years ago that everyone had just one parallel port. Many useful machines were built that accommodated
the limited number of inputs.....but these days with decent external motion controllers being reasonably and readily available
with 16+ inputs are the norm. I would have to commend the ESS, UC300, 57CNC or PMDX-424 over these single port devices
simply because they have more IO....you will appreciate it over the longer term despite being more expensive initially.

An example budget might look like this:
ESS                         $180
C10 (x2)                   $46
Mach4                     $200
Total                       $426

My wife left with my best friend...
     and I miss him!
Re: Mach 3 or 4 Controller
« Reply #2 on: September 22, 2019, 01:23:21 PM »
Hi Craig,

Thank you for taking time to reply and in such detail.

Taking into account all of your comments, I will purchase Mach4 (When the time comes).
I really like the look of the ESS board, which is in my price range.
I will also look around for suitable breakout boards so its nice and easy to wire up.

Hopefully the CNC hardware will be finished in a matter of weeks or so. I just need to sort out ordering the controller, hopefully the ESS and BOB.

Thanks again for your reply. It really helps.



Re: Mach 3 or 4 Controller & CNC room MB3 BOB
« Reply #3 on: September 23, 2019, 07:57:31 AM »
Hi Craig,

I am also very tempted to buy a MB3 breakout board for the ESS.
What do you think, looks like an excellent product to me offering many features over a simple low cost BOB.

Have you ordered from CNCroom before? If so are they reliable. They seem to get good reports reading around along with good reviews for the MB3


Re: Mach 3 or 4 Controller
« Reply #4 on: September 23, 2019, 08:59:02 AM »
I use MB2 breakout boards from Homann Designs (Australia). They are very simple, much like a C10, that is to say
no relays, no PWM and no opto-isolators.

Electronics is my thing, so if I want or need any of those features I add them as I require. This gives me great flexibility
with respect to pin assignment.

The MB03 by CNCRoom has a good reputation. Firstly all three ESS ports are developed. There is a reasonable balance between
inputs and outputs. The outputs which are intended for use as step/direction outputs are differential whereas the majority
of the others are single ended.

All reports are that CNCRoom is good to deal with and their products are quality made. I personally have not dealt with them
but ger21 has.......and he recommends them.

I like the flexibility of the simple bi-directional boards and I like that they are cheap by comparison to a MB03 and so I'll
stick with them.


My wife left with my best friend...
     and I miss him!