Help finding good BOB for 5 Axis mill with KBMM-125 spindle speed controller

Brand new to the site.

I inherited a Sieg X3 CNC mill with X, Y, Z, lathe, and rotational stage stepper motors and a spindle being driven by a KBMM-125 controller.

It is currently running on an old Windows 7 machine through a parallel port BOB.
Spindle speed control is only via a pot on the front of the machine.

I am looking to upgrade the BOB to a USB connection so I can use a new laptop to run it.

Control software is Mach3 on the old machine and I've downloaded Mach3 on the new machine and have the license file moved over.

I am having trouble finding a USB BOB that has 5 (or 6) stepper axis, runs through USB and has an analog output to drive the spindle through the KBMM-125.

What I think I need to do it get such a board and wire the 0-10v analog output into where the speed control pot is on the KBMM-125.

First, am I approaching this correctly?
If so, any recommendations on a BOB?
Ideally, I'd love some help with a wiring diagram for the spindle control, but if I have the right card with the analog output, I think I can figure that out.

I've seen the C6 board that uses a stepper channel to make an analog signal, but I have 5 channels already and figure it's easier to just get a board with the analog output native to the board.

Thanks for any help!
Cheers,
Mark

Hi,
I would recommend an Ethernet SmoothStepper, it is Ethernet connected as the name suggests but has much greater noise immunity and less jitter.

Note that the ESS is a motion controller, not a breakout board, so that is required in addition. I would recommend an MB3 by CNCRoom. It has all three ports
of the ESS developed, which includes up to to six (differential) axis channels, a fully isolated 0v-10V analogue output for spindle control, relays, plus all the usual
inputs and outputs. It has 51 inputs and outputs in total.

CNCRoom sell both the MB3 and the ESS as a combination:

https://cncroom.com/en/product/ess-mb3/

Craig

Thanks for the suggestion Craig.

Sounds like a reasonable option, though a bit pricier than I was expecting. Guess you get what you pay for in the end.

I'll look a little closer at the details when I have a few more minutes.

Any other good options out there?
Cheers,
Mark

Hi,
yes, the ESS and the MB3 are not the cheapest, but they work as advertised, whereas many of the cheaper options do not, or at least without a lot
of messing around. I don't know how many millions of dollars of cheap gear is lying around because the new owner could not get it to work, and the Chinese manufacturer
might as well be China in some other galaxy.

Craig

as Joe mentioned the smooth stepper is an option , as is ucnc 400 . They come at a bit of a cost but both plug into your current bob which pretty much makes them plug and play . I own both but never did put them to use so I can't vouch for them . But , from what I've seen guys are happy with either
I would suggest staying away from the usb uc100 from cnc drives , that thing is a turd that too often loses connection

Thanks metalmayhem. Unfortunately, the spindle is not functional with my current setup, so I need something more than just a ethernet to parallel port device.

Hi,

Quote:

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Unfortunately, the spindle is not functional with my current setup, so I need something more than just a ethernet to parallel port device.

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While I'm not an especial fan of CNCDrive equipment like the UC400, to characterise it a an 'Ethernet to Parallel converter' is just plain wrong. The UC400 is a motion control board,
it accepts numeric trajectory data from the CNC PC, say Mach or UCCNC, and then converts those numeric commands to accurately timed pulse streams to control the axis
motors. Those output pulse streams are arranged as parallel port outputs, more for historical reasons than any particular need. This makes them way WAY WAY smarter than any
converter...it is a genuine and good motion controller.

The Ethernet SmoothStepper (Warp9TD) is also an Ethernet connected motion board that outputs three 'parallel ports worth of IO'. To characterise it as an Ethernet to Parallel converter
is equally as wrong.

The reason that I favour the ESS is not actually so much as the ESS but rather that it is perfectly matched to the MB3, and the MB3 has a rather smart and well thought out analogue
PWM output circuit called 'Anaspeed' by CNCRoom. I think this circuit will be of most use for OP's spindle control.

I built a new mill and have been using it for about 2.5 years now. I use an ESS and have done for 8-9 years. Because my machine is servo driven I wanted a specific set of features
of a breakout board, somewhat different than the MB3...so I built my own breakout board, electronics is my thing. It does not have as sophisticated PWM output circuit as
Anaspeed, it still works very well and within 1%-2% of linear....so entirely good enough.

Craig

I'm getting a bit closer, but a little confused.

I think the ESS-MB3 does what I need stand-alone. Just plug all my hardware wires into the right spots and set up the software. Unfortunately, a bit pricier than I hoped and currently out of stock.

My comment about ethernet to parallel was based off looking at the wrong image. I saw a UC100 metalmayhem warned about and that does look like it just plugs into my existing parallel port and on to the existing BOB, which doesn't do what I want right now, as my existing C10 bob doesn't get me spindle control.

The UC400ETH seems functionally more like the ESS-MB3, but it also looks like it runs through a ribbon cable to plug into an existing bob? Am I getting this wrong?

I also see a UC300ETH which seems to have the capabilities I need, but all of the connections are ribbon cable connections, so I'd need to add ribbon cable breakouts, unless I'm missing something. I just have a bunch of wires screwed into the current bob. No ribbons.

Thanks for all of your help!
Mark

you can connect from the ribbon direct to your bob if its a basic db25 bob , it's just a matter of purchasing a ribbon to suit . I think mine came with but can't remember , otherwise they can be purchased from ebay fairly cheap

Hi,
I suspect you'll need a specialized circuit to control the speed of your spindle, you are replacing a potentiometer rather than a straight varying 0V-10V.

The C10 is a basic BoB and does not have any PWM output circuit, but you could make your own circuit, a half a dozen components or so on some vero-board.

Craig

Hi,
there are two ways to control this unit, either by replacing the potentiometer an opto-isolated MOSFET switch OR supply an isolated varying 0-9V analogue signal in voltage follower
mode. Of the two methods the voltage follower mode is the best.

Craig

Hi,
this is what I had in mind. The DC-DC converter is a little box, costing about $10, that takes, in this case 15V input and outputs 15V but isolated. These things are cheap and a real
boon to designers, years ago this was complex and expensive....now there are dozens of these things to choose from, with varying input and output voltages.
I've use an LM317 linear regulator to drop the isolated 15V down to 9V which is adjustable with the trimmer. I use an MCP1416 non-inverting MOSFET driver as a rail to rail
output amplifier, and a single resistor/capacitor as the smoothing filter.

The inputs required are 15VDC supply, and the PWM output from your BoB, the C10 can do that no sweat, and the output is a varying 0V-9V isolated DC output.

This is similar to the Anaspeed circuit built into the MB3.

Craig

Craig,
OK, so I think I'm getting even closer. Let me validate a few things. I'm a materials guy, not an electronics guy, but I can learn and have done my share of soldering and electronics troubleshooting.

So, big picture, my current old computer is actually converting the g-code and creating the signals needed by the stepper motor controllers, etc. This is passed through the parallel port wires to the bob and distributed to the relevant controllers and devices.

To switch to USB or ethernet for use on a laptop, we move the signal creation to a new device, the suggested motion controllers. This receives the commands and creates the relevant signals (thus less noise). These signals are then passed on to a bob and the rest is the same.

Separately, to get spindle control, you are proposing converting the PWM signal that my bob is capable of into a 0-9v isolated signal that the KBMM-125 can use instead of the potentiometer. I was trying to purchase a bob capable of the 0-10v output, but this approach makes sense.

So, unless I'm missing something, I can do this in stages. Get the spindle going now using my old computer, then get an ethernet motion controller and connect it to my current bob using a ribbon to parallel cable.

Did I get this all correct?

So, I'm sure I'm missing something here, but if I were to purchase the ESS-MB3, that has an isolated 0-10v output that I could just wire into P1 and P2 on the KBB? I know the KBB wants 0-9v, but it seems I should be able to set the scale in Mach3 to not go to 10v.

Thanks again for all of your insights!
Mark

Hi,

Quote:

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So, big picture, my current old computer is actually converting the g-code and creating the signals needed by the stepper motor controllers, etc. This is passed through the parallel port wires to the bob and distributed to the relevant controllers and devices.

To switch to USB or ethernet for use on a laptop, we move the signal creation to a new device, the suggested motion controllers. This receives the commands and creates the relevant signals (thus less noise). These signals are then passed on to a bob and the rest is the same.

---

Yes, that is a good summation. What you may not know, nor will you until you try, but a USB or Ethernet connected motion control board is light years ahead of a parallel port, much smoother
and capable of much higher resolution, and your PC will run just that much sweeter as it does not have to generate pulse streams, which is a PC shortcoming.

I proposed the circuit so that you could still use your C10 BoB, and thereby save some money rather than buy an MB3. The Anaspeed circuit of the MB3 is very similar to what I have proposed, namely that its analogue output is isolated.
The MB3 has an adjustment on it so it could probably be tuned to 0V-9V to match your controller. The MB3 is itself around $200USD, so its not cheap, but I think fair value. My own home brew BoB cost about the same
and is in many respects very similar to the MB3. The other advantage of the MB3 is that its fully developed to use all the IO of the ESS, all 51 inputs and outputs. You can increase the functionality of you machine with
more inputs and outputs to your hearts content, whereas your C10 is likely maxed out as is.

If you get really stuck and just cannot afford an ESS/MB3 combination, let me know I could make a little circuit board and populate and test it and send it to you, it would be the size of a matchbox,
and about $25 plus postage.

Craig

Craig,
That's an amazing offer. It's not really that I can't afford it, I am always value conscious.

As I mentioned above, the ESS/MB3 shows out of stock.

The UC300ETH-UB1 seems like it has similar functionality? Thoughts?
https://cncroom.com/en/product/uc300eth-ub1/

Just to be sure, if I get the ESS/MB3, or UC300ETH-UB1, that becomes my bob and I just attach my existing wires to it and the C10 goes away. Connects to my laptop and spindle runs on P1/P2 of the KBB. True?

And if I were to make the circuit you so generously shared, I can use it with my C10 and get the spindle going, but I would need to add a board like the UC400ETH to attach to my laptop instead of the old PC. Yes?

Mark

Hi,
the UB300 is perfectly good, although it misses on a few features that the ESS has, but is none the less perfectly OK.

CNCRoom may be out of stock of the ESS, given that the ESS is US made, but surely they have their own MB3 board? If that's the case you can pick up an ESS anywhere, including direct from Warp9TD.

Quote:

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Just to be sure, if I get the ESS/MB3, or UC300ETH-UB1, that becomes my bob and I just attach my existing wires to it and the C10 goes away. Connects to my laptop and spindle runs on P1/P2 of the KBB. True?

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Yes. I'm assuming the UB1 has the same Anaspeed circuit...seems probable.

Quote:

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And if I were to make the circuit you so generously shared, I can use it with my C10 and get the spindle going, but I would need to add a board like the UC400ETH to attach to my laptop instead of the old PC. Yes?

---

Yes, that is correct, you'd retain the C10, and add the little extender board but you'd still need a motion control, either a parallel port or one of the ethernet or USB connected motion controllers.
I'd avoid the cheap Chinese made motion boards, they are more hassle than they are worth.

If you are inclined at some future date to upgrade to Mach4 then the ESS has features that the UC300, UC400 and UC100 do not, to the extent the the price premium for the ESS is moot.

Craig

OK. I think I've got it.

I'm out for a couple of weeks. My son and 230 of his good friends are going to march in the Macy's Thanksgiving Day Parade in New York City and I'm going to chaperone. Then a work trip. I'll update when I get it worked. I expect no problems now thanks to you two!

Cheers,
Mark