Sorry about the title, but I am beyond frustrated after dropping 6 grand and not getting any support from MaxNC on this issue.

So by work I mean reliably. I have 95% operation of my new machine, but every now and again an axis just stops. Sometimes it humms, sometimes it pops the fuse on the controller. But this is happening with no load on the machine and no tool, and the motors running slowly with minimal acceleration.

What I think is happening is that the feedback loop in the controller is getting confused about where the motor is, and getting it wrong. It then gives the wrong stepping signals to the motor. When the motor doesn't move, it assumes it's stuck and gives up.

Now how it gets into this state is the question. I am suspecting that it has to do with the "busy" pin. The controller says "Don't send me any more quadrature!" but for whatever reason I am getting a step or two. Then the controller gets confused. At least, this is my current theory.

Anyone else having issues like this? Any suggestions? I am starting to regret ever purchasing a MaxNC product..

Thanks!

Just found another post on this board where someone rebuilt their MaxNC controller due to similar frustrations. I am really hoping this is a "me" problem, but when I buy a product and it comes with software, I usually expect it to be configured properly. Maybe my expectations are too high for this kind of stuff, but as I read more on MaxNC it seems to me that many people do not think their controller is very good.

Disclaimer: MaxNC is not junk. I tried to fix that in the title but it won't let me.

Changed part of the thread title..........maybe one should not type when in the reactive mood. 
RICH

I've traced the problem to the encoders getting out of sync with the motors. It has nothing to do with MachIII or Vista. It appears MaxNC's controller doesn't like it if the encoder doesn't match what it thinks it should be. I could go the route of trying to debug this controller, but I'm just going to replace it with a Geckodrive.

Turns out it wasn't anything to do with Vista!

The MaxNC controller has a 12 volt 2 amp transformer in it. Now 2 amps to run 4 3 amp steppers just seems kinda dumb. If I run the machine off of a bench power supply with a higher voltage of 24 volts and 10 amps, it works just fine.... at least in the couple of tests I ran.

So it would seem that I was sold a defective controller, however I'd say the design is flawed. My theory is that the larger steppers (I bought the 160 oz/in option) are just too much for their controller. Either that, or they forgot to beef up my power supply.

Unfortunately I have no idea if any of this was a mere accident or I just got a defective unit since the company has not returned dozens of emails and phone calls for weeks and weeks.

I am still going to replace the controller with the GeckoDrive because frankly I just don't trust this controller.

Did you get an xml file from them for using Mach and for what version of Mach?
Can you post the xml and also info about the drive?

What exactly did you purchase?

I would think that the things should work for what they sell....at those prices .....very well.

RICH

Thanks Rich,

I'll get you the XML file this evening, along with the version of MachIII that max sold me. Thanks so much for responding!

I agree-- for that much it should work. I have a similar machine (MaxNC10) that provided many years of useful service, which is why I find it unusual that a MaxNC15CL machine produced 8 years later wouldn't have been vetted of all these issues many times over. Especially for the cost! I was hoping it was my fault but it really seems like I was either shipped a defective controller or the wrong one for the setup they sold me. I have been trying to contact the company to no avail for many weeks, so I have been forced to try to resolve this on my own.

The machine is a MaxNC 15 with the larger motors and 18" x table. It's  hooked to MachIII via the parallel port in the usual way running under "Max mode". The same problem occurs on 2 of my PC's, both are just plain vista installs with no other software installed or running. Those same machines run my OL maxnc machines just fine, but again it's the OL version.

The symptoms are easy to reproduce: Run any program without any tool and within a few minutes an axis will cut out and usually pop the fuse on the controller.  Issuing a "reset" clears the trouble.  I have traced the trouble down to the encoders getting out of sync with the motors. The behavior of the controller in this condition isn't documented anywhere, but my experience shows that the controller simply "gives up" and the machine carries on as usual. This is a dangerous situation as I've discovered when my Z axis gave out when drilling a hole. The table then starts to slide and the bit is destroyed and launches.

Upon taking apart their controller, I noticed a 4 amp 12 volt transformer (sorry, it IS 4 amps, not 2) powering all 4 axis. These are 3 amp stepper motors, so it seemed underpowered to me. I am able to get better results by running off an external power supply but alas I had my first failure yesterday so even this wasn't a real fix.

It is possible MaxNC sold me the "wrong" controller for my product. Perhaps there are multiple versions for the different machines. The first controller that came with my machine would die randomly due to a loose connection in the printer cable. They swapped out my board with the one I'm running now. But since I can't get ahold of them there is no way of knowing.

I'll find out the version/xml info this evening for you.

Thanks,

-Tj

Tj,
I or maybe someone else may be able to assist you if you get the info requested posted.  We may ask for more.
I am not going to pass judgement on the manufacturer as that is between you and they.  You have a new machine, so....
remember that if you do something recomended by anyone you may void a warrenty. That said, lets see how  the folks  here
can be of help.

It is possible MaxNC sold me the "wrong" controller for my product.

I don't know, but will take a look at their web site and see what they provide when time permits.
You shouldn't be blowing fuses.

Until then, no comments........

RICH

TJ,
I couldn't find anything specific on the maxcnc site for their drives. If you have info make sure you post it.
As expected, they also don't provide info on using Mach with their machines. I would expect that since they want you to use their controlling software.
As i looked through the manual there was mention of limitations on what versions of windows would work with "their" software. And specificaly it said no operating system greater than W xp home. The above is not relavent in sense since you are using Mach.

The modes which you can select in Mach, namely , Max CL Mode  is not covered in any of the manuals i have. There are some postings on the Yahoo group which you may want to have a look at just for info. One of them says that pin outs are automaticaly set for the Max cl mode and you can't change them and thus can't set them individualy ( hard wire changes only .....i guess if something is wired wrong).
Can anybody shed some light on that Mach Mode?

I just scanned the info and surely i missed something.......

Here is what i am thinking and frankly can be way off:
The Maxcnc driver when used with their software may be a closed loop system ( it controls the steps, adjusts, and may not fault ). Now mach sends pulses but is not a closed loop system , the steps are buffered, sent once, and you can't "put the cat back into the bag once it's out" so to speak.
Ok servo guys .....shed some light........

There may be additional quirks with their drives, it's DOS based ........
So what i am seeking is this:
Just what are the limitations of using their drives with MACH3 / if any?


RICH