Newbie (ageing rapidly!)

[Doddy]

MM: I don't have the NVUM, but do have the NVEM (the ethernet variant), and can say that they are largely okay, but come with issues, the first one being that they have a fixed pulse width of 2.25us output to the stepper drivers, from memory (and that ain't great) negatively switched but capable of sourcing or sinking current. The default installation in the manual suggested switching the positive input to the stepper driver and grounding the negative input - with my cheap stepper drivers that lead to the LED in the optocoupler being "On" significantly longer than "Off", coupled with the low performance optocouplers (4n25) and saturation on the phototransistor meant that the stepper drivers were missing steps (scoping input vs output showed a grim transfer function). So, word of warning on the NVUMs (assuming the motion controller is largely the same) - check that you're not in a position described above, changing the arrangement above can help (as can better stepper drivers or replacing optocouplers.... but you're a way from that yet by the sounds of things).

I've never tried USB on a CNC machine (only PPBoB and Ethernet). I did, however, once have a USB interface to a RepRap 3d printer. That was temperamental (occasional missed instructions which lead to offsets in the print space) and a shared view on the inter web pointed at the reliability of USB. Fortune smiled upon me and I managed to shear off the micro USB socket from the board by tripping over the cable - the easiest fix for me was tacking a bluetooth serial interface directly onto the Melzi board. Strangely, BT was infinitely more reliable than USB in that environment. I think USB and steppers and potentially disimilar grounds don't co-exist well.

The NVUM ??? plugin buttons - I have those with the NVEM. Not figured out which button does what but again, from memory, there's only a couple of very basic options to play with on the config screen, so long as those "stick" then the two buttons are likely OK and CANCEL - press one and check the config sticks. The ddream driver - sounds about right - and I think indicates this is likely a rip-off controller, but works to a fashion for me on a NVEM.

Open up the NVUM - you should find the inputs are Optocoupled already so external conditioning is not really needed. Just be aware that the ABS injection moulded case - the receptacle for the screws doesn't butt against the mating face on the other half of the case - so it's easy to overtighten and rip the plastic apart. Tighten to 0 white-knuckles loading.

What exactly doesn't work for you with the NVUM? I guess you've tried jogging with no joy?, I know with the NVEM driver on first start-up I can find (though never really bottomed it) that I can't jog until I home the machine. Maybe a driver issue, but I usually have a 2 minute tussle persuading the machine to start moving - either a G1 X1 feed through the MDI or a home resolves and I then get distracted and never investigate further.

[Neale]

I know with the NVEM driver on first start-up I can find (though never really bottomed it) that I can't jog until I home the machine. Maybe a driver issue, but I usually have a 2 minute tussle persuading the machine to start moving - either a G1 X1 feed through the MDI or a home resolves and I then get distracted and never investigate further.

Mach3 has the same "feature". A bit of a pain if you've parked the gantry at the far end of the machine at the end of the previous session as homing speed is slower than usual rapid speed. I found that it was because I have soft limits enabled - Mach3 errs on the side of caution and doesn't allow jogging until homed as it can't check soft limits otherwise. Don't know if it's the same on your controller. Just a thought.

[Doddy]

Mach3 has the same "feature". A bit of a pain if you've parked the gantry at the far end of the machine at the end of the previous session as homing speed is slower than usual rapid speed. I found that it was because I have soft limits enabled - Mach3 errs on the side of caution and doesn't allow jogging until homed as it can't check soft limits otherwise. Don't know if it's the same on your controller. Just a thought.

Cheers - you might be right. I'm doing a lot of work on a plugin for my machine at the moment and learning an awful lot of the weirdness of M3 (like default feed rates on initialisation).

[Neale]

That one really narks me - first thing after startup these days I overwrite the feed rate to 3000. Initial jogging at 6mm/min is awfully tedious...

Some time I'm going to be doing a CNC conversion on my own vertical mill, so I'm finding these discussions of various control options very interesting. One thing I know is that it's unlikely to be Mach3! Seems to be some good options available or close to available.

[Desertboy]

I'd try and make one of your USB solutions work.

The Nvum controller seems a good place to start.

Join this forum then read this thread back to back, you are not alone.
https://en.industryarena.com/forum/h...-315210-5.html

This guy has an updated beta driver
http://www.opalsfromaustralia.com.au/cnc/

He has same controller as you, should be able to help you get going and is a forum member on industryarena.

I had a lot of the same issues. Went to win 7 32bit and a lot of them stopped. Still have a few issues but the router now runs for hours no problem.

Before I went back to 32bit operating system I tested on another 64 bit system and had the same issues. I was about to buy a different controller but decided to format and try again. Turned out to be something in the 64 bit operating system. Took me months of frustrating fault finding after work.

The nvem now happly runs my Alpha 1300x2500 router and has paid for it's self several times over.

[JAZZCNC]

That one really narks me - first thing after startup these days I overwrite the feed rate to 3000. Initial jogging at 6mm/min is awfully tedious...

This is what annoys me when people knock mach3 when really it's the user ignorance. If you go into General Config you'll see initialization String just enter the feed you want into there and will always be set to that when Reset.

[Neale]

I thought that I had tried that (it's obvious that there are initial settings and I did look for and find where they were set) but it didn't work. So, probably user error rather than user ignorance in this case! I'll have another look - thanks. It's only a nark, hardly a show-stopper, and less important than not being able to dual-axis home with my IP/M. But I used one of those with my eyes open and I can work round that easily enough. Mach3 works well enough for me but there are always odd items where you think, "I wouldn't have done it quite like that!"

[JAZZCNC]

hardly a show-stopper, and less important than not being able to dual-axis home with my IP/M. But I used one of those with my eyes open and I can work round that easily enough.

This can be done with IP-M if you want to do it. Just takes little out of the box thinking but agree it would have been better if Cslabs made it possible in software.