Thought it best to back up the system files before I do something silly and wipe them out - or lose the configs I've taken several weeks to craft to date. The file system is a bit clunky (to my eyes at least) and the Chinglish in this part of the manual is very strong. As I work daily with Chinese engineers, I am familiar with the machine translations that are commonplace, using tools such as Google Translate and the Baidu equivalent.
Google translate is excellent, not least the smartphone version that will literally translate the Chinese characters in a live video image even as you watch. And the online Google Translate browser app will make a pretty good job of converting Chinese test to English. But technical documentation that has been machine translated can be extremely challenging and the manual that Newker / Newkye provide contains extremely strong Chinglish. I may do better to get the Chinese original and have a go myself.
Anyway, in the process of trying to figure out how to copy files to my USB stick, I managed to wipe out a rather interesting looking example G-code file. I suspect this was a demo program for testing the various functions and commands but presumably I will never know now.
But before you can back up the system files onto an external drive, it seems you need to enter the low level password. It appears to be set on my controller but there is no mention of the initial password in the manual. WTF?
Z axis backlash:
Looking at the Z axis, trying to figure out why it grumbles / trembles, it seems that there is backlash going on. The Z axis on a turret mill probably has quite a hard life compared to the larger and longer X and Y axes. Certainly, after the rotational equivalent of about 50um of movement on the ballscrew, the load increases and quill starts to move. So I guess that the system gain is higher in that backlash zone - that initial movement requires much less drive current (torque).
The solution is presumably to measure the existing ball bearings and obtain some slightly larger ones, then repack the ballnut with them. This is the normal approach. You have to hope that the wear is reasonably even along the ballscrew, otherwise it will be rather stiff at the extremes and freer elsewhere. This can wait for now. I haven't even made my first cut on this machine yet.
MPG pendant:
I bought a generic Chinese MPG pendant from Aliexpress recently. It has all the basic functions you'd expect, like the ability to choose the active axis, the "steps per click" scaling factor and a red e-stop button. There was no documentation and although it's very much a generic design available from a number of sellers, the wiring is not consistent and there are clearly slight variations in the implementation.
I took the back off, partly to see what I was dealing with and also to figure out the connections in the absence of any documentation. It's certainly nothing like industrial in construction and build quality but it will have to do for now. I'll need to make sure the main e-stop button on the controller front panel is accessible and dependable in case the tits start to point upwards when I'm using this.
Damned fiddly, soldering 15 wires into the back of a 15 way Dsub connector, keeping the wires short enough to get the cable grip tight and the cover fitted back on afterwards. However, it seems to be connected correctly. You can check the correct connection and operation of the connector and pendant by watching the inputs page in the diagnostics menu.
Annoyingly, although the manual actually shows almost the exact same pendant internals, when connected up, I can't see any way to make the functions work correctly. The MPG itself can be made to operate, whether or not the "enable" push button on the side of the pendant is pressed. And the rotary switches for the axis selection and steps per click don't work. I can select those by using the front panel but it rather negates the purpose of having a pendant with loads of knobs on the front.
The manual suggests that the "Axis" and "Other" screens (parameters 1 and 2 in both) allow the MPG to be configured but it didn't seem to matter what I did, the best I could achieve was to disable the MPG itself.
Pressing the "Handwheel" button on the front panel brings up the same DRO-type screen as "Manual", with the active axis letter flashing. At the very top of the screen it tells you the steps per pulse (eg "X10").
So - successfully terminated the MPG to the Newkye controller connector and tested the connections👍. But haven't managed to get the thing to do much beyond the basic MPG handwheel function itself👎. I must be missing something😖!
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