Upgrade? Chinese CNC Machine

[Carlb1058]

Hi All,

Total noob to the world of CNC, but not thick* - I'm sorta leaning toward thickendum at the moment though. I bought a Chinese CNC machine (yes I know now) and the controller a YooCNC is naff and couldn't cut a straight line if its life depended on it and it does so it's now one for the bin.

'Er indoors is getting a tad peeved shall we say at the fact that a) I bought a naff machine (eBay Australia: Buy new & used fashion, electronics & home d) and b) I gotta spend more money to fix it so with that said how do I go about sorting the controller, remembering the budget is getting slimmer coz I so wanna buy a Korg Oasys to pad out my ever growing synth collection

I've been looking at various controllers but this is where I get confused with amps watts and volts. The pictures attached are of the current controller internals showing Primary 220v Secondary 0-18v and 0-36v.
Can I just buy for example one of these
CNC 4 Axis TB6560 Stepper Driver Board Controller +CD | eBay
and mate it to my existing PSU/controller box or would I be better off buying something like this New CNC Standard 4Axis TB6560 Stepper Driver Full Kit & Motor/PSU/Keypad/Display | eBay
and just using my existing frame work which from what I can see is pretty damn solid.

Any help would be greatly appreciated.



Old naff controller box

Cheers
Carl

[Swarfing]

Yaki Da carl

Before you go wasting more money on controllers similar to what you already have. Tell us more about your machine. Straight lines could be down to that and not the electronics. You could probably do with some settings changing if your loosing steps etc. pics are good

[martin54]

I doubt if it's the electronics if it's cutting but not a straight line, that could be a number of things as has been said including the operator setting wrong speed & feed rates. Pictures would help as has been said. A video of it cutting would be even better.

[John S]

Don't bother with those boards, they are the same as what you already have

Two choices.
Either try to get it running better and from experience these boards do not like micro stepping, they loose steps. perhaps start here ?

Second choice is the box has a decent power supply so scrap the board and fit 3 decent drivers and a breakout board.
see
CNC Micro-Stepping Stepper Motor Driver 2M542 Bi-polar 2phase 4.2A Switch | eBay and
Upgraded 5 Axis CNC Breakout Board Stepper Motor Driver + 5V USB Cable + Mach3 | eBay

BTW does anyone recognise the power supply board in that box ? A quick look on ebay doesn't get me anything.

[Jonathan]

Might not even need to get a new PSU to use with the m542 drivers. The transformer says 36V on one of the secondaries, which is ideal since when rectified that will give just under 50V. It depends what rating that winding is on the transformer, but you might as well try it if you do decide to get the drivers that John S (and I) recommend. Do you have a part number / datasheet for the stepper motors this machine uses?

[John S]

Yes spotted that as well, even included it in the post that disappeared when I clicked on the picture again to check.
I reckon the tranny will kick enough out given that these motors only take a bit of power and volts on these things is far more important than amps.

When you have had your fingers in a switch on electric toaster you get a feel for these sort of things.

[Jonathan]

The motors look fairly small, so I tend to agree. However I've just noticed that the 36Vac output will be for the spindle, since that requires up to 50V and 230W according to the eBay listing. Unless that spindle is replaced another transformer would almost certainly be needed.

Still interested in that board that rectifies the current from the tranny.
I reckon they must be commercially available boards if they are in that box.

Hard bit is know what to search for on Ebay.

Er why, surely you don't want one? It looks like it does a bit more than just rectifying though - I think it does the PWM drive for the spindle.

[John S]

Still interested in that board that rectifies the current from the tranny.
I reckon they must be commercially available boards if they are in that box.

Hard bit is know what to search for on Ebay.

[Carlb1058]

Hi,

Unfortunately, all that came with the machine was a teeny disk with a manual on that when printed tells you nothing in regards to tech specs, essentially it's just an overbloated example of how to find the power button.

My biggest problem is when it comes to electronics I have the IQ of a door knob, if the thing was powered by a Meriden twin I'd have it torn down, rebuilt and running as sweet as nut but it's not so it's back to being as bright as a blown bulb for me How many of those m542 drivers would I need, three - one for each axis or is my thickendum sowing again?

Cheers
Carl

Ignore the last question John S pointed out I'd need three *slaps forehead*

[John S]

Looked at the pic and the steps are out on the setup.
You probably don't know what that means which proves you are thick but no sweat for a Welshman living in OZ we all feel sorry for you.

OK we need a DECENT picture of the stepper board in the controller box from vertically down, hell take 3 or 4.
then we need a screen shot of the setup page in Mach.

That's Config > Motor Tuning

Next double check it does have ball screws and the pitch is 4mm

If you get stuck, shout up we need a good laugh.