Thread: Another chinese CNC router

A couple of posts are missing - any ideas what happened?
They magically re-appeared again????/

I sent an email to the maker of the routers electronics, Yoocnc, in a vain hope of getting some technical information to assist in troubleshooting should the problem be more than one of my lack of Mach 3 expertise. To my surprise, I got a reply - in Chinese -which pointed out they only sell to resellers not direct and to try a reseller such as this one Home - carving-cnc.com.
This site lists replacement BOB/interface at $10, drivers at $17 - good to know.

They also list a 4th axis for these CNC routers for only $190! Add half as much again for DHL shipping and it's still pretty cheap.

Originally Posted by rodm

Go to motor tuning and set steps to 400, velocity to 1000 and acceleration to 1000 for each motor. Also set the step pulse and direction pulse to 2. This will give a guaranteed movement on your setup if everything else is right - once you are running then change them to the real figures.
You need to press enter key after each entry then save each axis when you make changes here or they revert to original settings. Save setting again and exit Mach3 then open again and check those settings have been changed.
I am at work and don't have a Mach3 screen in front of me so wing your way if the instruction are vague for a while. I'll check back in a couple of hours.

Disconnect any peripherals such as manual MPG etc and just leave the reset or estop active. Get this going in the simplest form through Mach3 direct control then eliminate one at a time the other issues.

Don't worry about diagnostic screen at this stage. You are 9 parts there if the motors all lock up.

Thanks Rod,
I tried these suggestions but no joy. Motors still lock up but no movement.

Noticing that the led on the interface board seemed a bit dull, I thought it might be a problem with the voltage level/current supplied by the parallel port.
I found a 5volt power supply and plugged it in to the connector on the interface board and away i went.

Thanks to Rod for the assistance and patience.

I've just noticed that the Z buttons move the Y axis and the X and Y buttons move the Z - but at least it MOVES!

Good to hear.
You had it there yourself without realising.

Looking at the link you provided these are the pin settings
StepX 2
Dir X 3

StepY 4
DirY 5

StepZ 6
Dir Z 7

Estop Pin 10

These are standard settings for most boards.

Those are the settings documented and printed on the interface board.
What had happened was that I removed the interface board earlier so I could find a suitable power supply connection for the 5 v input. When I put it back in the box, I managed to swap over some of the connectors to the driver boards

The Z axis seems to bind a little and the whole thing rattles as I haven't screwed down the t-slot - but it moves!

I've now put in the recommended motor tuning and the X and Z axis are much smoother.
There's a definite problem with the Y axis though and I'm pretty sure it's an incorrectly wired cable.
Previously I mentioned a cable problem on the X axis where two wires were swapped compared to the other cables. It wasn't an issue as the wires were swapped at both ends On the Y axis only one end is swapped and I think this is causing the problem. The motor makes a noise but does not move.
A job for the morning.

Well done Geoff

Looks like you got one of the good ones.

Bob Willson

Thanks Bob,
I think I was just lucky and that I got a supplier who beleived in packing things properly. I seem to be having a much better run than Boomeranginfo had with his purchase.

A bit more playing around today shows that the X axis, while it moves, does seem to bind in spots (not the same spots) and makes a hell of a noise when it does. Could be a loose motor coupling or the linear bearings need checking for alignment (can they be adjusted?)

Originally Posted by snowyskiesau

Could be a loose motor coupling or the linear bearings need checking for alignment (can they be adjusted?)

Yea, they have a grub screw which compresses the linear bearing inside the housing to make a tighter fit.

Sure it's not the stepper motor losing steps? They make a grinding noise when they stall.

'ginding noise' sounds about right
The motor coupler is definitely loose as I can hold the ballscrew and turn the knob on top of the motor. I must go and find those t-handle allen keys...

I undid the screws holding the ballnut to the gantry and with the ballnut at one end, I can easily move the gantry along its full travel - make a 'clicky' noise which I assume it the ball bearings rotating? It seems very solid without being tight.

One thing I noticed is that while the ballnut housing is a very close fit to the bottom of the gantry, the actual ballnut flange sticks out a little, To get the ballnut housing back under the gantry, you have to apply a bit of downward pressure to get it to fit.

The ballscrew is probably finding it's own centre so I would let it hang out a little if it wants to. It is more about alignment to make it turn without binding.

As a matter of interest turn the ballscrew and see if the nut moves around a little - that will tell you how straight the screw is.

When you squared the table it may have casued a little mis-alignment of the ballscrew so loosen the nut there and let it reset itself too.

Originally Posted by snowyskiesau

Thanks Bob,
I think I was just lucky and that I got a supplier who beleived in packing things properly. I seem to be having a much better run than Boomeranginfo had with his purchase.

A bit more playing around today shows that the X axis, while it moves, does seem to bind in spots (not the same spots) and makes a hell of a noise when it does. Could be a loose motor coupling or the linear bearings need checking for alignment (can they be adjusted?)

different model with diffident controller , the ones we bought were the 6545 , looks like the same parts , but the spindle is 1500watt instead of the 800watt and an extra 50mm on each axis

it seams the 6040 are ok