Lowrider cnc v3 3d space inverted in z axis

LowRider CNC Troubleshooting
1

So how i would describe the issue: I have dualLR firmaware, bed size set.
it homes y and x axis ok and so it will do with z axis.

But issue is that when doing crown test, z axis starts from top! it wont touch the bed like whole z axis would be flipped upside down.

when g code tells z axis to +5 mm so spindle could get clearance… it comes down -5 and when it tells to -1 it goes up. Cant wrap my head around with this one, as on my 3d printer its the opposite way. zero starts from bed.

#define X_HOME_DIR -1

#define Y_HOME_DIR -1

#define Z_HOME_DIR +1 // -1

Would this be the problem?

2

Those homing directions are correct. It should home to the top on a low rider.

It sounds like at least your Z motor is backwards. You can reverse the stepper connector to reverse its direction.

docs.v1engineering.com/learn/coordinates/

1 Like
3

Like i mentioned earlier. It homes z to top and x &y like it should.

Screen button +z goes up and - goes down.

But runnning gcode test crown. The crown would be flipped upside down. Starting from top. If i look at it from 3d point of view.

So it starts to do crown gantry up position. Like z endstop position would be z0 point.

Will check today if i have z axis cables cross plugged and wrong motor direction.

If i put it this way, z axis works sameway as printer with fixed gantry and bed moves up and down.

But it should be the otherway around. Gantry moves up and down logic.

4

What software did you use to generate the Crown gcode? You indicate that on the LCD, Z moves correctly, am I right?

5

It was the ready testcrown gcode.

Yes z goes down from -z and up from +z

Zmax is 200 and 120 when milling bit touches the bed.

6

Was thinking that as using skrpro and newest firmaware and dualLR

Maybe i should make crown gcode with z origin at top?

Also should i limit the z axis to zmax 80?

7

Top of Block, yes, I was wondering if that was the case. I believe the the ready test crown is top of block but I may be wrong, always generated mine myself.

8

The premade gcode is what you should use. It has been well tested. It starts by sending a G92, and should be set at the top of the block (or with the pen touching the paper). The point of the test crown is to eliminate any decisions from CAM and just check out the machine.

9

Thanks all, turned out to be my user error. Had couple of test runs today, had cut one strut and second one failed. Z axis leadscrew has issues. But so far it works now.

will clean up leadscrew and take spare nut for it. Just in case.