keypad

Both X and Y motors turn, but only in one direction. Z does not turn. Your Y and Z are not switched, it would appear.

each motor is connect to proper y,z,x connection.

What motors are you running? I have gotten bad motors before from surplus (once).

this info is list in the original post, nema 17.

Also, can you exchange the Z and Y motors and see if the non-rotating motor moves to Y?

see posting , states all motor work.

Since you have a grblshield v2 then you had to make connectors for the motor. Did you use the connector kit or make these on your own?

I’ve purchased your connector and crimp & solder the pins to the wire.

Can you make sure the crimp connections you made in the connectors are good?

again in the same posting: , states all motor work. state’s wire have been checked, meaning i move them from one x to y to z with and without the motor.

I’m reasonably sure it is the GRBLshield since its the only thing i haven’t change at this point.

Also, do you mean an R2 and R3 Arduino, or R2 and R3 grblshield?

Arduino UNO r2 & r3

Now, Can you explain to me what is happening with Y and Z flip flop? .

By flip flop, I mean they swap positions. If I send a command for y to move, z moves instead and vise versa. With one exception, z doesn’t spin/rotate. It hums. I swap motors around, all 3 motor work find. Even move the checked the cables from the shield to the motor.

Does this mean that when you enter the gcode line “G0Y10″ and the Z axis moves, and you enter G0Z10 and the Y axis moves? I cannot figure out how the grblshield would do this. The above should help confirm that this is what’s happening (or not)

Yes that’s what it is doing. I wont have time until later this weekend to run the above test, but I will post it when I do.

The pot are set to 12 o’clock.

Try setting the pots to their middle position (12:00 position) and repeat. That should be the position they were set before shipment. Check the pots to see if they are damaged. Do the screw slots look “clean”, or  are they stripped, which is usually an indication that the pot was damaged.

I’ve double check the pots and they are not damage & are clean looking.

Unfortunatly I don’t have the setup to check signal. Any other suggestions?

Try setting the pots to their middle position (12:00 position) and repeat. That should be the position they were set before shipment. Check the pots to see if they are damaged. Do the screw slots look “clean”, or are they stripped, which is usually an indication that the pot was damaged.

I’ll check this when i get home tonight. If they are set this way prior to shipment then they should still be that way since i haven’t touched them yet.

If I understand correctly the Z axis “swap” sounds like software, not hardware. I’m not completely sure what you experienced. You enter a Y movement and you get the Z motor moving? You might try driving grbl directly from Coolterm and taking Gcode sender out of the picture. One less variable. Also, if you have an oscilloscope or a logic analyzer check that the arduino is delivering the proper step and direction signals.

Is there some reference for how to do this with Coolterm?