Problem with prusa i3 pro b z axis

[pczombie]

Hi,

Just got my first 3d printer the prusa i3 pro b. I bought this one from eBay https://goo.gl/iwpmWF
I have everything working except for the z axis. so far the only way I have managed to move it is change the value of the zsteps/mm from +2560.0 to +0094.8 this allows me to move it up and down in the move zaxis screen by either 1mm or 0.1mm.
doing this only allows me to move them does let the printer move up while printing. The printer does everything else perfectly. I can start to print something and it will do the first few layers then starts dragging the head on the plastic
If I use the default settings the steppers just scream at me and refuse to move up or down.

I have tried=

turning both steppers using the x axis cable both turned independently no problem there.
using each stepper cable to move a stepper motor using the x axis all cables and steppers work.
I have measured the pot for the z axis driver board and it is -0.09 I have tried -0.04 and -0.10 I am a bit confused as to why its -0.09 and not just 0.09?

I have also been unable to get the cura software to connect to the printer it says error baudrate.

I would like to try and adjust the firmware or flash some new firmware and see if that fixes anything. any thoughts would be greatly appreciated.

[William]

Hi,

Just got my first 3d printer the prusa i3 pro b. I bought this one from eBay https://goo.gl/iwpmWF
I have everything working except for the z axis. so far the only way I have managed to move it is change the value of the zsteps/mm from +2560.0 to +0094.8 this allows me to move it up and down in the move zaxis screen by either 1mm or 0.1mm.
doing this only allows me to move them does let the printer move up while printing. The printer does everything else perfectly. I can start to print something and it will do the first few layers then starts dragging the head on the plastic
If I use the default settings the steppers just scream at me and refuse to move up or down.

I have tried=

turning both steppers using the x axis cable both turned independently no problem there.
using each stepper cable to move a stepper motor using the x axis all cables and steppers work.
I have measured the pot for the z axis driver board and it is -0.09 I have tried -0.04 and -0.10 I am a bit confused as to why its -0.09 and not just 0.09?

I have also been unable to get the cura software to connect to the printer it says error baudrate.

I would like to try and adjust the firmware or flash some new firmware and see if that fixes anything. any thoughts would be greatly appreciated.

Hi,
Some thoughts in my mind：
1.You said why -0.09 not just 0.09 cuz you connect the red probe to the negative electrode and the black probe to positive electrode?So change the connection order,red-positive vs black-negative.
2.About the baudrate,what value you've set in your cura?The value shoule be the same as the one in your firmware,you can check it in your firmware,i guess the value might be 115200 or 250000(mine is 250000).

[pczombie]

thank you for your reply. I am newbie and I am sorry if my questions cause headaches. I had the black on the GND solder from the z axis driver board and the red on the pot. also where can i check the firmware on the machine it self or through a program on the pc via usb?

so far I have not been able to get cura to connect. Where could i download compatible firmware for flashing my printer? I would hate to flash the wrong one.