My Z axis does not move..!!

[GolfOly]

Hi Friend,

I just finish assembly my i3 3D printer. I suddenly found problem. My printer cannot home and Z-axis cannot move both up and down. I checked jumper for motor driver. They are correctly set for A4988 chip. My main board is GT2560. I test by swapping connector of Z to X axis, it work just fine when I move it by manual control from Repetier (I use Repetier V1.60). My other axis work ok.
I did another test by disconnecting screw rod out from motor coupling and found that motor can move, but it stop easily when I hold it with my hand. I test again by disconnect one of z motor from main board, now Z motor can rotate and I cannot hold it with my hand. I try to swap motor driver A4988 from another slot, but result is the same.

What did I done wrong? Pleas help asap.

[Mark]

seems your Z axis is lack of power, you can try to increase the voltage since it has two motors to drive, check this link here:
http://www.geeetech.com/forum/viewtopic ... 13&t=17038

[GolfOly]

Hi Mark,

It does not work. I checked voltage, at first it was 0.8 V. I turn it to be 1.2 V, but result is the same. I check all of the rest driver, they are all only 0.8 V. I check all voltage to stepper connector, they are all 12.67 V. What should I do next?

[GolfOly]

Hi Mark,

I finally make it work. Problem possible come from lagging of stepper power when they have to share the current. I remove one of top holder out and now both of them can turn, I will figure out later how to make the mechanism better. Now I can also do the auto homimg. I found out that end stop switch was wrong connected to be "NO" instead of "NC".

I found another problem. It seems to me that X axis was going to wrong direction. When I do the homing, extruder will move away from end stop switch. I install end stop switch on the linear guide at the left side according to the instruction manual. What did I done wrong? Can I just swap the end stop switch to another linear guide side (to the right side)? Will it mess coordinate system of printer and software and result to wrong printing?

[Mark]

change the direction as the link shows:
http://www.geeetech.com/forum/viewtopic ... 13&t=17037