z-axis are not turning... (3 replies)

Hello fellow builders,

i have a problem and i cannot find the solutions.
Finally i finished my prusa mendell. When i wanted to test it i saw that all motors worked exept the z-axis. The meke a sound but won't turn. i disassembled them and tested them again without anything mounted to the z-axis motors. I started the sotware Pronterface where you have 3 different options to test the motor. 0,1-1 and 10. When select 0.1 both motors turn. when i select 1, both motors turn. But when i select 10 both motors make 1 click (1,8mm) and then stop and only make a noise. when i assemble the motors again and test it the same way....only the option 0.1 does somethimes something, others do nothing...they only make a noise.

These are my specs of the prusa.
1 x computer power supply that delivers 12V and 8A
1 x sanguinololu v3.1A

personaly i think that it is a power issue.....that the motors are nt getting enough power to get the job done, but a do not know for sure...and bfore i go out and buy me one i would like to have your opinion.

Hope my englisch is undrstandable enough for you to read the problem.

Many thanks

Iwan
The Netherlands.