Z Axis issues

Hello all, I am having an issue with the Z height of printed objects, Items printed are coming out approximately 3/4 of the height that they should be. Machine stats:

HICTOP Prusa I3 3DP08
Marlin 1.1.0-RC7, have also tried Marlin 1.0 default from HICTOP
8mm/4start lead screws with a pitch of 1.25
Stock NEMA17 40mm stepper motors

I have verified that the voltage to the motors is correct. All travel moves work perfectly, ie I select 100mm up in the LCD menu or manual control through Repetier/Pronterface/Cura, the X Carriage moves 100mm up the Z Axis. There is no binding on the Z Axis. Both motors move smoothly by hand and under power. This issue only occurs during printing. Here are some pictures of 5mm Calibration Steps and 10mm cubes:







As you can see, the X and Y axis are running fine.

Any assistance is appreciated.

Thanks,
Frisk

I can't see the pictures.
If its OK manually then take a look at the Gcode and slicing settings.
A simple sanity check would be to go through the layers in repetier etc and check the zvalue at your 5mm step change layer.
How you get the code wrong is another question. Is the STL file correct?
You are either missing layers or the layer height is wrong.

I have corrected this issue, I swapped my Z motors from channel 3 to the spare channel 5 on my motherboard, made appropriate pin changes in the firmware, reflashed and ran the 10mm cube and 5mm calibration steps, both came out perfect. Voltage was not high enough on the original Z channel anymore, since I am only using a single extruder, this setup will work. Thank you all for suggestions and assistance.

Jamie