Sintron Prusa I3 Printer - need help with steps calibration

hi I have built a prusa i3 printer from sintron and I am having problems with the printing

I cant even print a 20mm hollow box
the little robot in the Cura resources folder starts well then turns into dog poo very fast
I have slowed everything down in the intial layers but this hasn't helped much
I have attached my configuration.h file (I know I have set the z steps to 6400 in it and 4000 and 7200 etc.... all doesn't help)
It starts with the first layer everything sticks great to the kapton tape, then just continues to go around and around then finally the z axis kicks in but in no way does the elevation count for anything so the nozzle continues to go around till my box looks like a mess up clay vase on a pottery wheel
Printer - Sintron Prusa I3
Software - Marlin Prusa PT v1.3 ( that's what appears on lcd when it boots up
Cura for the models
PLA
Extruder temp 235
bed temp 75
I checked the rep rap calculator and I have M5 threaded rods with a 0.8mm pitch which converts into 4000 steps for my z axis ( this didn't fix the probem) I moved it up to 7200 and down to 6400 but still similar results.
Any help would be appreciated hopefully someone can point me in the right direction

Point: http://reprap.org/wiki/Triffid_Hunter's_Calibration_Guide

You should either use 4000 or 8000 steps/mm, depending on your drivers. Do you have DRV8825 drivers? Then use 8000 steps.

BTW: The extruder temp is too high for PLA. Better use 180-210°C.
-Olaf

the drivers are the A4988 drivers (pololu) and will check out the triffids guide thanks
I did calibrate when I finished building it, it starts out with the correct shape and size but just building up these layers are a disaster
I'm gonna try your suggestion and add a few pictures to this post so you can see how the prints are coming out
thanks again

here are my pla samples these were meant to be the 20m hollow box and the little oval one is meant to the ultimakers cura robot example, any suggestions would be greatly appreciated at this point

If you manually command the Z axis to go 100mm does it go 100mm?

Yeah all the settings seems correct it extrudes te correct amount and based on measurements it also moves the correct distance up and down

Then maybe your z-steppers are missing steps. How did you adjust the stepper drivers?

sorry had work all week yeah my motor drivers were too high gonna adjust them and do a full calibration again to see how this shitty cube comes out this time fingers crossed thanks for all the help this is a great forum for newcomers