Vertical Lines on my prints

I know there is a ton of threads like this one, but trust me, I've read them all and I coulnd find a solution.

The problem:
I have vertical lines on my prints and they are perfectly positioned.
If I print a square object the problem is noticeable only on the X axis.

The printer:
-Cartesian XYZ printer I designed and built myself (box style using aluminum profiles/extrusions)
-Im using GT2 belts and GT2 pulleys for the idlers and motors, all of them 20teeth.
- Ramps 1.4 with DRV8825, 1/32 microstepping.
- 200 steps nema 17 motors.
. Chinese cheap lm8uu linear bearings.

Things I already checked:
- Belt tension
- Driver voltage
- Rigidity of the frame and structure.


The distance bewteen each vertical line is 0.7mm aprox. Check image attached!

I don't know what's causing your problem but you might get better response if you posted it in the "printing issues" section [forums.reprap.org]. This section is for extruded aluminium frames so only people who have an interest in extruded aluminium frames are going to see your post and they probably aren't the best people to ask about your particular problem.

Constant underextrusion because of filament slippage? That was the cause for me when seeing similar results.

Looks so precise i'd say it was electronic in nature, possibly those drivers...but i'm guessing

Quote
MechaBits
Looks so precise i'd say it was electronic in nature, possibly those drivers...but i'm guessing

If it is the drivers, running the print faster will get rid of this. DRV8825's only cause problems when they hit their 'deadzone', and they're not getting enough power. I run 2A motors, and I only get this if a line is printed at a slight slant so that the axis must travel very slowly. Upping the print speed should get rid of any lines if this is indeed a problem with DRV8825. not a long term fix, but it narrows down the problem.