cant level the bed

Hello
I have a prusa i3 dual extruder, and im a beginner.
Im trying to print a simple cube with only one extruder, but the problem is that the first layer is ok and the next ones are not being printed or printed some with "touches " of plastic. I think that the problem is the bed leveling - as i understand, if i print in 0.2 level thickness, i must level the extruder in four courners as a thickness of 3 times folded A4 paper - 0.05 *2*2=0.2
But still, no result - or its too high, or, if i pause and try to take the bed upper it gives me the same horrible result.
Please, help me, what am i doing wrong? How can i possibly level the bed perfectly ?
The settings are
thickness 0.2
PLA 1.75
0.3 extruder
extrusion rate 2.5 - i know its very high but i read somewhere here that it helps...
THANK YOU!

Level the bed once with one sheet of paper thick.
The slicer knows where to put the nozzle depending on layer thickness after that.

Read this!

There's something wrong with the extrusion rate.

-a

I had problems when i frist started trying to level the bed also.

What i ened up doing was just leaving out the paper all together.

I drop the Z down to its end stop. (make sure the bed is a few mm below the nozzle.)
Then i raise up the bed untill the nozzle touch the bed.
I started in the center. Then move the Z up 1mm and more it to the Left front conner.
Did this for all four conners. Then back to the center and check it.

Once i got this done it printed just fine.
I have an all metal bed so i added a auto leveler and my prints have all turn out great.

*edit

also forgot to add.
Make sure your left and right side of your x axis are level.
If one side is higher the there other it will effect the Z high while its moving up

Edited 1 time(s). Last edit at 07/03/2015 11:29PM by xile6.