Platform Calibration.

Hi. We zortrax m200 dont calibration. Back calibration is good. but front calibration failed.
I m clokwise turning the front bolt clocwise 1 degree.
Zortrax machine " turn front bolt anti clokwise"
I m anti clokwise turning the front bolt  1 degree.
zortrax machine " turn front bolt clokwise"
 

You are turning the front bolt 1 degree or 1 full turn?

1 degree won't do anything. 1 turn will probably do too much. 

Also, when turning the thumb nut, on my printer often the machine screw turns with it and nothing changes. It is not held at the top and you are turning against the spring pressure (if tightening). It helps (for me) to gently squeeze the platform down towards the carrier underneath, unloading the spring pressure from the screw as I turn the thumb nut. 

I had this once, probably too much difference in height between front and back. I had to clean the perforated plate and tighten all screws. There can get some ABS debris between the perf board and build plate when it is heating and expanding.

So: unscrew the perf board and clean well, then try to cailbrate again and see if that helps.

I had this once, probably too much difference in height between front and back. I had to clean the perforated plate and tighten all screws. There can get some ABS debris between the perf board and build plate when it is heating and expanding.

So: unscrew the perf board and clean well, then try to cailbrate again and see if that helps.

 
Read his post carefully. He says that before he turns the screw LCD displays "turn front bolt anti clockwise" and after the turn it displays "turn front bolt clockwise".
 
He's turning it too much per step.

Yes that could be but I had a problem once that looks like his description especially if he means 1 degree (would be hard to turn the screw 1 degree). I turned the screw just a little and then the program would tell me to turn it in the other direction. That went on and off until it drove me crazy and the program stated that the calibration failed. After cleaning it went better.

So clean the board and don't turn the screws to much in one go.