Cube - Z Axis dropping too fast

Had an acceptable quality performance with the mbot3d Cube, however, recently was getting poor prints and thought my models are broken. However, when I tried to print a s3g file from the SD card which I had printed in the past, it came out double in height and all kinds of bridges. The print was very brittle and fell apart while removing from the print bed. Is there some way to fix this, maybe reducing the Z axis angle or something? If anyone has more insight, please let me know. Thank you.

I think I have simillar problem, My z Axis is to tight and when it moves the bed it’s jumping little. I think the problem was the bushings, becurse the first 2-3 layers are always bad for me and i think thats becurce when the bed should go down, it dossend slide down it’s self, it’s need to be dragd down.

So last night i starting change de bushings to real LM8UU and I hope that will solved my problem, I’m not finish yet, have one left and later today I will do a calibration and test print with that, I hope it will be better then first time use.

I will let you know, and se if thats something ju need to do also.

My All time best print… ( sadly ) same file, just with diffrent Z bushings.the high of the object is a big diffrent, I dident know it was that high.

Bushing lm8uu and electric tape,