3d printer help?

[laptopgeek]

I got a prusa i3 kit for christmas, and finished building it yesterday. However, I have 2 issues when I try to print

• The stepper motors on the z axis grind randomly, mostly when going down (but not always), stopping the extruder from rising
• The printer always begins printing about 2cm above the bed.

I've tried using cura 1.5 and the repetier software on win 7, but they both have the same result.

 

The bed is definitely level.

 

I've tried oil on the threads of the steppers, but it hasn't helped.

 

I think adding something to the start gcode to lower the z axis might work? I don't know what to do about the steppers though.

 

 

 

[tlink]

sounds like a calibration issue, which is probably related to the stepper motors grinding. a way of solving this could be by taking weight of the parts that move along the z axis so the stepper motors can handle it better. or am i interpreting this wrong?

[Sirgeorge]

Ya calibration issue would explain the "printing too high" problem. As for the grinding, I would say it would be a good idea to try playing around with the belt, maybe put a bit of silicon grease around the motor. I would need a closer look to see if that would actually do anything though. Pictures?

[laptopgeek]

Managed to fix both these issues, but have a new one

 

I fixed the steppers with just some grease, and fixed the printing in the air by changing the value it rises in the start Gcode.

 

However, now, whenever I try to print, the plastic doesn't stick to the bed. I'm printing a standard square shape in ABS, with the extruder at 230 degrees and the bed at 110. The plastic comes out the extruder, but just turns into a mess at the end of it, without any of it staying on the bed.

 

Should I use some tape on top of the glass bed? Or are my temps off?