Why do my first layers turn out like this?

[Tish86]

I just started using Simplify 3D and my first layers are messy and end up making the bottom of my prints look bad. Below is a picture of two failed prints, you can see the extruder is either putting out too much on the first layer or I have some other setting wrong. If I continue the print it will just clump up and get stuck on the bottom of the final print.

DaVinci 1.0a
Repetier-Firmware-0.92
HatchBox 1.75 Black ABS @ 225C
Bed @ 100C

[CompoundCarl]

If the nozzle is too close to the bed, the plastic that comes out will be squished too much and it will look like that. So I would suspect that you need to calibrate the nozzle position. Go to the G-Code tab and adjust the Z-axis gcode offset. For example, entering 0.2mm will move the nozzle 0.2mm further away from the bed.

[AK_Eric]

If you feel the first layer is the right distance (trammed correctly), it could be overextrusion: Check the Layer Tab under 'First Layer Settings': This completely varies between printers, nozzles, filaments, and z-resolution, but I usually have my first layer height set somewhere between 75-90%, and my first layer width between 75-100%. Also in the extruder tab, see what your extrusion multiplier is set to. I always print in PLA which is close to 1.0, but other filaments could use a smaller value. If yours is bigger, it's going to squeeze out more material than the bed can handle.

[tmorris9]

Yea, looks like over extrusion to me as well.