Skirt Settings

Skirts are really useful for priming your extruder prior to printing. I generally print with a skirt offset of 4 mm and 2 outlines. However, changing the offset to 0 mm, offers the ability to create a "brim" that will connect to your part and help create surface adhesion. For more information on skirts, brims, rafts, this tutorial is very helpful:

http://www.simplify3d.com/support/tutorials/rafts-skirts-and-brims/

Skirt Extruder

Selects the extruder to be used for printing your Skirt

Skirt Layers

How tall your skirt will be. If you want the skirt to be as tall as your part, you can just place 99999 in this field.

Skirt Offset

How far away your skirt will be from your part. 

Skirt Outlines

# of perimeter outlines for your skirt.

Raft Settings

A raft offers a base understructure that will contour to the outline of your print, increasing the surface area to the bed. This in-turn will offer more adhesion to the print bed. However, because rafts take a long time to print and use a lot of material, it is only recommended to use rafts for prints that have a low surface area with the print bed or that generally don’t have a good base will often benefit from a raft. Also, whether due to the design of the printer or calibration, those users with beds that are slightly uneven have often found that rafts can provide a good foundation.

Raft Extruder

Selects the extruder to be used for printing your Raft

Raft Layers

How many layers your raft will be. 

Raft Offset

How far away your part the raft will extend out to.