Skeinforge settings vs Great Rafts

In short: a raft is a printable, flat thick layer to even out your build platform. Through testing and whatnot your build platform takes a couple for the team and in time becoms uneven (holes, scars). The raft is there to make sure the build surface is flat, and also tries to assure good first layer adhesion to the platform.

My first rafts were thin candy string like threads that offered virtualy no support and actualy did the opposite of what it was supposed to do. The fatter base layers and the thinner support layer didn't assure first layer adhesion, except on very small builds.

A raft is important when you're printing with the standard build platform, and to a lesser extent when you're pinting on a heated build platform. Since printing with a heated build platform is very different from the standard, there's a separate post devoted to just that.

First off, i've learned through trial and error and many comments on the google makerbot operators group that the interface layer (thinner threaded 2nd raft layer) isn't necesary by default. If you learn how to make a nice fat spread base layer that's all you really need.

To get the raft you see here on the right, you need to manualy reposition the z-axis on the first line that's going down when the raft starts printing. Position your nozzle about 1mm above the build platform and start your print, then just lower the nozzle by hand untill your raft lines touch each other, but make sure they don't overlap. If the lines overlap you will see a very thin (like a hair) thread on top of the raft lines. That could mess up your first layer, but could also strip out your filament. By making such fat lines you could end up blocking the extrusion by feeding more into then the nozzle can lay down. So make sure the lines don't overlap. It'll take a couple of tries, so start out with a small raft to get the hang of it.