Wings 3D is a sophisticated open source subdivision modeler CAD software that's both powerful and simple to use. Skirt - This lets you draw a top level view around the perimeter of your printed object, this is a good idea because it begins the flow of plastic within the nozzle and helps prime before the print, it should all the time do that first, so you can also check if your bed peak is ready accurately and stop the print if it seems like it's not sticking well.
It is a very good thought to select layer heights that divide into even numbers of steps of your Z peak, having a miss-match of steps as the article builds is going to trigger issues - Just to clarify this - a 200 step motor using 16x micro-stepping gives you 3200 steps, an M8 threaded rod is 1.25mm per complete 3D Printed Stepper revolution so 3200/1.25 = 2560. In case you set a layer height of 0.32, that needs 819.2 steps - not a good variety of motor steps, so not best.
Alessandro is creating Slic3r in a short time so this guild may be a bit of outdated, however hopefully may still show you how to get started in case you are new to 3D printing, it's definitely the best route for an easy instrument-chain to great wanting prints. And as with each different 3D software-path generator you could have a calibrated extruder first earlier than you can get superior looking prints.
Top Tip - I might be interested if anyone else has noticed this - If you happen to start to see very, very fantastic 'hairs' of plastic on your printed components for no real purpose you possibly can think of, this can be a sign that your hot-finish is about fail, from build-up of laborious materials. My curiosity and fervour for 3D printing began in 2009 after visiting the RepRap project web site and studying a sequence of weblog posts by another extremely dedicated developer, Nophead.
A channel can be for instance a stepper motor pulse train, a PWM sign for a DC motor or a servo or a digital output pin. However stepper indicators are barely tough, as you want a precise variety of steps over the interval of the cue. You can do as much as about 30KHz alerts, up to 9 such in parallel, in addition to twenty-one thing binary outputs (e.g. for controlling the stepper direction, solenoids, or LEDs), with out ever missing a step jittering on the timing by as little as one CPU cycle. Here's somewhat (underground) video I shared a while in the past, demonstrating some early levels of the motor control library: