This page will serve as a guide of using Team 4099’s 3D printers effectively and safely.

Table of Contents

Introduction

Technologies

There are 2 commonly used technologies in 3D printing, called FDM (Fused Depisition Modeling), and SLA (Stereolithography). We currently utilize only FDM, of which we will get into more detail later. However, if you want to learn more about SLA technologies, check out the video linked here.

https://www.youtube.com/watch?v=_CISyU3D3WE

So how does FDM 3D printing work? FDM printers are the most common type of printer used. To summarize, FDM 3D printers work by laying down thin layers of plastic on top of each other, creating a part with height.

The way the plastic is extruded can vary between machines, but generally the plastic is fed through a spool, into a mechanism containing toothed gears. These gears grip the filament and feed it into the hot end, which is where the filament is melted. From there, the plastic leaves the nozzle, and cools.

Materials

• PLA – easiest to work with, low temp, doesn't warp much, low fumes. Not great with heat resistance.
• PETG – tougher and handles heat better than PLA, still fairly easy to print, good for functional parts.
• PET-CF (carbon-fiber PETG) – stiffer and stronger than plain PETG, great for structural/functional robot parts. It's abrasive, so it needs a hardened steel nozzle, not brass. Prints hotter and is picky about moisture, so keep it sealed.

All filament absorbs moisture over time — an old or open spool can start popping, stringing, or printing weak, especially PET-CF. Keep spools sealed with desiccant when not in use.

Procedures

To get started with 3D printing, there are a couple of steps that have to take place.

Bed Leveling

The nozzle-to-bed distance needs to be consistent across the whole plate for good first-layer adhesion. Most of our current printers (Creality, Bambu) have some form of assisted or automatic leveling — run it before a print if the printer hasn't been leveled in a while, or if the last print had adhesion issues. As a rough guide, check every few weeks to about once a month for a printer in regular use. Turn on calibration for the first print after youve turned off the machine or if anything seems wrong.

Slicing