Roadmap to extrusion success

Good filament can only be produced after following a specific sequence of steps. We condensed these steps into a short timeline.

The article 3 keys to successful extrusion forms the basis for context and perspective, we recommend to read it before continuing.

Now, let’s see what hands-on roadmap can be defined to achieve success.

Step 1: Prepare the parts

This step only applies to recycling projects, and can otherwise be skipped.

The regrind you will feed in the extruder needs to be free of any :

  • Glue
  • Dust
  • Foreign plastics (please make sure your batch was collected/sorted very well)
  • Any other impurities in general (solid or liquid)

In general, it is easier to clean the parts before shredding them.

You might need to pre-cut your parts to feed them in the Shr3d It or GP20.

Step 2: Shred

This step only applies to recycling projects, and can otherwise be skipped.

After shredding, particles should be smaller than 4mm.

Step 3: Dry

This step only applies to hygroscopic polymers (which absorb moisture). It can be skipped when working with hydrophobic materials.

Most polymers absorb moisture, which can cause major issues during extrusion. It is good to dry 1.5-2kg of material at once, so that you do not run out in the middle of the experiment. The drying conditions (temperature, duration) depend on the material, and can often be found on their Technical Datasheet.

Step 4: Start logging data

Logging all your experiments is essential. The Filament Maker does not record any data automatically (aside from the settings you apply).

This guide explains how to start logging data with DevoVision.

Starting a datalog resets the Filament Maker. It is recommended to start logging at the very beginning of your extrusion session – not when plastic is flowing.

Step 5: Pre-heat & transition

The barrel of the Filament Maker never runs empty.

When you stop feeding, it stops pushing.

The key is to choose a starting temperature which will ensure the full melting of the material you want to feed, as well as the material which was left inside the barrel at the end of the previous session.
It is important to know the melting ranges of both. They must overlap. If not, you will need to choose an intermediary transition material (typically Devoclean MidTemp EZ or Devoclean HighTemp).

How to choose the right starting temperature ?

The first time you use the Filament Maker, it will be full of PLA (range = 170-220°C approx)
As soon as you start processing other materials, you will most likely end each session with Devoclean MidTemp EZ (range = 190-300°C approx).

When processing a brand new material for the first time, it is wiser to overestimate its melting range (typically 20% above its melting temperature, or 150°C above its glass transition temperature).

When transitioning between 2 materials, please make sure the hopper is 100% empty before feeding the next material. Not a single particle should be visible in the feeding area.

Step 6: Troubleshoot

Melting all the material is a good first step, but the true challenge is to achieve good filament quality.

The obvious issues are the ones you can see with the naked eye. In general, they are easy to notice, understand, and fix.

Please feel free to consult our dedicated section. The objective is to achieve a material flow that you can pull into medium-quality filament for 30-60min without any major incidents.

The most common extrusion issue (thickness deviation) is a lot more difficult to manage, and time-consuming. It will be the focus of the next step: finetuning.

Step 7: Finetune

We wrote an entire filament consistency guide on the topic.

The objective is to control the thickness tolerance, which is directly connected to the flow stability. Here, we assume that the most severe/obvious issues have been taken care of (bubbles, major clogging, feeding problems….).

Every single aspect of the entire process must be controled in order to achieve a good tolerance.

Step 8: Spool

That’s right. Spooling only comes as the 8th step.

Because spooling the filament during the adjustment phases might disturb the results (and the filament wouldn’t be printable anyway!).

The spool must collect the nice filament pulled by the roller, not too tighly nor too loosely. Before starting the assistant in the spooling menu, the dimensions of the spools and the positioner must be calibrated. By default, the dimensions are those of 3devo’s standard spools.

Step 9: Purge

99% of the materials shall not be left inside the barrel during shutdown.

In order to avoid damaging the equipment severely and/or spend days trying to achieve good results again, we strongly recommend you purge the Filament Maker at the end of each extrusion session. Every time, even when you plan on extruding the same material the next day.

Please have a thorough look at our purging guide.

Step 10: 3D print

Just like extrusion settings, the printing settings should be finetuned specifically for each grade of material. Two different PLAs might require different settings.

This is a research step in its own right.

Please feel free to experiment with your printer and slicer.

This website may come in handy