Shop Blog

Managing Moisture in your Materials

Nicholas Mendizabal 1 comment


Controlling the moisture content in your materials is an important part of obtaining a high quality extrusion. If moisture is not eliminated, polymer chains can weaken, diameter consistency suffers, and air bubbles can form in the filament as trapped water vapor expands when heated. Extruded filament that contains air bubbles will exhibit a signature 'popping' sound when the air pocket reaches the nozzle on your 3D printer, adversely affecting print quality.
 
Manufacturers take every measure to control the moisture content in their pellets at the point of production, but beyond that, the task of moisture removal is at the extrusion point. 
Different plastics absorb moisture at vastly different rates. Materials that readily absorb moisture from the air are referred to as hygroscopic materials. Materials that are resistant to ambient moisture are referred to as non-hygroscopic. Unfortunately, many of the materials that are used in 3D printing are hygroscopic, such as ABS, PLA, PETG, PC, and Nylon. It's important to consider the degree to which this is the case, as PLA, PETG, and Nylon are far more sensitive to moisture uptake than ABS.
A resin dryer is used to remove moisture from the materials that require it, and we have several here at Filabot that operate around the clock for this purpose. Once the material is dry, it should be used immediately or it should be stored in a suitable container with desiccant. Any air tight container will do. Out of an in-house need, we came up with our own solutions for polymer storage - a large stackable jug and a smaller container for additives.
The larger jug is made from HDPE, holds about 15 lbs of material, and features a 3D printed re-loadable desiccant cage and a label for notes and material ID. 

The smaller container for additives and colorants holds about 1 lb of material and also features a 3D printed re-loadable desiccant cage and a label on the rear.  
 

Comments

  • Stephen Brown October 25, 2016 | 09:33 PM

    Can pellets be dried without a resin dryer ie leaving them in a airtight container with a dessicant. Another Question: What exactly is a resin dryer and where can they be obtained? Steve in PA

Leave a comment