How to make food-grade 3D printed models

You’ve probably noticed that we mention the food-safe properties of some filaments. And it’s true, there are several materials that can be considered food-safe, or food-grade to be specific (only certain manufacturers have proper certification), but it’s still necessary to coat the surface to make it truly safe for direct food contact. Let’s see why the surface coating is so important, how to add it properly, and what to avoid during the whole process.

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Important regulations

First, let’s talk about regulations: In Europe, there is regulation no. 10/2011 that summarizes safe and unsafe materials. In the USA this issue is covered by the FDA CFR 21 document. While there are many materials that are classified as food-grade, there are only a handful of manufacturers who have completed the rigorous and costly certification process. In general, certified materials are more expensive. If you need to make food-grade parts for your business, you will be interested mostly in materials with a valid certification.

Food-safe filaments

Let’s take a look at materials that are (not) suitable for direct contact with food. As we mentioned above, you can buy materials with food-grade certification (PLA by for example). But some filaments should be safe even without any certification, for example, PLA, PETG, or PP. On the other hand, some materials are rather unsafe and shouldn’t be used for direct food contact – for example, most ABS or ASA filaments. Unfortunately, it gets more complicated, because we need to take into account the pigments that are used to produce various materials. Even potentially safe filaments might contain unsafe pigments that might be dangerous when in direct contact with food. Therefore it’s good to ask a manufacturer about additives used, or use natural filament with no added coloring. Most of our PLA and PETG Prusaments (excluding PLA Army Green)* contain inorganic non-migratory pigments that should be safe, but keep in mind that we didn’t acquire any certification. If you print food-grade objects with our filaments, you should do it only for personal use, not for sale.

*Our coloring manufacturer confirmed that these colors should be safe for food contact: PLA Galaxy Black, PLA Galaxy Silver, PLA Azure Blue, PLA Lipstick Red, PLA Galaxy Purple, PLA Jet Black, PLA Prusa Orange, PLA Pineapple yellow, PLA Royal Blue, PLA Ms. Pink, PLA Opal Green, PLA Pearl mouse, PETG Jet Black, PETG Prusa Orange, PETG Signal White, PETG Carmine Red, PETG Yellow Gold, PETG Urban Grey, PETG Ultramarine Blue, PETG Galaxy Black, PETG Pistachio Green, and PETG Terracotta Light.

3D printer preparation

Once you select the right filament job, it’s time to prepare the printer. First, you need to keep it as clean as possible (outside and inside). You should try cold pull if you aren’t sure whether the extruder is clean enough. Then you should consider changing the brass nozzle for a hardened steel one: Brass nozzles might cause a health risk due to lead present in the alloy. Few sources also claim that it’s not wise to print with an extruder containing PTFE tube, due to Teflon toxicity at high temperatures. However, it releases only a small amount of toxic particles with temperatures exceeding 240°C and significant amounts with temperatures over 260°C. PTFE, therefore, poses no real danger if you print with PLA

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