{"id":40,"date":"2018-12-09T05:11:59","date_gmt":"2018-12-09T05:11:59","guid":{"rendered":"http:\/\/fenneclabs.net\/?p=40"},"modified":"2018-12-11T13:22:42","modified_gmt":"2018-12-11T13:22:42","slug":"3d-printing-transparent-parts-using-fdm-fff-printer","status":"publish","type":"post","link":"https:\/\/fenneclabs.net\/index.php\/2018\/12\/09\/3d-printing-transparent-parts-using-fdm-fff-printer\/","title":{"rendered":"3D Printing Transparent Parts Using FDM\/FFF Printer"},"content":{"rendered":"

Ever since I got my 3D printer, I have been wondering whether it was possible to produce transparent parts. While there are plenty of transparent filaments sold on the market, they typically do not produce transparent prints, but rather translucent ones.<\/p>\n

The difference between transparency and translucency is in the material’s tendency to diffuse light.\u00a0\u00a0Diffusion may result from several factors, the most dominant one in our case is the inhomogeneity of the print. Under normal settings, the printer leaves small cavities (bubbles) inside the print. Each cavity acts as a small lens (as it is curved) and scatters the light passing through, obscuring any image standing behind the print and making it… translucent!<\/p>\n

Having in mind that the plastic itself is inherently transparent and that bubbles from the printing process are the only thing preventing us from achieving optically clear prints, I began searching for the right print setting to accomplish the task.<\/p>\n

I started by\u00a0searching the internet for prior attempts,\u00a0but all I could find was\u00a0this<\/a> YouTube video. It was a great start, but I wanted to achieve clearer results.<\/span><\/p>\n

Let’s Start<\/h1>\n

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In short, the basic settings using CURA are:<\/p>\n

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CURA settings for transparent parts<\/figcaption><\/figure>\n
    \n
  • Layer Height:\u00a0\u00a0\u00a0 0.05 mm<\/li>\n
  • Infill Density:\u00a0\u00a0\u00a0 100%<\/li>\n
  • Infill overlap percentage:\u00a0\u00a0\u00a0 6%<\/li>\n
  • Flow:\u00a0\u00a0\u00a0 108%<\/li>\n
  • Print Speed:\u00a0\u00a0\u00a0 24 mm\/s<\/li>\n
  • Enable Print Cooling:\u00a0\u00a0\u00a0 OFF<\/li>\n
  • Printing Temperature:\u00a0\u00a0\u00a0 255 \u00b0C\u00a0 (on the highest end of the recommended range, I was using prusa’s ABS)<\/li>\n
  • Build Plate Temperature:\u00a0\u00a0\u00a0 100 \u00b0C<\/li>\n
  • Nozzle Diameter: 0.4mm<\/li>\n
  • <\/li>\n<\/ul>\n
    \"\"
    Infill overlap (percentage)<\/figcaption><\/figure>\n

    The main purpose of the setting above is to make the laid plastic’s consistency as thin as possible by heating it to the highest possible temperature, and then forcing it into the grooves of the previous layer by applying over-extrusion (flow > 100%).<\/p>\n

    (I found it especially difficult to eliminate bubbles at the interface between the infill and the outer wall. To deal with this I changed the infill overlap).<\/p>\n

    Before printing, make sure that the hotend is clean, as leftover material in the part can damage its purity. After the first layer has been laid down, the hotend must be as close to the build plate as possible, but not too close as it might get clogged or even scratch the build plate. To find the sweet spot, I found it best to adjust the “live Z” (on prusa MK3\/2) to the point where the air gap between the tip of the hotend and the build plate just disappears. This rule of thumb ensures that the plastic is forced into any gaps between the first layer lines and the build plate.<\/p>\n

    Post-Processing<\/h1>\n

    The down-side of over-extrusion can be seen in the video below, in which a “plano-convex spherical lens” (flat on one side, and curved on the other) is being printed. Notice that the hotend is scraping the last layer, and is pushing on a chunk of excess material resulting from over-extrusion. The chunk is more pronounced on the first layers and typically ends up on the surface of the model. Worry not, as it can be easily removed with a crafting knife.<\/span><\/p>\n