Two-sided Image to STL

Launch Tool →
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Detailed Instructions

Choosing your images

  • The front image determines the object’s outer shape. Whatever silhouette your front design traces to becomes the final outline — the back is fit inside it, not the other way around.
  • PNG with transparency works best for clean background detection, though it’s optional — you can skip background removal entirely for either side.
  • Fewer, more distinct colors detect more reliably on both sides.

Background Removal

Optional and independent per side — remove it for the front, the back, both, or neither. If you skip it for a side, that side’s full original image is used as-is for color detection, which is useful if there’s no real background to strip out. A Detail slider per side controls the working resolution used for detection, separate from your final print size.

Color Detection

Detect colors separately for front and back. Click any swatch to fine-tune that color, or uncheck a color to leave it out of the export entirely.

Positioning the Back

Drag the back image directly, or use the Scale and X/Y offset fields for precise placement. The dashed outline shows the front’s actual computed shape. The mirror flip needed for correct two-sided printing is applied automatically at export — what you see is the back exactly as it’ll look when you flip the printed piece over.

Settings & Export

  • Core color — the piece’s structural middle layer. Defaults to your front’s dominant color, but you can pick any color — it’s independent of your actual front/back artwork colors.
  • Back background color — fills any part of the shape the back artwork doesn’t cover.
  • Print size — sets the longest side of the finished piece, in mm.

Click Generate & Download — you’ll get a ZIP with one STL per color. Load them together in your slicer and assign a filament color to each.