How to Prepare Your CAD Files for a 3D Printing Quote
Poorly prepared files lead to delays, reprints, and wasted money. Follow these steps before sending your files to any service bureau.
File preparation is where most prototype projects go wrong. Here's how to get it right before you reach out to a service bureau.
Export as STL or STEP
Most bureaus prefer STL (for direct print jobs) or STEP/STP (for review and potential modifications). Check with your bureau — many now accept native formats like SolidWorks .SLDPRT or Fusion 360 .f3d.
Check for Manifold Geometry
Your solid must be "watertight" — no holes, non-manifold edges, or inverted normals. Use tools like Meshmixer, Netfabb, or your CAD software's built-in repair utilities.
Set the Right Resolution
For STL exports, use a chord tolerance of 0.01mm or better. Low-resolution STLs produce faceted surfaces that show up in the final part.
Specify Units and Scale
Always confirm units (mm vs inches) when exporting. A misread unit can result in a part that's 25x too large or too small.
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