Bridging

Also known as: Bridge, Bridging Test

intermediate Techniques

Printing horizontal spans between two points with no support underneath.

Bridging is printing a horizontal (or near-horizontal) span between two anchor points with nothing but air underneath.

How Bridging Works

  1. Filament is extruded in mid-air
  2. It’s pulled taut between anchor points
  3. Cooling fan solidifies it quickly
  4. Result: a self-supporting span

Bridging Success Factors

Cooling

  • Maximum cooling for bridges
  • Solidify before sagging

Speed

  • Moderate speed works best
  • Too slow: sags
  • Too fast: pulls off anchor

Temperature

  • Lower end of range
  • Faster solidification

Distance

  • Shorter bridges = better results
  • Most printers: ~50mm reliably
  • Good cooling: 100mm+ possible

Slicer Settings

Most slicers have specific bridge settings:

  • Bridge Flow - Often reduced (90-95%)
  • Bridge Speed - Moderate (20-40mm/s)
  • Bridge Fan - Maximum (100%)

When to Use Supports Instead

  • Bridges longer than your printer can handle
  • Sagging is unacceptable
  • Complex multi-direction bridges

Testing

Print a bridging test to find your printer’s limits. Many test models available online.