Lok3D

Bridge test for 3D printers

Generate a bridging test with spans from 5 to 120 mm and the length engraved next to each one. See how far your printer can span in mid-air without supports. Free.

  • Free
  • No sign-up
  • STL and 3MF
  • Millimeter precise
  • Runs in the browser
Example bridge test made with Lok3D

The model opens ready in the editor, in your browser. Then you can tweak anything and download STL or 3MF.

About the bridge test generator

A bridge is a section printed in mid-air between two supports, like the ceiling of a rectangular hole. The printer stretches filament from one side to the other, and the result depends on temperature, speed and fan.

This test prints bridges side by side, with growing spans, with the length engraved on the base. Tune your settings until the longest bridges come out straight.

What you can adjust

Growing spans

5 to 120 mm.

Step

5 to 20 mm between bridges.

Adjustable height

4 to 20 mm.

Engraved values

The span written next to each bridge.

Ideas for use

How it works

  1. Choose the spans (from, to, step) and height.
  2. Print as is, without supports.
  3. See up to which span the bridge stays straight.

How to print

Material
The same as the final parts
Layer height
0.2 mm
Fan
100% (PLA)
Supports
Never (that is the test)

FAQ

What span is good?

Well-tuned printers do 30 to 50 mm with PLA. Beyond that, results vary a lot.

The bridge sags in the middle.

Increase the fan, lower the temperature by 5 °C and reduce the bridge flow in the slicer.

Is it free?

Yes. The maker and the editor are free and run in your browser. Without an account, the project is kept for 48 hours; with a free account, it is kept in your account.

Which format do I download?

3MF (recommended: keeps colors and opens directly in Bambu Studio, OrcaSlicer and Creality Print), STL or OBJ, always in millimeters.

Create your bridge test now ↑

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