3D Printing Bridge Calibration Test (Basic & Advanced)

🎥 Watch the video tutorial

In the video, I explain:

-How bridge flow and speed affect the print.

-Why more flow gives smoother results.

-How to tune these settings in OrcaSlicer.

-How to combine this with Tree Supports → “Critical regions only” to skip supports in bridges automatically.

🧩 About this model

This is a bridge calibration test designed to help you fine-tune the flow, speed, and cooling parameters of your 3D printer for perfect bridges — no supports needed.

You’ll find two STL files included:

BRIDGE CALIBRATION.stl → Simple version for short bridges (perfect for initial tests).

ADVANCED BRIDGE CALIBRATION.stl → To push your settings further.

Both files let you test different Bridge Flow Ratios (1.0 / 1.5 / 2.0) and Bridge Speeds (25 / 15 / 10 mm/s).
You can print them one after another and easily see which combination gives the best results on your printer.

🔧 Recommended settings

These values are what worked best for me on a FlashForge AD5X with a 0.6 mm nozzle.

🧠 Why this test matters

Most slicers are tuned for printing on solid layers, but bridges behave differently — there’s nothing underneath, so the filament doesn’t get squished or widen as usual.
That’s why increasing the bridge flow often gives better results: wider lines that touch each other and stay straight in the air.
Combining that with lower speed and maximum cooling produces clean, smooth bridges without sagging.

💡 Notes

You can download both STLs and print them separately.

For faster comparisons, print at 1 wall / 10 % infill.

Share your results — I’d love to see how your bridges turn out!

🌐 More resources

📘 Complete Fusion 360 Course (in Spanish):
👉 https://knincustom.com/pages/cursos

📺 Find us on YouTube:
👉 https://www.youtube.com/@KNIN_Custom