Arc Fitting Only Works on External Perimeters

[CCS86]

Bambu Studio Version

1.7.7.89

Where is the application from?

Bambu Lab github releases

OS version

Win 10 x64

Additional system information

No response

Printer

X1C

How to reproduce

Slice a model of a cylindrical tube and look at the g-code output for external and internal perimeters.

Actual results

In trying to diagnose why a mostly cylindrical print sounded smooth on some perimeter loops, and sounded very grunty on others, I noticed the arc fitting is only being applied to external perimeters, and even perfectly circular internal perimeters are still interpolated with G1 moves. This is true on both classic and arachne engines.

Expected results

Why not fit arcs everywhere (besides slicing time)? At least give us the option so the printer runs more smoothly and more quietly. Plus, internal perimeter artifacts will print through to external perimeters.

Project file & Debug log uploads

Cylinder.zip

Checklist of files to include

• [X] Log file
• [X] Project file

[CCS86]

Any updates on this @QingZhangBambu ?

[QingZhangBambu]

the result of arc fitting depends on the arc angles, so sometimes it may not work. I will check this and try to solve it.

[CCS86]

I definitely understand the inter-segment angle limitation, but that isn't what is going on here.

This is happening on both BS generated primitive cylinders and on very fine STLs. These models all get arcs robustly generated on external perimeters, but never on internal perimeters.

[QingZhangBambu]

I'll check out the arc fitting process, it might be a little delayed since we're updating to the 1.8 beta version.

[CCS86]

Hi @QingZhangBambu , any updates on this?

[BambulabRobot]

This issue has been marked as inactive due to no response for 90 days.

[CCS86]

Bump

[SaltWei]

@QingZhangBambu Bump