Why Are Horizontal Layer Lines Present on 3D Prints?

What’s Wrong with My Resin 3D Print?

When inspecting your 3D prints, you may notice visible horizontal layer lines across the surface of your prints.

What Causes the 3D Printing Issue?

Layer lines appear when a single layer fails to print properly, forming a clear visible horizontal line on the 3D print. This issue gets mixed up with the layer shifting, pixel lines, or stepper lines issue, however, each issue has a different root cause.

Layer lines are usually caused by one of the following or a combination of the following reasons:

Resin Profile Settings:

1. Normal layer exposure time is set incorrectly.
2. Lift height has not been set high enough.
3. The light-off delay time is not long enough.

Other Settings:

1. Pausing during the printing process.
2. Supports aren't strong enough.
3. Set up for hollowed print is incorrect.
4. FEP film needs to be replaced.

Troubleshooting the Layer Lines Issue

Resolving this issue may require adjusting several settings as well as redialing your resin before adjusting the supports. The following steps are in the order of the most likely cause of the layer lines:

Adjusting the Resin Profile Settings:

1. Check out our official resin profile and make sure you have dialed in the correct exposure time and lift height.
2. Make sure your light-off delay time is set according to this auto-calculator.

Other Adjustments:

1. Increase the Upper Diameter and Support Density. For suggested values, please refer to this article.
2. If it is a hollowed 3D model, make sure the wall thickness for small print is at least 1.5 mm, large print at least 2 mm, then add at least 2 drain holes that are at least 3 mm wide to the bottom of the 3D print.
3. Inspect the status of your FEP or PFA (nFEP) film and replace it if necessary.