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3D Printing

A guide for PPLD's 3D printers

Contact the Makerspaces

Library 21c: 
    (719) 531-6333 x1549

East Library: 
    (719) 531-6333  x1372

Sand Creek Library: 
    (719) 531-6333 x7018

Manitou Springs Library: 
    (719) 531-6333 x7004

Troubleshooting Common 3D Printer Issues

This section offers some basic troubleshooting tips for 3D printing.

If you encounter persistent issues, or if resolving an issue involves adjusting settings on the 3D printer or utilizing additional tools, please let staff know so they can assist you.

It is always recommended to double-check the Print Settings section of PrusaSlicer if you encounter an issue with a 3D print.

Material Settings

One of the most common and easy-to-make errors is failing to select the correct material from the dropdown menu in PrusaSlicer.

If the first layer is not adhering to the bed or if nothing is extruding from the nozzle, this should be checked first. 

Always make sure that the selected material matches the one loaded into the extruder.


Enabling Supports

Another frequent issue is forgetting to select one of the support options under from the Print Settings section. If overhanging areas of the print are failing, this may be the reason.


After slicing your 3D model in PrusaSlicer, if you haven't selected supports, be sure to check the bottom right corner of the screen for a warning message. This message will indicate if the software has detected overhangs which may require supports for proper printing.

In the sliced preview, overhangs are indicated by the color blue.

While PrusaSlicer can automatically repair many common issues with 3D models, you may encounter occasional problems that the software cannot resolve.

Parts Too Thin to Print


If a 3D model appears fine when viewed in the 3D Editor View in PrusaSlicer, but certain parts of the model are missing in the sliced Preview view, it's possible that those parts are too thin to print.. On our Prusa printers, the minimum size for vertical perimeters is about .3mm.


One solution is to scale the entire model to a larger size in PrusaSlicer until all parts are large enough to appear in the sliced Preview view. 

If scaling the whole model up is not option, you may need to bring the file into a modeling program to edit the parts that need to be thicker.


Non-Manifold / Holes in Mesh

This Sculpteo page defines non-manifold objects in the following way:

 "Without getting very technical, non-manifold geometry is a geometry that cannot exist in the real world. Meaning that a 3D model can be represented digitally, but there is no geometry in the real world that could physically support it. Since the mesh of the 3D model is defined by edges, faces, and vertices, it has to be manifold. If it is a non-manifold mesh, it means there are errors in the 3D model that cannot define with precision the geometry of the 3D model."

Image courtesy of Sculpteo

Non-Manifold also refers to objects, like the one below, which have holes in the mesh. Since the walls of the mesh do not have a defined thickness, the holes make it so the object cannot exist in the real world. Repairing these holes can be done automatically in PrusaSlicer, but depending on the model, it may sometimes be preferable to repair holes in a separate software.

Image courtesy of 3D Hubs

File Size Too Large

Another issue happens when trying to work with a very large file into PrusaSlicer. This can cause PrusaSlicer to run slowly, and potentially lengthen the printing time.

As explained by 3D Hub: "A mesh is 'over-refined' when the total number of triangles of the STL mesh is larger than required. This will not lead to any errors during 3D printing, but it will unnecessarily increase the size of the STL file, making it more difficult to handle. Usually, the tiny details that are represented by an over-refined mesh cannot be 3D printed, as they exceed the capabilities of most systems (in terms of accuracy and minimum feature size)."

PrusaSlicer has a built in feature, called Simplify model that can directly reduce the triangle count of any STL file. However, it may sometimes be preferable to simplify the model in a program like Blender, where you will have more options for fine tuning the model.


Image courtesy of Pinshape

Flipped / Reversed Normals

This LulzBot tutorial explains reversed normals in the following way:

"Every plane composing each shell of a 3D model has an intended inside and an outside, called a 'normal.' When a plane’s orientation is reversed in relation to those around it, it’s referred to as a 'reversed normal.' This becomes an issue when it occurs unintentionally within a model, and ranges from a tiny section of a shell, to intersecting shells of a complex multi-shell model, to an entire model with a single shell that is all reversed.

Reversed normals in the sphere on the side of the cylinder have caused inaccurate slicing that creates an unintended void."


It is always recommended to double check the Print Settings section of PrusaSlicer if there is an issue with a 3D print

First Layer Too Squished or Not Adhering

If the first layer of the print is either starting too close to the bed (layer will look very thin and squished) or too high from the bed (may not be adhering to bed at all) you will want to stop the print immediately.

Usually, all that is needed is to restart the print so that it can run through the auto-leveling sequence again.

If restarting does not fix the issue, please notify staff.

 Image courtesy of Prusa


Corners Warping / Curling

Photo courtesy of Simplify 3D

Warping occurs on prints because plastic, shrinks as it cools. For more details, check out this page from Simplify 3D. This is especially noticeable for larger prints. It is recommended to turn on Brim in PrusaSlicer to help increase the surface area of the print which in turns helps hold it to the bed. Residue on the 3D printer bed can also contribute to warping, so it is important to make sure the bed is cleaned regularly.

Print Coming Off Bed

A similar issue is prints coming unstuck from the printer bed completely during printing as seen in the photo below.

This is more common when trying to print multiple pieces or tall, narrow objects. Like warping, making sure the 3D printer bed is clean and using a brim during printing may help prevent this from occurring.

Filament Tangled

Most often, the cause of a bad-looking print (layer shifting, delamination, etc.) is that the filament has gotten tangled, 

When you're putting filament away, make sure to wrap it snugly and lock it into place with the holes on the outside of the spool.

Image courtesy of MatterHackers

Visit this post from ALL3DP to learn more about how tangles are formed. Please notify staff for assistance if filament is tangled.

Other Quality Issues

For more specific print quality issues, check out this troubleshooting guide from Prusa.

Prusa Parts Explained