Preparing a structural model for 3D printing (geometry and slicing issues)  

RE: Preparing a structural model for 3D printing (geometry and slicing issues)

No images or videos attached to your post.  So its largely pointless.  Without being able to see anything its highly likely from your description that the model mesh is just too thin to meet any setting for extrusion width without using a smaller nozzle.  

The best way to get help is to slice in Prusa slicer like you would usually , get the problem and then use File>Save Project As from PS.  That will save a Prusa Slicer .3mf file  The PS 3mf will contain the objects and also just as important all the settings you are using to slice with.  We will be able to see exactly what you are working with and try possible solutions.

Also be aware that to attach files to the forum here you MUST zip them up or the forum will silently just not attach them.  The edit window is only a few minutes too so once you post it is best to double check your post actually has the items attached.  
This is likely whats happened to your previous post.  

RE:

Hi,

Thank you very much for explaining how attachments work here!

I’ll attach the ZIP files to this post so you can better understand what I’m working with.

For context, I’m using a Creality K1 Max with a 300×300 mm build plate and a 0.4 mm nozzle.

Thanks again for your time and support!

Slicer_video.mp4 Object_2.3mf Object_1.3mf img.8 img.7 img.6 img.5 img.4 img.3.heic img.2 img.1

RE: Preparing a structural model for 3D printing (geometry and slicing issues)

somehow, when you added the images, you included (Or the Forum Included) Formatting information, that prevented the images being displayed. 

I have removed the formatting. 
and now some images display. 
I hope this helps

Joan

RE: Preparing a structural model for 3D printing (geometry and slicing issues)

Hi Joan,

Thank you for the information!

I will upload all the files and images to a WeTransfer link and attach it as a reply to my initial post, so it will be easier for everyone to access everything properly.

RE: Preparing a structural model for 3D printing (geometry and slicing issues)

Posted by: @razvicu

Hi everyone,

I’m working on a project where I need to 3D print a steel structure of an industrial hall(img.4).The model was provided by the structural engineer in .ifc format. I opened it in Blender (using Bamboo) and exported it as .obj to make it easier to work with.

The model is extremely detailed. When I try to print it as a whole, it becomes way too small and complex for the printer, so I decided to split it into smaller pieces using Boolean operations in Blender(img.5).The issue is that no matter how small I make the pieces, many of them don’t show up at all when slicing (I’m using PrusaSlicer and printing on a Creality K1 Max).

I managed to get one part printed successfully by tweaking thickness settings directly in PrusaSlicer (img.1, img.2, img.3, video).However, the rest of the parts are not printable — the geometry is broken, most likely due to the initial export from ArchiCAD to IFC. Printable part previewed in Blender. The same part imported into PrusaSlicer.
https://storage.googleapis.com/prusa3d-content-prod-14e8-wordpress-forum-prod/2025/04/a8a49eab-slicer_video.mp4

Full structure model in Blender. Split segments of one floor in Blender.[

One problematic part in Blender.

The same part imported into PrusaSlicer. Slicing preview showing missing geometry.

In Blender I tried several fixes:

3D Print Toolbox → “Check All” and automatic repair

Mesh Cleanup → Fix Normals, Make Manifold, Decimate

Also tried Remove Doubles, Fill Holes, Solidify, etc.

But I still can’t get clean, slicer-visible, printable models.

I’ll also attach some more images to better show the issues(img.6, img.7, img.8).

My question is:How can I repair or prepare these models to make them 3D printable?

Is there a more reliable workflow when dealing with models coming from ArchiCAD → IFC → Blender?

Thanks a lot for any advice, tips, or workflow suggestions!(I’m also open to using different software if needed.)

You can find the ZIP file with all the images, video, and model files here: https://we.tl/t-vFrjkRenvg

The archive includes: images, a video, and Blender/3D files related to the issues I’m encountering.Below, I’ll leave a short explanation for each file so you can easily understand what you’re looking at:

Thanks a lot for any advice, tips, or workflow suggestions!

Img.1

Printable part previewed in Blender.

This is the model of the only part I managed to prepare properly for 3D printing. The geometry was visible and clean enough to process.

Img.2

The same part imported into PrusaSlicer.

After exporting from Blender, the model appears correctly in PrusaSlicer and is ready for slicing.

Img.3

Successfully printed part.

Final printed result of the only piece that was successfully prepared and printed. Other parts are not printable yet due to geometry issues.

Video

Slicing preview of the printable part.

A short video showing the sliced model in PrusaSlicer. As you can see, the object slices cleanly and is ready for printing.

Img.4

Full structure model in Blender.

This is the full industrial hall structure as received. Due to the model’s complexity and small details, printing the entire structure at once was not feasible.

Img.5

Split segments of one floor in Blender.

I divided the structure into smaller parts (using Boolean operations) to attempt printing each segment individually.

Img.6

One problematic part in Blender.

This is an example of a part after splitting. Despite appearing correct in Blender, it doesn’t slice properly.

Img.7

The same part imported into PrusaSlicer.

After exporting from Blender, the model appears correctly in PrusaSlicer and is ready for slicing.

Img.8

Slicing preview showing missing geometry.

After slicing, the model is either partially missing or completely absent, making it unprintable in its current state.

Object_1

This file shows the part of the structure that I successfully prepared and printed. After some adjustments in PrusaSlicer, the geometry was clean enough for slicing and printing without issues.

Object_2

This file shows an example of a part that I was unable to prepare for printing. Although it looks correct in Blender, it either doesn't appear or slices incorrectly in PrusaSlicer due to geometry problems.

Blend file

Full project file containing the entire structure.This Blender file includes the full imported model, the split segments, and the parts I attempted to prepare for 3D printing. It shows the complete workflow and the current state of the models before slicing.

RE: Preparing a structural model for 3D printing (geometry and slicing issues)

Thanks a lot for your help!

After recalculating the outward faces in Blender, there are now far fewer errors showing up in the slicer.

Also, for the piece where the geometry wasn’t appearing after slicing, I simply rotated it 180 degrees, and now it touches the bed completely.

From now on, I’ll start repairing the models manually based on the specific errors detected by the 3D Print Toolbox.

Thanks again for taking the time to help, it really made a big difference!