Hi there. I noticed that a lot of STLflix models and some other models get this weird bulges after slicing. It mostly happens it a model has some scratches/dents/metal texture. Any thoughts on the reasons? I was thinking on simplification but I am afraid that i will loose details. Ironing helps but just a little bit. And if you just go ahead and start printing as is, the nozzle will have some fraction and cause scary noises
UPD - Simplification and fixing didn’t help
P.S Can not share a model since it is a purchased one
Are you familiar with the term “Garbage in, Garbage out”?
That’s what you’re seeing here. If you have a model that has lots of corruption on the surface, the slicer will only magnify these shortcomings in design.
As an example, this sort of rough stair-stepping affect cannot be remedied in the slicer. You could try using adaptive
You could try adaptive/variable layer height function. This will vary the layers on the affected layers enabling you to print at let’s say 0.28 but vary it down to a layer height of 0.08 for smoothness where it counts. But note that it does it for everything at that layer height, not just for the section you want to remedy.
You may want to note if the model was intended for FDM printing or resin. I say that because when I first got into this, I downloaded a model that I could not for the life of me get to print well. Then I realized that this was because the model was intended for resin printers which have layer resolutions. FDM printers like Bambu typically have a layer resolution of 0.05 mm to 0.3 mm, while resin printers usually range from 0.025 mm to 0.1 mm. The smaller the better when it comes to details in a print.
To me, this looks like the model designer was going for a rustic/weathered appearance. You simply don’t have a lot of raw information to work with.
Another alternative is to convert the STL into a STEP file and bring it into CAD. From there you can reconstruct the artifact and modify specific sections.
If you’ve never worked in CAD, modifying an organic-like STL construct can be not only frustrating but futile.
Thanks Olias for a very detailed and extensive reply! Yes, this very model is intended for an SLA printer, yet I hoped I could just upscale it to 300% and call it a day. However, I have seen such defects on FDM models from STLflix (thankfully on just some parts and it could be mitigated by ironing, sanding and postprocessing). I will probably keep looking for a similar model, yet created for an FDM printer
Actually I found a way to print it, yet this method will not work with all models. I noticed that changing the orientation of the model reduces distortion, so I cut it into 4 pieces and also removed the top layer that had dented structure. It may not be the cleanest way to do so, however it will probably work