STEP import

I haven’t been able to reproduce the issue. You can send me link to problematic STEP files through private message or email. I also don’t know what you’re trying to achieve and what is your exact process. Did it import exactly like that or are you running modifiers or doing some other processing?

I will of course try to see if I can reproduce this issue, but I can’t promise a fix in near future without further information and data.

Are you able to check the data? Import the step file back into your software? I’m guessing it’s the model. I am using STEPPER for 2 reasons: It keeps orientation from parts and keeps them instanced, and the mesh is actually merged.
Data from Rhino mesh is not. Exported data from keyshot is hit or miss, plus the time to import there is a pain.

Is there a good trick to editing the mesh after you’ve imported and settled on mesh quality?
I think I have it right, but I wonder if I’m missing something.

Clear custom split normals.
Shade Smooth
Clear Sharp Edges
Change Auto Smooth angle to something more like 15-60, depending on mesh settings, then add sharp edges if needed
And if I’m going to edit it, and it’s not going to be deformed,Then I’ll usually run a mesh cleanup > limited dissolve at an angle around .05 or so for really high quality mesh, or .1 for lower quality.
And finally a quick Alt+J just to get rid of a few extra triangles.
The limited dissolve can end up creating some funky geometry though, so you sometimes need to a add weighted normal modifier (check keep sharp if you’ve added some of those)

Sometimes, seemingly randomly, I still end up with really faceted shading. Am I missing a step?

Been about 6 months, so I thought I should check in on this. Tried the 1.1 rc2…

I really like that you can change detail after the import! One slider, super easy (although I must confess that I’d like a good old “maximum surface distance tolerance” so I can relate to real world measurements, but I completely get that the slider solution is more intuitive). :+1:

(EDIT: A coworker just told me he really likes the three different detail options you get in Datasmith, and that he uses “limit maximum edge length” especially… something to keep in mind, perhaps.)

However, the automatic merging of solid objects is still a very bad default setting. No matter what I import, I get two objects: One big lump with all solids and one big lump with all surfaces. Any assembly hierarchy is completely ruined, which means objects will have to be manually separated for material assignments and pivot points have to be re-created for animation (also, object names removed, although that may still happen depending on which CAD software you are exporting from), which wastes a lot of time re-doing things that you don’t have to do using other methods.

(EDIT: I just noticed that not only are solids lumped together, they are even merged together! In other words: The import performs boolean operations without asking the user and alters the geometry! You can’t even easily revert it manually. 110% major, major showstopper.)

My current goal at work is to dump 3D Studio Max/Keyshot at work, so I’m still crossing my fingers for this, but right now, Unreal Engine are doing great strides in this area, with native STEP importing, raytracing (even offline) and really powerful animation tools so they’re currently winning this race (and yes, I get that it’s not a fair comparison, or even a race, but that’s the lens I’m viewing this through)…

…however, if we can retain individual objects, and still be able to select them and adjust detail on the fly, I can see a future where this workflow could be faster than the Datasmith/Dataprep one. :+1:

(EDIT: One final bit of testing… it takes a looong time to import things. I’m waiting for the past 5 minutes now for something that Rhino imported & exported in under a minute… if I want to render in Blender today, going via Rhino/Unreal is still faster, even if you include application load times.)

You Can get something closer. The default option is the “artist friendly” number that doesn’t really Mean anything, so to me it’s not really friendly at all bit it might be to some. I feel like, if you’re using blender, you’re not that kind of artist. But the other option, angle is in radians, which goes a Little far in the other direction. But the other number is what you’re after.
STEP format Usually would assume CAD workflows with parts. Each part would be their own definition, and then assembled, which could be a sub-assembly several times as well. This is where STEPper really shines because all of those parts keep orientation, origin, and instances (assuming the items started on some normal defined datum in the first place. Sometimes they are dropped in place, and then the origins suck.
Where it really falls short, is the designer workflow, which I’m guessing you are based on the software packages. Creating models from Rhino, for instance, and importing with STEPper, it’s not great. Even if I try and define everything as block instances there, it just doesn’t seem to work the same. So I get the same. Things are just clumped together in 2 groups. Solids, and surfaces.
It works great from SolidWorks models, assuming you put models together as assemblies rather than just making one giant mess of a part, like some designers do. And the few Creo models I’ve tried also worked well.
But if the data had been a mess, I use the 3dm importer instead, which uses the Rhino mesh, just like keyshot does. Also, I’ve used keyshot to mesh things as well, but obviously neither of those options are free or low cost. And the mesh from both of those needs Serious cleanup. Once cleaned up though, it has some advantages. The cascade mesh method causes a Lot of odd meshes where it collapses bits in the middle of a big surface without a great way to fix them. OR you mesh the Hell out of the model, then reduce it later. It works great for organic models, but for hard surface models with a mix of fillet sizes, you’ll have great looking mesh on a fillet, and then the corner is garbage. And if you have a curved trim, you’ll See the cascade effect, as you get further from that edge, you’ll see the same shape repeat and sort of dissolve as it gets further from that edge. So not the most uniform geometry.
One thing to watch out for with UnReal is DataSmith. Their license Says that it will be charging for it. They just haven’t yet? But if they get a tool that really works well for designers without much of a technical knowledge, be ready to pay.

I used 1.1_rc2 on my “old” Windows 10 installation, can’t rememnber which blender and Python version. I switched to Windows 11 with blender 2.95.5 and Python 3.9.2, but I get the error “DLL load failed while importing _BRep”. Could someone help me?

Ok, tried “STEPper_1.0_for_Blender_version_2.93_or_later” and it works. But: I don’t get seperated parts as it used to be.

I tried Blender 3.1.0 Alpha with Stepper 1.1 rc2 downloaded from Gumroad, and it works as it should. Just make sure before you install anything the previous Stepper folder is removed from the addon folder. If there’s an error during installation it doesn’t remove the faulty installation automatically. Also I can’t find Blender 2.95.5 on blender.org so I can’t test it.

The geometry is imported as it comes from the library, I’m likely able to add some more granularity in the future to separate the objects, however complex full compatibility with proprietary workflows that may break the spec are really out of my hands. Also something like fusing faces or not is possible to add as an option.

Sorry, I meant 2.93.6. The last “official” (non aplha or beta) one.

I tried 2.93.6 the Steam version on Windows 10. Works as expected. Windows 11 is currently not supported and might do some DLL signing that is not available on Windows 10, so if you can, you should probably try and disable anything like that if the problem persists and try again. Also remember to install Microsoft Visual C Runtimes, if they are missing. https://docs.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist

If you mean the spec of STEP, then complete assemblies are fully supported and have been for literally decades. The library you use must surely include it, otherwise it’s a very surprising and incomplete one…

(Same for colored objects.)

Hi! Any news on this? Have you done any progress to import the colours of the Step file. It would be a great improvement for the workflow. Kind Regards!

Hi there, I switched from windows 10 to 11 and the importer does not work any more.
You suggest that there is something one may try to bypass the “DLL signing stuff”, can you provide some more info or a link to a guide? thank you very much! I need to import a STEP file but I do not have any windows 10 machine at the moment.
Thank you for the great addon and for your help.
(my setup: windows 11 (…) blender current official release 2.93.6 and STEPper 1.0; microsoft VC stuff installed)

Ambi - the nature of this thread is that, naturally, all you’re seeing is people having problems. What you won’t see is the many happy users whose lives your work is making happier.

Just finished another job where I modelled in Solidworks and brought things across to Blender for rigging, animation and rendering. Solidworks was the usual PITA its owners have come to love/hate. Blender was, well, blender - did a great job once I’d learned Python and munted a bunch of other plugins to behave.

The one utterly painless step in the process? Getting my STEP files outta Solidworks and into Blender.

So I thought it was about time to pepper the thread with a “thank you”.

If I sound like a fanboi, it’s probably because I am one. You’ve done some great work here. Keep it up!

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Indeed, without this plugin making product animations would be 100 times hadrer!