topic Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026 in AutoCAD Plant 3D Forum

Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

jiri.opalecky — Tue, 23 Sep 2025 16:01:56 GMT

Hello
I usually create component catalogs from STEP files, but today I started having a problem. When I create a component, a link is automatically inserted into all sizes, and when I start directing the component to the correct block, the blocks for all sizes are overwritten. It started today and is happening in both Spec Editor 2026 and on my other computer, where I have version 2025. Where is the problem?

@jiri.opalecky Your post title was modified to add the product name and version and to increase findability - CGBenner

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

CGBenner — Mon, 29 Sep 2025 13:43:53 GMT

@jiri.opalecky

Hello, do you still need help with this question?

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

rossler.conrado — Sat, 04 Oct 2025 18:57:44 GMT

I have the same issue, can´t find the solution.

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

jiri.opalecky — Mon, 27 Oct 2025 20:35:14 GMT

Hello

Hello,
This problem is still relevant for me. After discovering the problem, I purchased parametric libraries, which allowed me to work around the problem at that moment, but now I need to use a precisely prepared library based on step files for my project again, and I am unable to assemble the catalog element. When I enter a prepared block for one size, all sizes are overwritten.

Perhaps I am making a mistake, but I was able to create elements this way without any problems until August

Jiri

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

Michiel.Valcke — Mon, 27 Oct 2025 22:36:22 GMT

If I correctly understand, everything goes well up until PLANTPARTCONVERT, but when you map the blocks to individual sizes of your component in the catalog, each size mapping overwrites the previous size mappings?

If so, I can't reproduce the problem here. Are you able to share your .dwg file containing the imported step parts before using PLANTPARTCONVERT?

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

Michiel.Valcke — Thu, 30 Oct 2025 08:58:58 GMT

@jiri.opalecky @rossler.conrado
I recently became aware of another issue that sounds similar, but it should be limited to parts created in version 2026
https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Same-block-is-used-for-different-sizes-when-creating-block-based-components-with-AutoCAD-Plant-3D-Spec-Editor-2026.html

It is currently still under investigation

Even though you get the same behaviour in your other computer where you use 2025, you can try to make the part again from scratch in the 2025 version of the spec editor and see if you get the correct result.

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

gianni.bellu — Tue, 04 Nov 2025 08:39:33 GMT

Hello,

we have same problem, i find only this post about this

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

Michiel.Valcke — Wed, 05 Nov 2025 09:03:26 GMT

hi @gianni.bellu

Until Autodesk resolves the issue, you can install the 2025 version and create your components there. If you do, the problem should be avoided. You can still use a spec/catalog created in 2025 spec editor with a 2026 Plant 3D installation.

Re: Unable to define catalog components by size from STEP files - Plant 3D 2025 & 2026

lauri_barnhart — Mon, 10 Nov 2025 20:31:00 GMT

Hello, @gianni.bellu,

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