Structural framing (other) - Trimming automation fail

Hi Everyone, I’m new using Dynamo so please have this in mind,
I’m using a Revit plugin to automate steel framing modeling; the result is consistent in terms of geometry representation, which fits fabrication requirements. But for analytical purposes the model doesn’t fit the requitements because analytical vectors don’t have the right length, so when I export the model to structural analysis software’s it takes a lot of time to trim and adjust each vector line to compose nodes between vertical structural members (structural columns) and horizontal members (structural framing other – default family given by the plugin provider; not possible to change it given the embedded properties to automate fabrication process on different CNC machines).
On Dynamo, I already automate trimming adjustments for vertical members with success result. For horizontal members I did another graph with the same logic calling “Start Extension”; and “End Extension”; parameters, but when I run the script, changes are not made, the extension of the structural members doesn’t change, only change the arrows (extension arrows) position. Also, as you know it is not possible to manipulate parameters such as “Length”, “Cut Length” or “Reported length” given that they are OOTB “read only” parameters.

Does anyone have suggestions to fix this issue in Dynamo or with small changes on the family properties?

Thanks in advance for your recommendations!


Hi @RafaelSH ,

I think I follow, however it is quite hard to help you further without seeing (screenshots of) your Dynamo Graph, your Revit file (or a sample).

Also, could you maybe explain why the analytical vectors don’t match up with your actual structure? Or perhaps you could explain a bit more what the differences between the two methods are :slight_smile:

PS: I don’t really have a lot of experience with Structural Framing, so maybe the questions I am asking here are not the right ones.

I tried exactly the same thing and did not succedded to cut the framings. I think it is not possible. I did not find any node to do it. (Or python script)
I like to hear otherwise.

Hi Daan,
Thanks for your time; bellow you can find a better explanation:
As I said to automate steel framing modeling, I’m using a Revit plugin that also automate CNC codes that are going directly to different machines. When I use the plugin, the result is consistent in terms of geometry, because each stud, track or noggin has the proper length and position in relation with the panel.
To analyze a complete project, I must jump from Revit to other structural analysis softwares through IFC format. (Robot it is not useful in this case given the supported structural codes)
The issue is related to the steel framing plugin behavior; because all these plugins that automate steel framing modelling generates analytical vectors according to the length of each structural member. As you know to analyze those structures in structural softwares we must conform nodes and those nodes are not generated because horizontal and vertical analytical vectors are not matching.
So, the idea is to develop a Dynamo scrip to trim each analytical line to solve this problem.
I did two different graphs one for the vertical members (studs) and the other for the horizontal members (tracks and noggins) the first script it is working fine because it is possible to change parameter values and the geometrical result in Revit it is congruent; the second one it is not working because when I modify Start Extension”; and “End Extension”; parameters the result in Revit in terms of geometry it is the same, it is only changing the position of the grip arrows and not the structural member length.

For the vertical members it is working find for me but for horizontal members it is not working so I found a work around that it is not perfect, but it is a possibility. In resume I’m using horizontal elements did it by the plugin as a reference to model a new ones with the proper length and then I have to deled the old ones in order to send them as a analytical model to structural analisis software.