Frame generator custom / user structural sections driven length (G_L) parameter not fuctional

[RudolfVanDerSpuy]

I use aluminum extrusions, and have to make my own CCenter structural sections. I have no problem making and authorizing these. In an assembly I can select and open a part, and at .ipt part level the driven length in the parameter table is correct. The driven length "G_L" , has changed according to the needs of the frame. This value does not export correctly and displays the static value  of the pre-authorized  component when using in "Parts List" and "PartNumbers".  A super handy use of the driven length is to use G_L to export it and use as part of a PartNumber to ID parts. This works fine for all structural members native to the  original installed CC . With my custom stuff it does not export the driven G_L value of the members in a frame.Example: If I create Part Number {Member} & "x" {G_L}  the G_L part remains static My work around is to rename in Design Assistant. However it is counter productive to do so, and mistakes can happen. Working on INVENTOR 2025

[jan_priban]

Hello Rudolf,

basically all what you need is to include custom iProperty G_L into your part number formula.

These topics are related to G_L as well + my DOCX describing precision enclosed.

https://knowledge.autodesk.com/support/inventor/troubleshooting/caas/sfdcarticles/sfdcar[…]=42b67e83...

https://forums.autodesk.com/t5/inventor-forum/content-center-filename-part-number-length-precision-a...

Regards

Jan Priban, Autodesk

[RudolfVanDerSpuy]

Hi Jan

Thank you. This is what I have been doing. In a frame all the parts shows  part number with G_L as the original value, and not the generated length like yours. The only difference that I see is the brackets in your expression differs from mine. If i use <> it does not display a value in the part number, but text.

[RudolfVanDerSpuy]

Hi Jan

Try as I may, I cannot get G_L to export the driven length from these parts in a frame. Somehow G_L does not export properly, or CC does not read it properly. I seem to be missing something and I really cannot get to the bottom of it. I can formulate the part number to show B_L or anything other than G_L. G_L keeps displaying the original length of .ipt used to authorize and publish the family. If I understand  your answer to my original question, you used my .ipt and managed to publish it successfully. If so what an I doing wrong ?

[jan_priban · Accepted solution]

Hi Rudolf,

described in help here https://help.autodesk.com/view/INVNTOR/2025/ENU/?guid=GUID-9ED64200-A0CA-4F27-A308-9BF7ADB22D06

Yes, I published your aluminum square profile, it has G_L parameter exported to custom iProperty G_L and this custom G_L iProperty you need to reference in PartNumber as described in Help mentioned above. iProperty (PartNumber is iProperty) can reference other iProperty as G_L is in your / frame case

Use equal sing and G_L custom iProperty in square brackets

Jan Priban

[RudolfVanDerSpuy]

Hi Jan. Thank you very much. After your input I managed to sort out the problem. It is just amazing how all the video's and articles that I read explains everything except that one issue, and I just could not figure it out.