# Need help to create 3D model from 2D

Coreform Cubit Version: 2024.3
Platform: Windows

Issue Not sure how to accomplish basic tasks or how to approach the problem
I am brand new user and never used Coreform before, so i apologize if my question is very simple.

What can we help with?

I have a legacy 2D earth model stored in Cubit format, with dimensions approximately 18km (X) by 4km (Z). Visually it looks like surfaces (~450 of them) but in a model tree it shows as “Sheet bodies” I aim to perform some fundamental manipulations to transform it into a 3D model/mesh suitable for Finite Element Analysis (FEA).

1. Selecting a Region:
As a brand new user with no prior experience with Coreform, I’m looking to isolate a specific portion of the 2D model by limiting its X-range to approximately 4km. I apologize if this question seems basic, but any guidance or methods for accomplishing this task would be greatly appreciated.

2. Creating a 3D Object:
Once I have the desired 4x4km segment of the 2D model (where all Y coordinates are 0), my next step is to extrude or translate it in the Y direction, preferably by 2-3km, to generate a 3D object. However, as a newcomer to Coreform, I’m unsure about the most effective method to accomplish this transformation.

3. Mesh Generation:
With the 3D object/volume in hand, the final step is to generate a mesh while ensuring control over the mesh size in the Y direction, aiming for consistency with the mesh size in the XZ plane, which ranges from approximately 1 to 100 meters.

I would greatly appreciate any suggestions, recommended resources, or step-by-step tutorials available online to help me achieve this task effectively.

Hello @CM2024,
the easiest way would be to cut your region out and then create some volumes with the surfaces.

Here is a quick example how you could do it.

As i don’t have your geometry i will create one.

``````#!cubit
reset
create surface rectangle width 18e3 height 4e3 yplane
#!python
xl = 18e3
cuts = 20
for i in range(cuts):
cubit.cmd(f"webcut body all with plane xplane offset {xl/cuts * (i+1)-xl/2} rotate 60 about y center 0 0 0")
cubit.cmd(f"webcut body all with plane xplane offset {xl/cuts * (i+1)-xl/2} rotate -60 about y center 0 0 0")
print("webcuts done")
``````

We can perform webcuts to get our desired region and delete the rest afterwards.

``````#!cubit
webcut body all with plane xplane offset -2e3
webcut body all with plane xplane offset 2e3
delete body all with x_coord < -2e3
delete body all with x_coord > 2e3
``````

Then we will sweep the surfaces in y to get the desired volumes.

``````sweep surface all vector 0 1 0  distance 2e3
``````

The next thing is to do the imprint and merge. We will set a mesh size and even can set our desired element size in the y direction. Mesh.

``````imprint vol all
merge vol all
vol all size 200
curve all with y_coord > 5e2 and y_coord < 1.9e3 size 500
curve all with y_coord > 5e2 and y_coord < 1.9e3 scheme equal
mesh vol all
``````

@Norbert_Hofbauer Thank you very much for quick response !
Script worked as expected, but because of the particular geometries , mesh quality is not great (see attached image).
My next challenge is to try to overcome it.
For initial FEA I do not need all the small details, so i was hoping to merge some of the small surfaces in 2D before using sweep command.

2d_small.sat (1.3 MB)
Which command would be the best for merging set of surfaces into one surface ?

I attached file with 2D geometries as well.

Thank you very much in advance

I found from the GUI Geometry → Unite helps with merging surface
cubit command > unite surface ID1 ID2

and power tool with diagnostics helps to identify small curves and surfaces

and wondering if there what is a cubit command to the similar statistics ?

I am very new to Coreform and trying to learn, so i apologize if some of my questions are too simple

You can query such info with the python api.

https://coreform.com/cubit_help/cubithelp.htm#t=python%2Fnamespace_cubit_interface.htm