How to create Frustum in DXF format for Autocad?

Question

I am trying to create a frustum using DXF file with my text editor, but unable to find any good solution or way to create it. If anyone knows and would be obliged to help me find a solution DXF file or an example, that would be a great help. Thank You

Answer 1

A frustum is a 3-dimensional figure. While the DXF file format does contain provisions for coordinates in the Z-direction(3rd dimension), you cannot use it to define a true solid model. There are 3DFACE and 3DSOLID entities available, but they do not give you solid model objects like the IGES or STEP file formats would.

That being said, you have a tremendously large task ahead of you to create a valid DXF file in a text editor. There is a huge amount of header information required in a DXF file for even the simplest shapes.

If you are serious about it, your best bet will be to start with a blank (no entities drawn) DXF file that has been created in a CAD package and use that as your base. Then you can add entities to it as needed. You will need the DXF file specification. I use the R2000 spec since it has all the needed functionality while still being backwards compatible with the largest number of systems.

If you are doing a conic frustum, you will need to investigate the ELLIPSE entity, and if you are doing a pyramidal frustum, you will need the LINE entity. Depending on the level of complexity you want and the version of the DXF spec that you work from, you can also use the SURFACE entity, but in a DXF file, this will just be represented as a series of lines forming a grid(polyface mesh). You can also use the 3DFACE and 3DSOLID entities, but if you really want solid geometry, you're better off using a 3D file format as mentioned above.