topic Re: 3D dynamic block in Dynamic Blocks Forum

3D dynamic block

tsakani_mdabula — Mon, 17 Nov 2025 09:31:13 GMT

I have a tunnel arched profile and it's chevron. I tried creating a dynamic block to be able to change the height, width and length without losing its shape. However, the block I created scale it evenly and not in one direction of x, y or z. I've also tried with a lisp but it loses the shape.

What I want is a dynamic block that I can change a single side like the width or height or length and still keep the shape

Re: 3D dynamic block

Moshe-A — Mon, 17 Nov 2025 10:26:04 GMT

@tsakani_mdabula hi,

First i do not see any dynamic objects in your block.

Second why a flattened 'walls' of the tunnel are build from some small pieces of 3dfaces?

it would be more easy if the objects composing the tunnel would be as simple as possible.

Moshe

Re: 3D dynamic block

tsakani_mdabula — Mon, 17 Nov 2025 10:37:52 GMT

Hi Moshe, the existing tunnels are made of 3d faces as in the dwg. Thus I want to know if there's a way that it can be converted into a dynamic block. At the moment, I can change the dimensions but it takes long as I have to manipulate scale in each xyz direction.

Re: 3D dynamic block

j.palmeL29YX — Mon, 17 Nov 2025 12:51:48 GMT

@tsakani_mdabula wrote:

What I want is a dynamic block that I can change a single side like the width or height or length and still keep the shape

Dynamic blocks are for use in 2D only. What you want to do is not possible in AutoCAD. You' d need an other software, e.g. Inventor or Fusion or similar.

Re: 3D dynamic block

tsakani_mdabula — Mon, 17 Nov 2025 12:51:12 GMT

Thanks Jurgen. At the moment, I convert these faces into a block not tick the scale uniformly. For example, I can check the scales for xyz but it takes some time to get it right. Anyway, I'll check other software to simply it.

Re: 3D dynamic block

j.palmeL29YX — Mon, 17 Nov 2025 15:53:09 GMT

Attached a quick sample how you can manipulate the model in Fusion.

(view in My Videos)

In AutoCAD it is not possible to reach such a level of flexibility.

Re: 3D dynamic block

j.palmeL29YX — Mon, 17 Nov 2025 16:13:05 GMT

@mustafamahdi420302 wrote:

You might want to look into using parametric constraints ... while adjusting width, height, or length.

FYI:

Parametric constraints can also only be used in 2D.