When 3D modeling, one of the most common challenges is modifying a part without affecting key details, such as the location or shape of holes, slots, or precise details on the mesh. In this article, we will explore how to extend a part in Blender, in this case by 20mm, without losing the difference in the holes or affecting the mesh's curve. The relationship with curves and how to use them to achieve the desired result will also be discussed.
The Problem
A forum user posed the following query:
I have a mesh that I want to make 20mm taller, but I can't scale it by dimension because I would lose the difference in the holes. The main problem is the large curve of the mesh. I've tried adding another similar piece on top, but it gets too tall, so modifying the piece is the only option.
The problem is based on a part that requires a height adjustment without altering crucial details, such as the holes. The main difficulty lies in the curved shapes and how they affect the mesh geometry when attempting modifications.
Available Options
The ideal solution in these types of situations is to work with the mesh geometry without destroying its original structure. To do this, we may want to modify the mesh without deforming the curves or losing the precision of the holes.
Scaling the Mesh Without Losing Details
A simple way to increase the height of a mesh is to use the scaling tool. However, this can create a problem if the mesh has details like holes, as the holes will also be scaled, losing the size difference we want to maintain.
Modifying the Mesh Using Bézier Curves
The user mentions the possibility of using Bézier curves to modify the mesh. This is interesting because Bézier curves allow for precise control over a mesh's shape without losing important details, like holes, and without altering the overall topology.
Solution with Bézier
Instead of modifying each vertex manually, which can be tedious and complicated, we can use Bézier curve tools to create new geometry over the existing mesh. The following describes how to do it:
Steps for Using Bézier in Blender
- Convert the Mesh to a Curve: First, select the mesh you want to modify. Then, go to the "Object" menu and select "Convert to" > "Curve from Mesh/Text" to convert the mesh into a curve.
- Edit the Bézier Curve: With the mesh converted to a curve, enter curve edit mode (by pressing "Tab"). You can now use the Bézier tools to adjust the curve to the shape you want. You can add new control points and move them to modify the mesh's height without affecting the holes.
- Adjust the Control Points: Modify the curve's control points to extend the part precisely. If you have problems with the holes, you can use the "Extrude" (E) function to stretch the curve in the desired direction without altering the geometry of the holes.
- Convert the Curve Back to a Mesh: Once you have adjusted the curve to the desired height, you can convert it back into a mesh to apply further operations. To do this, select the curve and use the command "Convert to" > "Mesh from Curve".
Conclusion
Modifying a part in Blender without losing hole details and maintaining mesh precision can be a challenge, especially when the mesh has complex shapes and curves. However, using Bézier curve tools offers a flexible and precise solution for modifying geometry without losing important details.
While modifying each vertex manually is an option, using Bézier curves is much more efficient and allows for much finer control over the final shape of the part. So, the next time you need to make modifications to a mesh, don't hesitate to explore the possibilities that Bézier curves offer in Blender.
On the forum, you can access the correct answers provided by user Soliman.