Do people do precision modeling in Blender and if so how?

Mainly do they make sure that the values are even with no decimal numbers behind it such as 74 instead of 74.347 or something like that. I’ve found that whenever I extrude in Blender, even when the vertices are on the same plane (like x or y or z) that there could be some numbers behind it sometimes even with grid snaps. It’s nuts to me. I guess that’s why I want to know. I’m going to have to move on from thinking about this soon, so I’m getting my last questions about this out of my system.

From what I’ve been told Blender’s not a CAD program and isn’t intended for precision work. That having been said, the TinyCAD add-on (already in Blender) may be useful to you. And you can go into a vertex’s XYZ in the N-panel > Item to type in the precise location you want.

try it in 2.8 it has more options for units

and don’t forget that Bl is still limited to single precision and not double precision with 15 digits
but for most things should be ok

happy bl

Would also add that Blender uses single precision floating points, which is where you get those numerical errors.

There are also later replies in that thread mentioning 3D printing. Yes, people use Blender for 3D printing, very much possible. But tolerances in 3D printing is like throwing a rock at a barn door and missing not only the barn, but the whole country.

More precision in polygonal modeling means more edges and vertices, which also means less control you have over the model. If you need that, you also need to figure out new workflows to deal with that, with the existing toolset. It is the reason Subdivision Surfaces was developed, which defines curves and surfaces with more geometry, with just fraction of control geometry. But that doesn’t help with precision because polygonal modeling is inherently inaccurate, and subdivision surface algorithms are approximating ones instead of interpolating. The result is an approximating mesh approximated again.

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This was very informative to me. I heard people talk about floating point, but I appreciate you linking that Youtube video in the response because it explained a lot. Now I know some of it really isn’t me and some of it could just be slight rounding errors because of the way this is interpreted in Blender. This changes a lot of what I thought. Now I know that getting absolute perfection in Blender all the time would be like pulling teeth because of approximations instead of it being absolute.
I wish there was a way to change it to something more precise. Doesn’t that mean that no models made in Blender will be completely perfect, or does it just mean a person would have to work harder to get those results?