1
$\begingroup$

In Blender I have a curved surface, only quads. Now I want to "engrave" the surface. See picture as example, but only with curved surface of object instead of flat.

engraved surface with dynamic profiles Good example of how it should look printed

how to put a curve like this onto mesh? How to cut this out off the object?

What did not work:

  1. boolean in various combinations. Tried making curves with triangle profile, putting them on a lattice for deforming them to shape and shrinkwrapping the lattice onto my object. Then booleaned curve with object and tried to delete all excessive faces. Lots of ugly triangles.

  2. Making only the outline of my desired engraving and knife projecting it. Then, having the outlines, extruding them into the object and tried scaling them. While this somehow seems to work a little better, I still have very ugly tris for subsurf and complex shapes do not really scale or offset well.

  3. Trying to sculpt with Dyntopo enabled. Maybe there would be a way with a certain sculpt tool, but Dyntopo makes ugly geometry, too...

What do? Do I have to remodel the whole object and manually building all the complex engraving? Thanks for your time in advance.

Edit: I want to 3D-print this, so bumpmaps are not an option here. Also please note that the engraving has to be CUT OUT of the object, not a curve put on. If by any means I could export my object into another freeware program or use another program altogether to more easily get the desired results, please let me know.

$\endgroup$
  • $\begingroup$ If you want to get away with out modeling everythigng. You could always try micro displacement feature. Convert your image into a 16 bit Tiff gray scale image. Then use the image in your displacement output. I don't know how close the camera is going to get to the object. Just an idea. $\endgroup$ – icYou520 May 12 '17 at 17:40
  • 2
    $\begingroup$ My approach would be to do the shapes on a design program like inkscape or illustrator, expott an image to be used with a displacement modifier (or even as a bump map, depending on the desired use for such object) over a flat surface $\endgroup$ – cegaton May 12 '17 at 17:53
  • $\begingroup$ icYou520 and cegaton thank you both very much for the suggestions, didn't know about micro displacement! Unfortunately, as I want to 3D-print (added to question), this is not an option here. $\endgroup$ – gebar May 13 '17 at 10:08
3
$\begingroup$

You could try and model it with Bezier Curve objects combined with a Shrink Wrap modifier. Just model use a any bezier curve object, define any desired section and use it as bevel object.

Apply a Shrink Wrap modifier to the curve, but the important part is to activate the option Apply this and all preceding deformation modifiers on splines’ points rather than on filled curve/surface.

This will make it so the bezier control points are wrapped to the surface, rather than the final beveled geometry, so that the curve can be beveled live, but its thickness and shape is kept.

Then adjust and model as desired, you can use curve radius to make certain parts thicker or thinner.

enter image description here

$\endgroup$
  • $\begingroup$ Hi Duarte Farrajota Ramos, thank you very much for your detailed answer. Didn't know this option existed. But this was not exactly what I needed, maybe I was a little unclear: I need the shapes to be cut out of the object, not laying on it's surface. (Like as if I would use boolean to substract the curve from the object) And in a way that it is 3D-printable, means no holes, and no ugly geometry. $\endgroup$ – gebar May 13 '17 at 10:02
  • $\begingroup$ Ah I see, didn't get that. Maybe you can use this as modeling technique, then in the end, create a copy of all objects, convert your curve into a mesh object. Do some cleanup, remove doubles and close wholes, then use a Boolean modifier. Have in mind that it is likely to fail or produce bad results, and will invariably produce bad topology. $\endgroup$ – Duarte Farrajota Ramos May 13 '17 at 12:25
  • $\begingroup$ I have found by now a solution on my own (see my answer), but thank you so much again for your suggestions! $\endgroup$ – gebar May 13 '17 at 12:33
  • $\begingroup$ Another possibility may be using sculpting on a high res mesh. Not really sure how that would workout, not something I am accustomed to using myself $\endgroup$ – Duarte Farrajota Ramos May 13 '17 at 12:33
0
$\begingroup$

You have to decide if you want a perfect model or if you want something good enough for 3D printing. You say you get lots of ugly triangles with booleans, does it really matter for the 3D printer? My experience is that ugly triangles doesn't matter when you slice an object. As long as it is a manifold object. Use the "carve" method for the boolean modifier.

My first suggestion (good enough for 3D printing): Subdivide your objects until everything is really fine, really really fine. Use booleans or a displacement map. Apply modifiers. Use the Decimate modifier to get back to a more reasonable geometry.

My second suggestion (perfect model): Use any method that you have tried before that results in ugly geometry. Create a new mesh along the old. Use snap, shrinkwrap modifier etc to align it to the old but with perfect quads. This is known as retopologize and you will find lots of sources on the net for how to do this. It will be hard (and in my opinion unneccessary) work but you will get a perfect model this way.

$\endgroup$
  • $\begingroup$ Hi Gunslinger, thank you very much for your comment! I have to say, for 3D-printing it depends on what you are trying to achieve. For very small, detailed models with high resolution printing it is very annoying if those small lines are not well done to begin with - and that is what I need for this project. Of course, the less detailed the printer is, the less it will matter. -- Your first suggestion was a sluggish one on my setup at least, I gave up on that. -- Second suggestion I will definitely try some other time! Thank you for that! By now I have found the solution to this myself. $\endgroup$ – gebar May 13 '17 at 12:19
0
$\begingroup$

Have found a solution for my problem!

I did not resolve this in Blender. I used Sculptris (free) and MeshLab (also free).

  1. Convert model as subsurfed as you need it to .obj-file via Blender.

  2. Open in Sculptris and make engravings.

  3. When finished, export as .obj again.

  4. Open in MeshLab and export as .stl.

There you have it!

enter image description here

Of course, the functionality of Sculptris prevents exact changes to "curve"-shapes, you have to eyeball it and make adjustments as you draw it. But for me, this proved to work very nicely.

Thanks to everyone for your contribution, first time asking a question and I already got such marvelous ideas from you all and learned alot!

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.