What should I model next?

I need a break from my modeling of a dragon 3d print model and also having a few beers in me, so…

It’s been a hot minute since I modeled something to share as a cnc grey scale height model pattern.

So until 23 Nov 2023, 2359 CST give me your inputs.

From any inputs I get, I will pick my favorite and model and create a cnc pattern to share as a grey scale height map model and will also carve a draft of the pattern to show what it can look like.

For a future project, I’d like to know how to take a photo and then carve it into a 3D wall plaque on my CNC. Caveat: using free software :grimacing:


If its a lithophane then its pretty simple.

  1. Take the photo and convert it to greyscale. (Krita)
  2. Use the greyscale photo to create a 3d model using displacement. (Blender3d)
  3. Export as STL. (Blender3d)
  4. Use STL file with your CAM of choice to create the gcode.

Sometimes in a very rare occasion you can just convert the photo to grey scale and it will give you a usable pattern. But in my 11 years of 3d modeling that has only happened for me once and it was still somewhat noisy. (Same process as above but there are also free image to stl or lithophanes websites that will do this)

If you want a good 3d (2.5d) representation of the 2d photo then not so easy.

Traditionally, It was done manually by a 3d artist sculpting and modeling. Can be time consuming and requires a high level of skill. (Blender3d, Sculptris, 3dCoatPrint)

I am not good at it but you can paint on the 2d image and create a height map manually. Had an old acquaintance that was really good at it and made excellent patterns that way. I personally have never been good at this technique.

New option is to use AI. Still nascent but pretty cool. Standard Diffusion XL is a free AI image generator and what I use. You will need to use the control lora depth rank (height map generator controls for SDXL). My results are a little crude but a great starting point to then take into a 3d modeling software to clean up and refine. (SDXL, Blender3d)

For any of the options you want a simple image if possible. CAD is not the best option to clean up the 2.5d model and you’ll want to use art focused software like Blender, Sculptris or 3dCoat Print (all free).

It will be a raster carve.

What type of image are you using (just general type)?

R- Oscar

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An old moonshine sign with a fool moon in the background…

Nice Blender work BTW!

Thanks and thanks for the input. Its on the list.

Have you seen this? Photo to Mesh. from Ransen Software and a free demo before you buy. I’ve been using it for a couple of years now and find it excellent value


I’m a linux user DuncanC so that won’t work for me… same for numerous other software, especially since I use Red Hat based linux not even Debian, so there is even less for me… So I have to step up and be inventive…

I use Blender, and either model / sculpt it or cheat and use Gimp to process an image into various BW parts (I did start to automate this recently using OpenCV) and then take the images into Blender where I use the displace modifier and various material techniques, before converting to a mesh, then using subsurface to smooth if needed before sculpting in some finishing touches. Then I render out a normalised height map using the compositor.

Next I use dmap2gcode by Scorchworks:
Whilst writing this I just discovered a new branch I’ve not seen before:

FYI also by Scorchworks I use F-Engrave:

Because my ex was too scared to even sit in-front of little apps like Blender or FreeCAD, she made some height maps by layering up shapes in Inkscape, simple but works, especially when using Hombres (a.k.a. gradients, but it’s what all the cool kids over at Cricut call gradients)

Have fun

Besides @Scorch’s dmap2gcode, @stewart’s free, open source Kiri:Moto runs in the browser and is extremely capable. It can handle both depthmaps and objects. It’s a general CAM/slicer that handles 2.5D routers as well as 3 axis and 4 axis (3+rotary) milling, lasers, resin 3D printers, and FDM 3D printers. It’s a work of art that deserves to be better known!

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Oooh, I likes it I do! Good for wooooOd!

Yeah, I only had ten minutes, so I’ll finish watching later, especially for the laser section and I currently can’t start Cura due to init screen being too large and buttons un-tabable, so it may fill that gap too… Thankyou

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I’ll start modeling after the food coma goes down a little this afternoon. Happy Thanksgiving all.


Duncan, nice find. Blender3d (free) can do the same though it takes a little bit more work. 4 steps vs 1 step.

But back to the discussion, you see how noisy and distorted the 2.5d geometry looks like from the website examples. Great for lithophanes but you would need a grey scale height map image to create what I would consider a true 2.5d representation of a 2d image. Though again you could get lucky and get a good model doing it this way.

This is an example of what I think a true 2.5d model should look like. (I am cheating since I started with a 3d model)

@Oscar it would be a photo [.jpg] of my parents.

Don, I was worried about that. Probably one of the tougher options. What I would do is:

1st attempt: Convert to greyscale and see how good or bad it looks as an STL. Again, sometimes you do get lucky.

2nd attempt: Use SDXL and see what AI can do.

3rd attempt: Sculpt the image if feasible.

Grey scale height map image pattern:

Individual elements if you want to combine for a new scene.