Subsurf or volume shader for 3d print material

I’m wondering what would be a better shader for 3d print material.
So far i used principled BSDF with subsurface settings.
However i’m a bit in doubt if thats correct shouldnt it be a combination of a volume shader and glossy ( glass??)… instead.

(i’m not after layer effects, since our printers print to fine to see layers)

Its more that thin parts have some milky shine through effect, and thick parts dont have this, and i have doubts subsurface materials is the way to go with this.

what’s your thought on this.

I was thinking about the same thing today, made the shader below, but i’m not convinced by it yet. The problem with 3d printing material are the edges, about 1 mm or so they get a bit like blue-white milkglass shine through effect.

Originally i thought of using a glass shader, with a fresnell though it doenst do anything with egdes, pointiness the same thing.

here’s my shader, notice it goes to the normal material output (not in the picture) (no volumetric input).

Sudden idea update, looks better now

Using ambient oclussion to find the edges on the object, (i reminded the shaders for grunge effects), for testing your type of material replace glass shader with red diffuse bsdf, so you can see how much effect of it you see, which might depend this shader looked nice on STL scales of my object.

maybe one could also invert the ambient occlusion as roughness, so the borders get a bit glossy while the inside is more roughly, but i think it depends on your 3d printer how you finetune above shader. I’m using an objet industrial printer, (13 nanometer or so) so it might be effects other people dont have.

Any reason you’re not using randomwalk on the principled shader node? Randomwalk is MUCH better than Christiansen-Burley at doing the milky/glow look along thin edges you mention in your OP. Remember that when you’re mixing the SSS and Principled shaders, you won’t get any specular reflection on the SSS shader side. So it’s better to just use Principled for everything if you can.

Also, your 2 SSS shaders at the top of the graph look like they’re just varying radius by color? You can change that by clicking on the radius input and just changing the constants, should be somewhat faster/more efficient than sampling 2 closures.

I simply didnt think of randomwalk, i’ll try it.
The problem seams a bit that the ‘glass milk alike edge’ can be transparant but it shouldnt get dark edges (which sometimes are seen too in my renders). the two SSS shaders (with different radius) where to mimic the radius volume (as for volume shaders i couldnt get it to look like it., they seam to absorb to much light and dont get me the edges as in real). But i’m open to other shader reciepe ideas.

Below a detail of a real 3d part photo showing the effects i’m after :