Blender>Unity cracks between connected models

In Blender I made a jigsaw puzzle made of custom shapes extruded from an svg. When I import the fbx puzzle pieces into Unity they are all aligned, but I noticed there were a bunch of tiny pixel size gaps in between the puzzle pieces right on the edges of them where the connect with each other, it is especially noticeable when panning the camera around the scene, you see all the tiny gaps appearing and disappearing. In both the SVG and Blender file everything is perfectly connected and aligned, pixel perfect with no gaps, it's just once in Unity all these tiny gaps start appearing. Not sure if it is something with the model import settings, maybe a project setting I can change in graphics/quality. I've included some screen shots showing the mode in Blender which is seamless, and in Unity with a diff texture so you can see the gaps/seams. Any help would be appreciated, thanks.

 

Not sure if it's entirely related or helpful, but I notice the same exact problem when making pixel art tiles. Seams are perfect everywhere else, but not in unity.

Usually a couple methods fix this for me:

1. Change the texture importer setting from clamp to repeat.
2. Enabling anti-aliasing.
3. Slightly scale all the UVs down by small amount.
4. If #3 isn't possible, slightly scale up all transforms in unity by a really, really, small amount (messy, but works).

If you're using complex meshes though it's more likely a vertices floating point mismatch. Does the same thing happen if you try exporting is as an OBJ file, or use the .blend version in unity?

 

Ok so I figured this out, the problem has to do with Blender. I was making my models by converting SVG to meshes in Blender, even though Blender does not show any seams they show up in Unity cause the overlapping curves cause the verts to be slightly off. So I instead used a plane and knife project the svg curves onto the plane to make the pieces, I also had to lower the stroke size on the svg to 0.2-0.1 to get the tightest cuts with the knife on the meshes.