How to do Modular pieces with ground physics?

So I am trying to make a car drive around, but I want to build maps with modular pieces, so far flat planes + simple flat collision geo

problem I have is the edges that are so infinitely small seem to sometimes cause the physics to hit them, anyone have a good workflow // workaround for this?

I’m not sure to have understood your question.
For instance, you can use a custom collision mesh for your static meshes. As a result, you will be able to have a “physics” geometry which is independent from your actual geometry of the static mesh that is rendered on screen. The downside is that you need to create these collision meshes for each one of your static meshes. Another way is to use “simplified collision”: Unreal tries to generate a simplified version of the static mesh as a collision mesh. Hope this helps.

In any case, if you post more details, I’m sure people here on the forum will be able to help more.

I created the collision geometry, having issues where the seams line up, collision sometimes freaks out, like it somehow hits the infinitely small floating point values between where 2 planes line up