Summary

Tile spacers for standard 1/16" (1.58mm or 1.6mm) gaps.

There are files for center pieces, corners, and edges.

They are actually modeled to 1.35mm gap, but due to corner bulging, it resulted in a nice 1.6mm gap on my printer. You may need to scale up or down a little to match your specific printer. Print one as a test piece and measure with calipers to see where you're at.