To represent the changes in design, here's a cap cutaway on the exact model of the Lumix GH3 end cap and my newly revised design.

The blue zebra cross section represents a cross section of the OEM Lumix hinge cap.

The red zebra cross section represents a cross section of my thick walled end cap.

The cross sectional thickness of the walls on my end cap are 0.4in thick, where as the measured cross sectional thickness of the OEM lumix end cap is 0.0365in

Three .STL files are attached to this guide.

"lumix cap square R2" represents a square profile end cap with the same wall thickness as the OEM lumix end cap for greatest chance of compatibility across GH3 & GH4 cameras. This is the most tested end cap design. This is the best file to download as it should fit within the accepted assembly tolerances followed by Panasonic.

"lumix cap beefy R3" represents a square profile end cap with thicker walls for greatest durability. This may not fit all GH3 & GH4 cameras due to natural variation in assembly tolerances between batches of cameras.

"lumix cap identical R2" represents an end cap as close to the original OEM end cap as possible.