Centre / Rim Marks
Standard Mesh Grids
An Asymmetrical mark in the rim allows for precise orientation of the grid, and aids in the identification of each side.
More recent grids have an asymmetrical centre marking, enabling the four quadrants of the grid to be distinguished.
Older grids have a ‘reverse arrow’ centre marking, enabling each half of the grid to be distinguished.
Note that the central hole is for manufacturing purposes only, and may not appear in the actual grid.
Fine Mesh Grids
An Asymmetrical mark in the rim similar to that found in the standard mesh grids.
Only some of the ‘HH’ series of fine hexagonal mesh grids have this centre marking. It effectively divides the grid into six distinguishable areas.
The older HS and HH grids also have a circular tab on the rim to aid in handling the grid with tweezers.
Note that no grid has all of the above three features together, the diagram is for illustrative purposes.