WF Substrate Paper Weight vs. Film Thickness

[Stephen Marsh]

Coming from a prepress background, I am used to thinking in paper weight - which is GSM for Australia. In the wide format realm and display graphics, the media (backlit film, vinyl etc) is specified in thickness of MIL or 1/1000 of an inch.

Does anybody have a relative conversion chart/table or formula/spreadsheet for approx. conversions from MIL thickness into weight? I understand that this would be specific to certain media and the same thickness would vary differently for say vinyl vs. backlit film at a given sheet size. Ideally the weight would be GSM, however if this is only available to say US weight I can find conversion charts for US to GSM weight.

I have searched for this sort of info and have not had much luck, which is why I am asking here. Thanks in advance.

Stephen Marsh