From waste material I made this gadget ,that takes part in the measurements and when assembling the cabinet:
And I am approaching to the measurement of the internal volume:
I fill the cabinet with water to the red line / there ends the front panel with the speakers /;
-The amount of water is 42 l. in the box; 42-3,5/the mass of the ribbing/= 38,5l, 4.5 l more than what's needed - what's next?
I know the total volume, now everything is very simple there are several options for correction;
- purely mathematical / small planarity, simple algebra and axonometry /
- methodically- it can be done in several ways.
There are several possibilities to reduce volume of the cabinet , but for them later.
joro