Length 1 groove is staring from left bottom to right top it is not correct
Length 2 groove is staring from right top to left bottom it is not correct
Groove length and width start from center
Because
On top cabinet I don't need groove from end to end I need some gap from end to end
Example if the length is 500mm
I need groove 480 mm at centre as 240 for left & 240 for right and the left bottom I need 10mm gap and right top I need 10mm gap for top panel
In some causes I need from bottom panel also