All parts maked grey on the 3D image of the cabinet are 'sandwiches' made of 3 layers of 12 mm HDF, the middle filled with sand. The easiest way to do this is to use three equally sized boards, and make a large cut-out in the middle board. I made a square cut-out leaving a 70 mm wide rim. The open space inside should be supported by spacers to avoid warping (see photo). All other boards are 19 mm HDF.
The vertical braces inside the enclosure are one piece, the horizontals are three separate pieces. The spacers inside the port runs all the way back to the rear wall (this is hidden on the 3D image), and so do the braces. The front baffle consists of two layers of 19 mm HDF.
Parts list, one cabinet
Part name size in mm # of layers material Side wall 800 x 700 3 12 mm HDF Top / bottom 800 x 530 3 12 mm HDF Port 674 x 530 3 12 mm HDF Rear Wall 628 x 530 3 12 mm HDF Front baffle 512 x 530 2 19 mm HDF Port spacer 739 x 80 1 19 mm HDF Vertical brace 512 x 726 1 19 mm HDF Middle part of
652 x 170 1 19 mm HDF Outer parts of
726 x 161 1 19 mm HDF
Details, vertical brace:
Details, horizontal brace:
The cut-outs are 390 mm for the inner baffle and 355 mm for the outer baffle.Stig Erik Tangen