9. Take a middle brace and insert 5 M5x10mm
screws into the holes and finish them off using
M5xT-nuts.
10. Attach it to the vertical AL beams. The inner
edge of both beams should be 170mm apart.
Attach a 460mm 2020 beam to the middle
brace.
11. Repeat steps 9 and 10 on the remaining 7
middle braces. Note that the front and back
are 500mm AL beams and the sides are
460mm 2020 beams.
12. Flip the frame over. Put a M5x10mm screw
through a rubber foot and finish it off with a
M5 T-nut. Attach this to one of the corners on
the bottom.
13. Repeat step 12 for the remaining three
corners.