Hey Carl and Lynn,
I plan to make the wasteboard slats of HDPE (see HDPE wasteboard example). You know the stuff of which milk bottles are made. It is resistant to all liquids including acids and lubricants. It is not directly cheap, but has many advantages, and it can be recycled by 100% by simply melting it, it cannot be glued but it can be welded. I have a source here for 169,25 € / m² incl. VAT in black 15 mm thickness, so much less expensive than aluminium.