CB Woodworks, Inc. uses a combination of solid poplar
and MDF. All framing members are solid poplar,
while the panels and lids are MDF. Poplar is
an excellent choice as it's a hardwood and
tight-grained, which makes my covers very strong and
allows for a smooth coat of paint. I use MDF
for my panels and lids as it's a man-made product
which is very stable. This means it will not
expand and contract with humidity changes like solid
wood does. It remains flat and resists
warping. It also takes a smooth coat of paint.
Moisture resistant wood glue and pocket hole
joinery make for a strong radiator cover.