Mccobb Planner Group desk  

The top is solid.
As are the sides that hold the drawers.
As for the drawer fronts... I'm not so sure.

EVERYONE who likes mid-century should have
something by Paul McCobb in their house! His Planner Group stuff was moderately priced and nice and his Calvin and Directional more refined collections are beautiful too.
I have a pair of Planner Group bedside tables and a dinette set with 4 chairs.

I would guess
That it's all solid (or planked) wood.

I believe there is also a...
I believe there is also a table within the planner-series.
Does anybody have pics of the underside, how the legs are connected to the top?

I have a McCobb desk and agree with barrympls...
Paul McCobb was much more than a modernist. He was not trapped in modernist formalism at all IMHO.
He was a functionalist working in the modern period. His work has more in common with Van de Velde and Koen's efforts to make every line fuse function and beauty during the pursuit of function than with most modernists subjugation of function to geometric formalism.
This is why he is so appealing today.
He shows us again and again that what is important about a rectangle is not its abstract geometric form, but its practical function. He's not even a slave to the golden mean of rectangles, though I have never actually taken a tape measure to my desk.
Increasingly, as I look at the modernist past through a more functionalist lense, I see designers like McCobb jump out of the back ground of modernism and into the foreground of functionalist work persisting through the modernist period.
Form does not follow function in McCobb's products. McCobb's products are not studies in form at all.
They are studies in function. One may not like his acetic, puritanical estimates of what one needs in a desk to function well (i.e., one may prefer bigger desktop area, deeper drawers, more drawers and softer interfaces), but it is his sense of function and not a fetishistic interest in geometric form that drives his selection of areas and proportioning IMHO.

solid
Very well made and sturdy. I have a few pieces i pulled out of my parents
attic. Coffee table, the big square couch side table and the dining table with
the spare extension. My childhood kitchen table.
It is small and i can't believe six of us ate at it as kids. I use
it in my studio as a desk.
The legs screw in but all wood, no metal parts.
My mother claims that she furnished our house on a teachers salary while
my father was still in grad school. All McCobb. Even the couch. All our
bedrooms. The entertainment center. Some of it was re-hashed and painted.
One cabinet is in their shed for potting plants. Another in their closet for
shoes. You could dance on it. 50 years later.

Being solid birch, the Planner Group
pieces can break. I have a lacquered black color square kitchen table with a pair of lacquered black color 'arm' chairs, and the table's showing the lines where the wood pieces are glued together and one of the 'arm' split right down the middle of the seat. I reglued it, but I don't know if it's safe to continue to use.
McCobb's Planner Group was beautifully designed, very popularly priced furniture, but I don't think the construction is as well made as the Eames wood pieces, for example.