On Sat, 14 Mar 2015 18:12:59 -0400, Dick Snyder
wrote:

On 3/14/2015 5:57 PM, Swingman wrote:
On 3/14/2015 2:18 PM, Dick Snyder wrote:
I did not finish both sides but even before I finished it,

Always finish both sides of plywood panels.

While the fact that you didn't may not be the entire reason the 1/4" ply
warped so badly, it is most certainly a contributing factor not in you
favor.

What grade was the ply?

Lower grades of 1/4" plywood are notorious for turning into potato
chips, particularly if they are subjected to sunlight and wet conditions
on only one side (even on the ride home to the shop, but a plywood grade
like A-1 usually gives you a better chance.

There are some ways to solve the problem if you have enough clearance.

Might want to consider salvaging your investment by making 3/4" frame
and panel doors, with the top and bottom door rails having a 1/4" tongue
that fits in the groove.

You should be able to cut a tongue quickly and easily with a table saw,
and since it it won't be seen, it doesn't have to be pretty.

You could even make frame and panel doors 1/2" shorter in height, then
glue nail a 1/4" strip on the rails in the appropriate location as a
tongue.

Be creative ...

There are two doors, each 30" high and 37" wide. They need to be able to
pass by each other so that half of the shelves are open at a time. The
shelves will store cook books etc. I don't see yet how frame and panel
doors would be able to pass by each other in the space (depth) that I
have. My current thinking is to find some other 1/4" thick material that
is stiff and would allow me to keep my basic design.
Tempered glass would be my suggestion for 30X37" doors that cannot be
over 1/4" thick - or 6061T6 aluminum.