On 03/18/2015 2:46 PM, Dick Snyder wrote:
....

I am going to try to make 2" wide frames out of some scrap pine to see
if they will hold the panels flat. I think I will join them with half
lap joints for now. If that works, I might try miters with splines. TBD

And, if that is reasonably successful, the cherry or other hardwood will
be stiffer. As noted, also, if you go to 2 (or 4 or 6) instead of just
1 panel you add stiffness and reduce the amount of force needed at the
same time (at the cost of more fabrication effort, of course, ain't no
free lunch )

I don't know the ply core. I don't have an instrument for RH but we have
oil heat and it has been a VERY cold winteand spring so far (27 for a
high today) so we had more (dry) heat than usual. The boards were stored
in a vertical position, longest edge down. I will just do my experiment
and see what happens.

Try laying flat covered on clean, dry non-staining material and place a
plastic over it with a water dish under to let it pick up some. Sticker
it so it's got circulation space both sides and add some weight to the
top...see if it will acclimatize back to a more nearly uniform flatter
position then after that when it is brought back to a dry environment.

Have smaller panels just oversize what you need makes this easier to
handle from space considerations obviously...

On edge is really not a good way to store ply altho often given room
limitations it's the only practical solution.

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