Dry enough?

[D6c]

i've got a stack of burr oak slabs in the solar kiln that are about 2 1/2" thick

Checked today:
5.5% on the surface.
8.2% @ 1/4 thickness and 
9.6% @ center of slab

How much more drying do I need?

[K-Guy]

It looks to me that they would average 7-8% with what you posted.

[Stephen1]

I want my center to be 8's , 7's are better. But that is me. Before I had my own kiln I paid to have wood dried in an RF kiln. It was marked with 6 on the ends and 8-9-10's where they  they had probed it. That wood ended up moving in the counter top that I sold it for. They are my friends and so I see it when I visit. I remember that all the timewhen I'm deciding if the the wood is dry enough for the customer. 

[GeneWengert-WoodDoc]

During the wintertime in Ontario, the interior environment is likely 30% RH or maybe a bit drier.  That means the wood will be drying to 6% MC.  In the summer, we likely will see 9% MC as the interior is around 50% RH average.  As usually drying a bit more is much more of an issue than gaining a bit of moisture, we need to target about 6.8% MC coming out of the kiln.  That means also that the shell and core should be at that level.