Any tips? I have to get a load equalized and conditioned.
I'd think that would depend on just where you are at with the load, as far as mc variation (within boards and between boards) and drying stresses in the lumber. Have you been sampling along in the drying schedule?
my sample is at 13% I haven't tested for tension
Dan,
What species
what thickness
did it go in green or partially dry?
How long has it been in the kiln?
What is the delta between the shell MC% and the core %?
What are your current kiln settings (temp and RH%?).
Typically to condition you can add some water into the kiln (but don't wet the lumber) by spashing several buckets of water on the floor (compressor off) or injecting steam. It's best if you have an idea of the core and shell MC%'s in advance though.
Thanks Scott,
it is white oak
1 1/8" thick
been in the kiln 35 days
How do I determine the delta between the core and shell?
kiln set at 120 degrees and 40% relative humidity
Dan, to get that delta MC, cut a wafer about 1" wide. Bandsaw 1/4" shell off the wafer. Weigh and bake the samples. Easy if you have the set-up. Weighing is difficult if you don't have a digital scale or an old triple beam balance. I use an old toaster oven but you can use a microwave if you're careful.
Dan, in addition to Den's method you can use a moisture meter with insulated pins that are 1/2" long. Take a reading after you've penetrated about 1/8" into the face of the board (shell), and then another reading when the pin's are fully inserted into the board (core).
At 35 days, unless it is QS you should be in the ballpark. Depending upon how rapidly you dried it from green, it may be within one to two percentage points between shell and core.
Generally I condition by sterilizing the load at 135 (assuming that I'm within 1% or so delta between core and shell), and then adding 30 - 40 gallons of water into the floor of the kiln, turning the compressor off and letting the temp drop down over a 2 day period, leaving the fans running. As the kiln cools down, the RH% goes up and the lumber equalizes.