I put some 1" pine boards in DH kiln yesterday that has been air drying for 6 months now. I check them around 13%. After getting them dry to below 10% do you run the temp up to kill insects on pine also?
Because it's pine, and it's well air dried, I would say just crank up the temp and get the last 5% moisture out of it, and cook any bugs at the same time.
If wood is well air dried it's hard to mess up in a kiln, so crank things up and finish the wood off. Couple of days.
I sterilize it just like hardwood which also serves to set the pith.
ok thanks
just check the pine and it shows in the 9% was thinking about doing what you suggested and turn up the heat but its dripping steady about two drips a second. Maybe my top boards are dryer than others. Would you go ahead with the heat or wait till dripping slows down?
My last load I waited till dripping slow and it showed about 6-7%. I read here once that 10% is good enough for pine.
Less than 10% has been fine for me. When you ramp up the temp and open the doors to refill the wet bulb bottle during the sterilization cycle, you will discharge some water vapor, so if you are at 9% now and heat up to 150 degrees and hold it for 24 hours, you will lose a bit more water and come out perfect.
I also anticipate losing 1% or sometimes a bit more on the sterilization and cool down stage as WDH says.
I just plan for it, like Kentucky Windage.
When you are sterilizing pine, what are you trying to kill? I didn't think PPB went for pine and ambrosia beetles leave when the moisture content is low.
The only dry wood insect for softwoods in North America is the Old House Borer, which only infects new wood. Damage is slight most of the time. There is also the termite, but that comes after construction.
For most softwoods, 9 to 12% MC is the common moisture level. Drier means lots of machining defects. Due to low shrinkage, a little drying in use is ok.
Flatrock, for me, it is more of a pitch set than a sterilization in SYP.
Danny, Thanks, I was wondering. I thought I might have missed something. The pine I cut a couple weeks ago for tables will need to have the pitch set for sure in a few boards. I will have to try that.
Quote from: WDH on August 19, 2017, 07:24:08 AM
Flatrock, for me, it is more of a pitch set than a sterilization in SYP.
Me too, except for those big pine borers, the mice, carpenter bees, and wasps building their nests between the stickers when it's air drying. Also the occasional snake. :o
We are drying some 8" and 10" wide longleaf pine in the solar kiln. It will be used for flooring, and we will transfer it to our hot box to set the pitch and finish drying. We will probably run it at 150-160° F for a day or so. It is at 15-16% MC now. I think 10 or 11% final MC will be appropriate for this "barndominium" floor.
I was thinking of putting it in the hot box at around 12-13%MC. Does that seem right, or should we pull it down a little lower?
That should work. Check it before you take it out of the hot box. If it's still a little high, then leave it in the box a little longer and do some venting.
Robert, I can add another critter to your list. Was moving pallets of lumber in the shed the other day and when I picked up the bottom pallet a opossum was cured up in a pile of leaves. Fella must have liked his spot barely moved when I picked up the pallet of lumber.
Several beetles around here will get in White Pine as soon as it hits the ground, maybe even as it is falling...
Black Turpentine beetle for one. When I saw up pine that has been on the ground for awhile, the outer bits look like wormy chestnut. Wife actually likes the look and so I save all those boards for a project she wants. The floor of the kiln was full after the last batch during sterilizing.