The Forestry Forum

General Forestry => Drying and Processing => Topic started by: xlogger on October 16, 2019, 05:23:03 AM

Title: maple under fans
Post by: xlogger on October 16, 2019, 05:23:03 AM
I cut up some 9/4 live edge maple slabs about 5 weeks ago and kept them under fans. I check them yesterday in 4 different spots and got from 22 to around 27 mc. Is this a normal drop? I'd like to put them in kiln but will wait a little longer. Rather see most of the reading nearer 20.
Title: Re: maple under fans
Post by: WDH on October 16, 2019, 06:56:44 AM
I put some green 9/4 under fans on July 10.  90 days ago.  We have had the best air drying conditions in years (except for oak but good for most other stuff) with the very high heat but lower than normal humidity.  I checked them this weekend and they are between 12% and 16%.  So, I am not surprised at what you are seeing.  

I talked to Jake yesterday and he is seeing the same thing. 
Title: Re: maple under fans
Post by: YellowHammer on October 16, 2019, 07:18:32 AM
This has been a great year for air drying.  I have been seeing the same thing.
Title: Re: maple under fans
Post by: customsawyer on October 16, 2019, 07:35:53 AM
I would bet any damage done in the drying process has already been done. Maybe leave them out a little longer until everything is below 25% and then stick it in the kiln.
Title: Re: maple under fans
Post by: GeneWengert-WoodDoc on October 16, 2019, 07:48:25 AM
Oftentimes, because of the damage done to well air-dried wood that gets rained on, it is best from a quality standpoint to put lumber into the at around 30% MC.  When air drying under an open shed, lower MCs are safe.  Note that when starting a kiln with air-dried lumber, use an EMC in the kiln that is 1 or 2% drier than the average outside EMC (which is typically 12% MC).  Never go wetter.  Start up maybe at 115 F but go rather quickly to 130 F if that is the temperature in the schedule.

So, if you have an empty kiln now, go into it promptly, especially because it finally looks like we will be having rain.

Note that except for starting too humid or over drying, you cannot damage air dried lumber under 30% MC in the kiln.
Title: Re: maple under fans
Post by: xlogger on October 16, 2019, 06:08:40 PM
The stack I'm asking about is under the shed, no rain and I do have a load of Ash finishing up now. Danny, has you load been under fans that long?
Also now that is cooling down do you still use the fans as much?
Title: Re: maple under fans
Post by: WDH on October 16, 2019, 09:26:08 PM
I ran the fans for all except the last 10 days when I had to be gone for over a week.  With maple, I always start with fans. 
Title: Re: maple under fans
Post by: Southside on October 16, 2019, 10:20:57 PM
How did the color hold?  I sawed some this evening and it is snow white, I was actually surprised as most of the maple I have seen is much more dull or has ambrosia in it.  I felled this one in a very wet spring hole I opened up for a pond a couple of weeks back.  Maybe a foot of top soil if that then white marle, sopping wet under the surface with a ph of 8+.  Was wondering if the lime in the soil would affect the lumber the same manner minerals will darken poplar.