Kiln Drying Forum
Wood Drying Topics => Drying Defects => Topic started by: Craig Jensen on June 04, 2012, 01:36:22 PM
-
We are getting more surface check than usual right now on our DF and Larch. The logs are 9 - 12 months old. While the checks are not there on the green product, my kiln handbook says that surface checks happen early in the schedule when the relative humidity is too low. I am attributing these checks to old logs because the drying times have reduced from normal by about 25%, indicating a dryer log going in, and lower wet bulb temperature than normal during the first part of the schedule.
Does this make sense to anyone? Any ideas? Has anyone heard of using steam spray early in the schedule to avoid this?
Craig J.
-
try activating your spray early I activate mine within the first hour lower your depression and reduce fan reversal I use every hour for old logs just tested this on some old DF logs that were decked last Oct and increased recovery by 2-3% not a drastic inprovement but every little bit helps in this economy
-
Thanks Kevin,
I'll try that. Our fan reversals are every half hour for first 2, then every hour after, but had not tried steam spray yet.
Have you tried it on Larch?
CJ
-
No Craig, we don't cut much Larch anymore here. In the last year we've only ran 1 day of Larch. We ship most of it to Chilco or you.
-
"try activating your spray early I activate mine within the first hour lower your depression and reduce fan reversal I use every hour"
This sounded like good advice. If you are now using half hour reversals like I think I saw in a later post, I would go to an hour because the vents open when you reverse the fans and this will increase the need for spray.
Also, make sure the depression is held on the way up in temperature. You might need to ramp up a little more slowly or get halfway to temperature and hold the temperature setting steady for an hour or two to let the wood warm up.
-
Thanks guys.
Will try this. Will let you know how it turns out.
Craig J.