Air Drying Thin Sawn Wood
Saw thin first, then air dry for fastest results. October 29, 2012
Question
I am looking to try air drying some 3/16" thick bandsawn slices of both cherry and butternut approximately 12" wide x 3-4' long. After drying, I plan on thickness sanding into a thick veneer for glue-up onto some cabinet end panels. I know I normally would air dry 1" thick boards about 1 1/2 years, but what seems about right for this thickness? Has anyone achieved success doing this?
Forum Responses
(Sawing and Drying Forum)
From Gene Wengert, forum technical advisor:
Air dry 1" for about 60 warm days. I would not even air this thin material. Just go straight to a kiln or other final drying.
From the original questioner:
I know I'll probably hear some dissent here but I don't normally kiln dry my wood. I've been building cabinets for over 35 years now and a good part of that time used wood milled and dried here on my property. One inch cherry I air dry outside under cover for about one year, then bring in the shop for about another six months or as long as it sits before I need it (sometimes a couple more years). I've never had any real problems and check MC before starting a project. It seems this thin wood could be air dried without a problem. How would it have been done 150-200 years ago?
From Gene Wengert, forum technical advisor:
You are final drying the wood in your shop which is ok, although there is a slight risk of powder post beetles. Unless you have a lot of these pieces, just bring them in right away to your shop. They will dry in about 1/8 of the 1" drying time. Centuries ago, there was not central heating so final MC’s could be higher. As homes got tighter and warmer, the lumber would be in the rafters of a shop where it dried to 7-8% MC.
In your case, checking the MC is critical and is how you have avoided any problems. In fact, people with kilns sometimes (often a lot of the time) do not double check final MC before use and get into big trouble. So, for you I say: Good job!
From contributor X:
Why would you want to dry 4/4 boards you plan to resaw into thins? Saw them now, then sticker and weight them down. I've been cutting thins and air drying them since I first started sawing. The only three species I do this with is mesquite, eastern red cedar, and flame boxelder. Although mesquite sapwood is borer prone I remove any of it for air drying that species of any thickness, so I'm drying only the heart. I kiln dry and heat treat any natural edge slabs or lumber that still has sapwood after edging.
Flame boxelder is 100% guaranteed to have larvae in the wood based on my experience with it. If it has red in the tree it's been attacked by borers, but the bugs and larvae are too fat to hide inside a thin. They get sawn into which is a very common sight when sawing this species. Of course once the moisture drops below a certain percent they would look for a new host anyway if they somehow escaped the blade.
Mesquite thins dry real easy. I sticker them 10" apart as I do eastern red cedar. Eastern red cedar thins reach EMC in a few days. Flame boxelder thins are not as cooperative but not too bad. I sticker them at 6" because they like to get wavy if you sticker them further apart than that. As far as I know none of my thins have given anyone any trouble. I have several projects made from thins here at the house that are as old as six years.
From the original questioner:
To contributor X: I don't plan on drying the 4/4 first, I was just saying how long I dry when I do cut 4/4. I plan on sawing the thin cuts green, then drying, which sounds like what you're doing with good results. Your drying conditions might be a little better than ours here in upstate NY though.
From contributor X:
I see. I agree with Gene about getting them in a better drying location if possible. I don't have a single species down here that takes a year to reach EMC in 4/4. As you noted, my locale and yours are somewhat different.