Air drying birch - how long?

[jonathan snyder]

Hi folks,

I have an opportunity to buy some nicely spalted paper birch at a buck a bf (kiln dried birch runs almost 3 bucks a bf). The trees were cut last fall and milled last may. It has been stickered and covered outdoors since. No idea what the MC is and I dont have a meter.

Anyone have any experiance with air drying paper birch? Seems like I read somewhere that a good rule of thumb is 1 year per inch for air drying. I that about right? Would it continue to dry, if stickered, covered and stored outside through the winter. Seems like it might not dry at all if left outside during winter. I was considering storing it in my travel trailer for the winter, but that might not be a good idea. What do you folks think?

I dont have a lot of room to store it indoors, but if the spalting is as nice as the fellow says, it might be worth picking up some and making some room. I could store a small amount in my garage, but it is only heated while I am working in there. Would that seriously retard the drying?

I know I just asked lots of questions, but I have never bought wet wood before.

Thanks
Jonathan

[Gary Breckenridge]

:cool: Yes, the year per inch is true. And then when you bring the wood into a heated living room it will go through another shrinking phase. Somehow I don't like the idea of the on and off heat in your shop. I've found that if I outdoor dry wood for a year per inch and then leave it in my heated basement over two winter months its ready to go. Rocklers has a moisture gauge for $123.:cool:

[Ian Abraham]

Seems like I read somewhere that a good rule of thumb is 1 year per inch for air drying. I that about right? Would it continue to dry, if stickered, covered and stored outside through the winter.

The one inch per year is a very conservative rule of thumb, if you leave it that long, any wood in any climate will be basically air dry. It may be much faster, depends on species and climate. Yes the wood will continue to dry outside in winter, but I notice you are in Alaska, so it may not dry very fast :D

I think you need to work out how dry it actually is. If you dont have a meter you can do this by microwaving a sample and weighing it as it dries out. Use low power in the microwave and dont let it get too hot (it could catch fire :eek: ) Weigh it every few minutes, when it stops getting lighter it's "Oven" dry - 0% Moisture. Now you can do some maths and figure out what the sample's mositure was when you started.

If it's air dried to ~15% then you wont harm it by bringing it inside - stacking it in a trailer, whatever. It's still going to be slow drying if it's in a cold place, but it wont harm the wood. If it's over 20% you are best to leave it outside where more air can circulate. I imagine winter drying will be slow, but it will continue to move toward it's equilibrium moisture.

If you want to work with some soon, stash it in the house, under the couch, spare room, attic or whatever. You should be able to hide a small amount ;) . Air dried wood stored for a couple of months in a nice warm house will be fine to work with.

Cheers

Ian

[Jim Becker]

1" per year is a general value and varies by species. A moisture meter is really what you want to use to know when the process has reached the goal. Some wood will be ready sooner and some will take much, much longer. How you construct your pile, where it is relative to air movement, etc., all will affect your time result.

[Scott Banbury]

I would think that its MC is as low as it will get outside by now. I'd bring it into the shop now to further acclimate--leave it on sticks for a month or so in the shop and it will probably be alright to use.

Do get yourself a pinless meter though ($150 buys a good one). It's really essential to make sure that all your joints are made with pieces that are the same MC.

[Chip Charnley]

I milled over 2400bf of mixed hardwoods (RO, cherry, maple, walnut, hickory, basswood) in FEB 2005. By August 2005, it was all pretty much under 20%MC and much of it was in the 12%-14% range. By Xmas it was all 10%-14%. It all depends on your location; RH, wind availability, how much you shroud the sides (I didn't do any despite the oak content as it would have probably damaged the maple and cherry), etc.

This is all leading up to say that the first thing you should do is buy a moisture meter or find one to borrow. I had never milled lumber before (and would not have in 05 if not for having all the trees free from clearing for my new house) but I would have been lost without the moisture meter. I am with others here that there is a high probability that that birch is in the 10%-20%MC range now. If you are going to have it kiln dried before final usage, you might just as well do it now as later. If you want to just use air dry lumber, re-sticker it with a good roof in a place with as much average air flow as you can get and move it inside in a few more months for final acclimation.

As to whether or not you will get much drying in the winter, it really depends on your location. If it gets cold enough, consistently enough to freeze the logs and keep them frozen, you won't get much drying. However, if you are in an area like me where the RH isn't bad, the prevailing winds are not dead, and the temp does a yo-yo imitation around the freezing mark, then yes, you will get a reasonable amount of drying. If you have the same conditions but the temp never foes below 40, you will get a fair amount of drying. So, again, it depends on your location.

[jonathan snyder]

Hi folks,

Thanks for the advise. I live in Alaska and fall is coming on pretty fast, with winter right around the corner. What i'm hearing is that if left outside or in the shop which is only heated part time it will probably not dry much.

I'm going to go take a look at it tomorrow evening. If it is nice stuff, I will probably buy a few bf. I will find a place to sticker and stash somewhere, maybe under the bed!

Thanks again
Jonathan

[Don Baer]

Jonathen,
Ya might try two aproaches. Get some to put inside under the bed or what ever where you know the humidity and put some other out of the weather in the garage where it may not have the benefit of soem sort of heating but I'll bet as long as it is out of the weather it will continue to dry. Although you have severe winters and it snows what is the humudity. I'll bet it is as low as we have here in AZ. It's a dry cold...lol. :D Give it a try, I think you'll be suprised.