iDRY Vacuum Kilns

Sponsors:

Drying oak in saw dust?

Started by Swede, July 07, 2007, 01:02:07 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Swede

I´ve been sawing for the same customer half time the last 3 months. Most spruce but even some oak (with just a few nails  ;D ) . He did as I told him; painted the ends of the oak logs with "wet room paint" and it looks very good.
Now the customer had been told from an old man to dry these oak lumber under a pile of sawdust during a long time. Is this a good advice, for how long and is sawdust from spruce OK?

Swede.
Had a mobile band sawmill, All hydraulics  for logs 30\"x19´, remote control. (sold it 2009-04-13)
Monkey Blades.Sold them too)
Jonsered 535/15\". Just cut firewood now.

jim king

Swede:

As no one is responding I will answer with what little info I have that may or may not be of help.  I dry log slices buried in semi dry sawdust and have quite good luck.  It takes about a year for a 3 inch slice but it has been quite successful so I see no reason that a simple board that is a lot more stable would not work well.

Dodgy Loner

I know there are many turners who dry bowl blanks and slabs in sawdust.  The reason for this is to slow down the rate of drying and prevent the outside of the slabs from becoming drier than the inner portions, which would result in cracks and checking.  This is helpful when drying wood that is either thick (maybe 3" or more) or cut into short lengths, or both - basically, whenever you have a high proportion of exposed end grain to long grain.  However, with most lumber (thin boards and long lengths), there is very little exposed end grain, so covering the boards with sawdust would be counterproductive, as there is little risk of cracking (especially since he painted the ends) and drying time would be significantly increased.  You also run a higher risk of fungus infestation that can discolor the wood.  The only benefit I can imagine is that this might reduce and warping, but if the boards are properly stacked and stickered, that shouldn't be a major problem. 

If your customer insists on covering his lumber with sawdust, then dry spruce sawdust should be fine.
"There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." -John Ruskin

Any idiot can write a woodworking blog. Here's mine.

beenthere

Swede
I missed your post, but the approach to slow down surface drying is a well-known one, but probably not practical in a larger production setup (and as mentioned by Jim and Dodgy Loner).

I've heard of a similar approach amongst kiln drying experts, and such things as sawdust, felt layers on the wood, and other things to keep the surface fibers of the oak wood from drying and shrinking sooner than the fibers below the surface. That theoretically will reduce surface checking and eventual honeycombing (internal checks that happen at the end of a fast drying schedule). Keeping mold in check would be a major concern with the sawdust, I'd think.
south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

solidwoods

Thats a real good way to make prime spalted Oak (no joke,, look at the value difference between prime spalted and plane old oak)

as far as drying:
Straight to a kiln. (thats a period)  unless is low value lumber,, crunch the #s cost of degrading lumber (remember someone paid to have it milled also, so that $ will be lost)   vs. kiln cost.  it ain't worth it

got no kiln?
stick it per normal in a proofed drying shed, then if its going indoors,, take it to a kiln (hey wait a minute,, were just right back at Kiln)
jim
Ret. US Army
Kasco II B Band mill
Woodworking since 83
I mill & kiln dry lumber, build custom furniture, artworks, flooring, etc.
If you mill, you'll be interested in some of my work in one way or another.
We ship from our showroom.
N. Central TN.

Swede

Thank U, all of U. I printed the anwers and gave to my customer. Told him he´d got a letter from America. He´s son  :D and said "thats the right one to give a letter in english". Next day the customer told me other in the family had translated for him.
We have got rain, rain and more rain here the last weeks so he has to buy dry sawdust (beside paying the sawyer). ;) The hay is wet, the sawyer is wet and there is more water in the dithes than in the spring. There was 6" water around my sawmill a couple days so I did a job in the workshop.
If there was a kiln I should knew where to stay! ;D

Thank You very much!
Swede.
Had a mobile band sawmill, All hydraulics  for logs 30\"x19´, remote control. (sold it 2009-04-13)
Monkey Blades.Sold them too)
Jonsered 535/15\". Just cut firewood now.

Thank You Sponsors!