Slow seasoning vs. Quick drying

[zenmonkeyman]

Somewhere in the Bowyers' Bible series (Vol 1 I think) somebody (Tim Baker I think) debunks the slow seasoning myth.  Does everybody agree with him?  Is a green-reduced 3wk stave as good as a 2-3yr bark-on seasoned stave?

Here's where the question comes from.  Last year I made a coupla serviceberry bows, dried as fast as the air in my apartment could do it.  There was hardly any heart wood.  Just the other day I started a serviceberry stave that I'd left with the bark on for a year.  It's almost ALL heartwood!  There's only a paper-thin white skin on the outside.  Does the conversion from sapwood to heartwood continue in an unsplit, un-de-barked stave?  Has anybody else seen this with other woods?  Or is my heartwood stave just a coincidence?

[aaron]

ok i'll take a stab at this...
i think there is still dabate over drying times, but my opinion is that it doesn't matter how long you take to get to the desired moisture content. that is, fast drying is fine as long as the wood doesnt check or otherwise get physically damaged by the changes in dimentions accompanying drying. I think the prob with quick drying is that people migt not get it dry enough- mabe its dry on the outside, but inner moisture creeps out and leads to set.  some woods i use (vine maple) seem to dry quickly and without much set from use. others (black locust, ocean spray) cannot be dried quick due to cheaking (splitting)

also, i doubt that heartwood conversion continues after cutting (maybe a little, like one ring worth max). this is just an educated guess...

[PatM]

I disagree with Tim. Not that quick drying doesn't work and have its place but stuff happens during seasoning that does give  small benefits over quick drying.
 Over time, particularly if wood goes through the moisture cycling of a few seasons the wood gradually shrinks more than it does upon initiial drying. That equals increased density and stability.

[sailordad]

im gonna have to say that long term easoning makes for better wood
i was given a hhb slefbow that a guy made,it was dry for a year when he tilered the bow
it was tillered to about 55#,he shot it or a season,then started making glass bows and this stayed in rafters of his garrage for near 10 yrs
thats when i got the bow
it now pulls over 70#,i can just barely get it to full draw
eventually im gonn retiller it

[Pat B]

I think whitewoods handle quick drying better than osage, mulberry and locust(and a few others). These oilier woods need time to cure out well. IMO  I built a 60" osage static recurve a few years ago that was two months off the stump. Even though it worked like dry wood it developed more set than usual and fretted in one limb. I very rarely get frets in osage. After a year I repaired this bow by grinding down the belly and adding an osage belly lam and retillered it. Today it is a great shooting bow...I just didn't let the wood season long enough before stressing it in the original build.
  I do think there is a difference in well seasoned and just dry wood.

[Del the cat]

To me it's very simple, it depends on how much you value the wood.
I take care with my Yew* as it's in short supply, but I'll try quick seasoning with stuff I can get hold easilly, like Hazel, which I've found seems to respond well to quick seasoning on a radiator.
So experiment, but only if you are willing to accept the possible result.
Del
* I have put Yew on my magic radiator but only after it's already had 9 months seasoning as a much reduced stave and it's been de-barked for a while.

[Pappy]

Pretty much what Pat said,I like seasoned wood better, Don't seem to have as many suprises
when tillering.
    Pappy

[DarkSoul]

Zenmonkeyman, it is absolutely impossible that sapwood turns into heartwood after it has been cut. Sapwood is defines as the outer layer of wood in a tree that contains living cells and is responsible for water and nutrient transportation. Heartwood consists of only dead cells, where the vessels have been blocked so they no longer transport water or nutrients. Upon felling a tree, the trees is basically killed, which stops the transformation of sapwood into heartwood.

Over time, particularly if wood goes through the moisture cycling of a few seasons the wood gradually shrinks more than it does upon initiial drying. That equals increased density and stability.

Could you elaborate on that, please? I see no reason why slowly shrunk wood has shrunk more than quickly shrunk wood - which is basically what you are saying. Have you ever measured a stave to see the difference in pre- and post-drying dimensions?


What I think often happens, is that people "quick dry" a stave. They place a chunk of wood on the radiator or in a hot car, and they just expect it to be dry after three weeks or so. Most people just assume it's dry by then, without actually verifying. But the inside of the stave, the wood furthest away from the outside of the stave, may still contain some water. This migrates through the wood as the bowyer finishes the bow, or maybe even after he's already finished the bow. The wood is basically still too moist, causing set and robbing cast.
I would advise people to check the moisture content of the wood after (or better: during) quick drying. Put the stave on a accurate scale once a day.When the stave stops losing weight for a few days on end, you know the wood is dry. Or: buy a meter with pins to actually measure the MC of the wood. Scrape away some wood so you can measure the core of the stave, which dries slowest.

I'm still a believer of the quick drying method as proposed by Tim Baker. I just think many people overestimate the process, byt leaving their stave too thick, putting it in a less than optimal drying place, and not checking the MC of the wood.

[Eric Garza]

I think quick-drying a stave can work, but it can also fail.  When I want to season something fast I will reduce a stave to near-bow dimensions while keeping it as wide as possible.  I have five white oak staves quick-drying right now, all are 3-5 cm wide across the back and have been reduced enough that I could brace them if I cut nocks in.  These are very short staves (100-110 cm long) since I make short bows, so the wood is less than 1/2 inch thick.  I am drying them under a fan until the reach a constant mass for 3 days (weighed on a grain scale, so I can measure their mass to 0.1 grams). 

I expect this method will work well for quick drying, since the staves are very thin.  If you had a large split stave with the bark on you will not quick dry it.  The wood needs to have one dimension that is very thin, so that moisture doesn't linger deep inside the stave like Pat mentioned.  This is a huge problem for lots of folks who attempt to quick-dry staves, as when you shave off the outer layer of wood while tillering the inner layers that are exposed are still green and will take lots of set, and also might cause the bow to warp as they start to loose moisture.

[Holten101]

There is quick drying, and there is quick drying....avoiding checks is paramount, but other than that dry is dry in my mind when it comes to wood quality.

People who cut a trunk and set it aside for 10 yrs are basically just waiting for shavings to dry....I cant see any reason at all why a roughed out bow cured for 4 months (depending on wood type ofc) does not have all the qualities of a trunk of the same wood type dried for 10 yrs (as long as.

I would love to see any kind of documentation for the opposite, and I will review my opinion if the top 10 flight shooting record holders avoid quick cured wood at all costs;-)

Cheers

[Del the cat]

@ Holten.
I couldn't agree more, there are some people who think it's clever to leave a whole trunk of Yew for umpteen years.
The more you reduce the wood the less internal tension will be present and the quicker it will season. Of course some wood is better with the bark left on to stop it drying too quick, but generally a quartered log will be less likely to split than a whole log or a half log.
Del

[toomanyknots]

"People who cut a trunk and set it aside for 10 yrs are basically just waiting for shavings to dry"

Tru that. The best way I think is to move slow at first to avoid checks, to take a stave down to a roughed out bow in stages to avoid checks and twisting. If you rough the right wood out too fast you can ruin the stave with huge checks or it might twist right up into a pretzel. So it's better to spilt/quarter the stave and take the bark off. Leave inside in a place without too much heat/sunlight after sealing the ends, but not somewhere damp or some woods can mold. It's better like inside in a hallway or a room in your house, not in a corner or somewhere they will mildew. Wait about a month. Hack it down to very fat dimensions for a bow, but don't go too far or woods like osage can belly check for days. Wait about another month. Hack it down to a roughed out bow and wait a good 3 or 4 months after that.

[PaulN/KS]

I am a take it slow kinda guy myself. I'll cut a log then let it sit in the barn, with the ends sealed, a few months just to see where that first end check shows up. From there I'll split it in half and let it sit for awhile before I quarter it up.
I figure that since ya gotta wait for a tree to grow, I might as well wait for it to dry...

[zenmonkeyman]

Heartwood is just dead sapwood. Killing the tree stops the conversion process.  But really, how do we know that?  Heartwood is just sapwood that is no longer recieving nutrients due to its distance from the cambium nutrient-transferring layer.  Who's to say what else is involved in the process?  I'm guessing moisture and time are the other factors, and if moisture stays high due to the bark slowing the drying, why wouldn't the sapwood turn to heartwood?  Has anybody ever cut a dead tree and found sapwood?

[George Tsoukalas]

Sapwood and heartwood are both dead. The only living part of the tree is the cambium or inner bark. Sapwood does become heartwood but only while the tree is alive. I've made slow dried bows and quick dried bows. Haven't seen any difference. I would not quick dry black locust.  I'm afraid of checking.  Jawge