Artificial seasoning of wood

[Stick Bender]

I have a couple Osage staves really double staves probably make 4 bows I got from Clint I have them stored in my rafters Where it gets on average 103 F in the summer I coated them with 4 coats of spray shellac & 2 coats of spray poly I take them down every couple of months and see no checks there taking nice reflex , I really dont no if there is a way to speed seasoning other then time I have another sapling stave with bark on thats suposed to be 20'years every time I pick it up the bark is so dry it comes off in chunks I have another thats 25 yrs old that is dark like walnut maybe the color change indicates seasoning ?

[osage outlaw]

In my opinion there is difference between seasoned and dry staves.  A stave can be decades old and still hold too much moisture if they were stored in a humid or moist environment.  I've roughed out bows from staves over 20 years old that were stored in my garage.  I put them in my hot box for a while and got drying checks that weren't there before. 

You can take a fresh cut stave, rough out a bow, and carefully speed dry it.  You can get it to a point where it's dry enough to make a bow but I don't think it will perform as good as a stave that is seasoned and dry.  I believe that's the combination that makes the best bow wood.  I rough out a lot of bows and store them in my house until I'm ready to make a bow from them.



Badger, do you think one long heat session or cycles of heat would be better at speeding up the seasoning of a stave?  What if you were able to add pressure to the heat?   I'm not so sure it can be done. 

[Badger]

  Funny you said that, I was also thinking pressure and heat. No idea how much pressure. Maybe if we understood better exactly what takes place while the wood seasons we would have a better idea how to duplicate it. I think things like lignin and latexes in the wood tend to harden up and bond with attaching fibers. maybe the volatiles are leaving very slowly, if that's the case maybe heat and vacuum.

[Stick Bender]

They sell vacuum bags and hand pump for laminating or veneere at some wood working stores or net you could just throw the stave & bag in the hot box it's designed for the heat !  Or they have the storage bags you can hook to your vacuum at the big box depends how much of a vacuum you want  & I don't know how high of heat those would take !

[Morgan]

Vacuum lowers the boiling point of water. I think at -29 the boiling point is 72° but I may be mistaken. I know that vacuum kilns exist but don’t know much about them. At work, we have vacuum loading pumps that deadhead @ -40. I’ve thought about making a simple foot long vessel out of 4” threaded iron pipe with a cap on one end and bell reducer and ball valve on the other. Idea is to place in the pipe a fresh off cut piece of a bowstave split and some desiccate and pull all the vacuum on it I can. I would like to see how quickly it dries this way ( I’m thinking very ) and if there’s any adverse effects as seen in other drying methods. With a small test sample such as this, would there be a way to test if the wood is changing as seasoned wood does?

[PatM]

Every time this topic comes around I mention the process bamboo flyrod makers often use to make their rod blanks more stable compression resistant and stiffer.

 Pretty sure the answer is there.  Originally they even used the same essential compound that is found in heartwood.

 All of the points are covered.  Types of resinous compounds, heat, pressure, cure time etc.

[PEARL DRUMS]

Osage outlaw gave me a small stave at Marshall that was split from wood supposedly drying for at least 25 years. I accidentally left it in my vehicle for the next few days where it was 90+ outside and it checked like crazy. I’d be cautious with nice staves and that high heat.

Exactly my thoughts doc.  A fresh stave left in 200 degree heat would be a complete mess in a day or so. I got a log from Clint several years ago. I split out 8-10 staves and put them in my garage, 80-90 degrees in the summer. In a few days they were all firewood. Side checks and back checks throughout. The best way to cure/dry osage IMO is to leave it somewhere dark and around 50-60% humidity for a few years. Then rough it out and sit it on an AC/Heat register for a few weeks do get it just a bit more dried out. I love my results.

[Jim Davis]

Slow drying and aging is great. The fast-dry concept was born of the desire to hurry up and start making that first bow.

OTOH, I have several bows that lost draw weight over a few months without gaining string follow. No idea why.

[bushboy]

As a side note,I'm starting to think that elm staves stored in my shed over winter and subjected to up to-44f seem to be better bow wood than others that I stored inside in the past!kinda like a freezer burnt steak effect!

[Badger]

  I agree with most of the above, I haven't seen any substitute yet for simply aging the wood. I would be nice if we could find a way but I imagine we would have to know what was happening during the aging process before we could figure out how to replicate it.

[Selfbowman]

Those Okies would figure out how to make a six ft long microwave. Now that's thinking out side the box.
Arvin

[Morgan]

Those Okies would figure out how to make a six ft long microwave. Now that's out side the box.
Arvin

[vinemaplebows]

Those Okies would figure out how to make a six ft long microwave. Now that's out side the box.
Arvin

Do it all the time works great!

[Selfbowman]

Vinemaple are you growing any extra ears or such? I have heard of cutting a hole in each side. Is that what y'all do. And will it dry or season a stave?  Arvin

[Springbuck]

I haven't seen any substitute yet for simply aging the wood. I would be nice if we could find a way but I imagine we would have to know what was happening during the aging process before we could figure out how to replicate it.

  Despite how much I value the opinions of so many experienced bowyers on this site and over the years, I am still more prone to dismiss the effects of "seasoning" vs drying, for MOST species, in MOST situations.  My own experience mirrors the line from Torges' books..."Cast comes from dry wood properly tillered" and I still think the dogma that bow wood MUST be seasoned slowly for years to even MAKE a bow is nonsense.

  However, I'll add some interesting links about a recently developed industrial process that hardens and strengthens commonly weak woods like poplar a RIDICULOUS amount.   So chemically changing wood must be possible, and thus, I must admit that there COULD be SOME natural process that does the same.

  My first thought is that this "seasoning" effect may only exist in some species.  EVERYONE here has more osage experience than I do, but I have not noted improvement in elm, ash, maple, etc. that I let sit around for years before working, even in good conditions. Quite the opposite, in fact.   So maybe osage, yew, and some other very resinous tropicals are affected?  BL heartwood? 

  The problem is we would really have to take a large sample of sister billets, dry them to exactly the same MC, make exactly the same bows, and then leave one to season for however many years, then shoot it again.  Then we have to measure set, cast, cast per mass, etc...

  Now, I must admit that it never occurred to me there might be substances within wood besides water that remain liquid, pitchy, or latex-like that may harden over time.  Makes the most sense to me that if this is happening, those may be the culprit.

Almost ALL chemical reactions are accelerated or catalyzed by heat, but perhaps the "magic bullet" of belly tempering does this as well or better than long-term kilning would.   I know for a fact that over-drying wood will quickly take back any ground you may have gained.

NOW, here is the funny part to me.  These articles discuss a process that results in extrordinary strength and hardness of wood by compressing it, BUT!!!!!!  here they chemically REMOVE some of the polymers, including some, but not all of the lignin.

https://www.smithsonianmag.com/smart-news/chemical-bath-and-strong-squeeze-makes-super-dense-and-strong-wood-180968117/

 https://www.nature.com/articles/d41586-018-01600-6

https://www.sciencealert.com/new-super-wood-stronger-than-steel

https://www.popularmechanics.com/science/environment/a16758876/chemical-treated-super-wood-steel/

I can't find an article right now, but I read something else about a similar chemical process, but with less compaction that still tripled the strength of common woods.

And, finally, this product is so volatile (dries so fast) that it doesn't penetrate wood deeply, and I haven't figured a way out yet to let wood just bathe in it.  But, I will, and I'll use it on just the bellies of bamboo and some white woods.