Heat-treating in the old way?

[paulsemp]

I have cut some dead standing Osage where the bark was still somewhat on. There was no sapwood. All hardwood all the way up to the bark. There may be something to whats being said. I never thought about why that happened but it truly confused me when I saw it

[sleek]

I have cut some dead standing Osage where the bark was still somewhat on. There was no sapwood. All hardwood all the way up to the bark. There may be something to whats being said. I never thought about why that happened but it truly confused me when I saw it

I have experienced the same with tornado downed trees. I cant say if it happened before or after the storm, but they had been dead awhile. If anyone knows of any dead standing osage, check it for sapwood please.

[Marc St Louis]

A long standing member here (Glenn Doane from VA) sent me a couple billets from a dead standing Osage, this is quite a few years ago.  It was lower density wood but was it ever elastic.

[sleek]

So it was low density and very elastic? Did it have sapwood, or was it already chased down?

[Strichev]

I've read that sapwood doesn't differ from heartwood when it comes to primary components of cell wall (cellulose, hemicellulose, lignin, glucomannan, xylan). Cellulose microfibril angle also doesn't change. The observed difference in properties is therefore attributed to extractives deposited during the transition from sapwood to heartwood. Primarily polyphenols and flavonoids. These compounds are thought to interact with the cell wall and change its properties.

A dead tree shouldn't produce/deposit these compounds, sapwood should remain in place after it's dead. Unless sapwood transitions to heartwood in its entirety shortly before the tree dies (or during cell death!) we should be able to see it.

Now, any method introducing similar compounds during heat-treatment should stand to reason if the properties of heartwood are indeed due to extractives. Maelming and similar techniques might be effective. I wonder if those " revolutionary™, moisture proof fire dancer™" bows don't use something similar.

[PatM]

 The changes are due to extractives.  I wouldn't be at all surprised if extractives can still diffuse out into the sapwood in a standing dead tree.  The pathways for them to move is not closed after death.

 Often trees which die standing seem to have more heartwood anyway, presumably as a reaction to whatever ailed them and made them die.

  It's worth noting that phenols are important in the manufacture of plastic substances like Epoxy and phenolic resins.   Seems quite likely that natural phenols in woods like Osage naturally form a more plastic like compound in cell walls over time in curing wood.

[Marc St Louis]

There was no sapwood in what I got, don't remember if I had to chase a ring

[Deerhunter21]

did the sapwood rot away? i know the heartwood wont, the sapwood will.

[Strichev]

did the sapwood rot away? i know the heartwood wont, the sapwood will.

Guys have found trees with bark still on but no sapwood. If the sapwood rotted away so would have the bark.

[Ringeck85]

Guys I just want to say that I've found this thread discussion fascinating. 

I doubt there is any textual information directly referring to native Americans heat treating their bows in the earliest colonial explorations/conquests of the Americas, but I have a few translated works handy (from Spanish/Portuguese) of the Narvaez (1527ish?) and De Soto expeditions (1539-42?), and they had all sorts of interesting things to say about native archery (while some accounts were probably at least a little exaggerated). A common theme in these accounts was that the European explorers/would-be conquerors were apparently very impressed by their skill and strength (this is in the S.E., called "La Florida" overall by the Spanish, and pre-1600s).  And this was all before the 1545 sinking of the Mary Rose, so some of them would have been aware of English archers somewhat. 

I'll give that another look through and let you know if I find anything.  (Otherwise I'll post some notes on what I've found/some of my theories in another thread since this is a barely related tangent)

[willie]

Guys I just want to say that I've found this thread discussion fascinating. 

I agree.

Marc,

the discussion about aging and drying is becoming intertwined once more.

Just curious what your present thinking is about what is happening when a bowyer heat treats your way.

is there more happening to the wood than what would happen if the same stave was aged well?

or dried for an extended amount of time?

thanks 

[Marc St Louis]

Guys I just want to say that I've found this thread discussion fascinating. 

I agree.

Marc,

the discussion about aging and drying is becoming intertwined once more.

Just curious what your present thinking is about what is happening when a bowyer heat treats your way.

is there more happening to the wood than what would happen if the same stave was aged well?

or dried for an extended amount of time?

thanks

Well for one thing.  The high heat used for heat-treating will caramelize sugars in the wood and caramelized sugar is more resistant to water that dried sugar, what you would get from seasoned wood

[PatM]

Lignin in wood is a complex subject and its synthesis isn't even understood at this point.

 https://en.wikipedia.org/wiki/Lignin

[meanewood]

A while back, I made a 85lb longbow from a Yew sapling that had a diameter of 36mm at the middle of the stave.
 
All that was required to reduce and tiller the bow 400mm -500mm from the center was to flatten the belly.

This still left a sapwood belly apart from the upper and lower section of the limbs where the heartwood core emerged.

I was wary of heating this sapwood belly but some string alignment was needed so I went ahead.

The surprising thing is the yew sapwood became so hard, I could not stamp my 'mark' at the arrow pass.

So not only could yew sapwood hold up to belly compression but when heated it became harder than other yew heartwood I've heat treated in the past!

Has anyone else had this experience with yew sapwood?

[Bryce]

I gotcha Bryce, I’m not saying it’s better to do it fast...just faster. Just like there’s quick drying  maybe there’s quick curing too. Hopefully I’ll be in less of a rush when i haven’t been building bows for less than half as long as you’re drying staves.

I hear yah man.   I’ve been looking and experimenting, but I’m only a young buck and have only been at it 10 years, may sound like a long time but it’s nothing compared to some on this board.
But the more I try the more I think wood especially woods like yew with great sap content are like a well made wine. Just needs time.