Wood dehydration query?

[sieddy]

Hi all Today I'm pondering how a cut log/branch left in the round dehydrates when the bark is left on and the ends are sealed. Any insight or thoughts would be appreciated.

[DC]

Well, nothing is completely waterproof. That said, I had a piece of Black Locust sealed up like that and after a year I peeled the bark off and it was all mildewy and soggy inside. Better off to split/saw it and let the water out from the middle.

[simson]

which wood?
which diameter?
split or whole sapling?

I work my stave down to nearly dimensions after some months (harvest) and let them season mostly a min of 5-7 years.

[sieddy]

I cut a Yew branch a year ago, it is about 4" diameter and 6.5' long. but I wasn't able to bring it home so I sealed the ends with pva and I left it under cover and off the ground. It's been a busy year so I've only just been able to go and get it and it's nice and light so I'm hopeful its well on its way to being seasoned. Fingers crossed!
So I guess the bark breathes somewhat and allows the moisture to evaporate.

[DC]

My climate is much like the UK and I find that Yew won't dry enough outside. Split it, rough out a bow and store it indoors until the weight stablizes.

[sieddy]

Yes I aim to give it a good few months split inside. But I feel more confident it won't prop twist on me now. I had that happen once to a beautiful Yew stave which had sentimental value, after I split it straight away. I was gutted! 

[PatM]

Bark is not even close to waterproof.  It's not much different from wood.

[sieddy]

That's really interesting. I thought barks main job was to keep water in the cambium.

[Strichev]

Suberin in the bark reduces water loss.

[Philipp A]

Since I use HHB for my bows I start first by sealing the ends of the logs right away after cutting. Then I half or even quarter them with my chain saw (HHB doesn't split well) and then use a band saw to further reduce to the ultimate number of staves I can make from a log. I then debark the HHB since I have found that if you leave the bark on too long you some times end up getting discolouring of the wood. I then store the wood in my shed piled in a dry spot with slats in between the layers so the air can get to them. I keep them away from the windows so I don't get direct sunshine on the staves.

I am not an expert in other woods but I wouldn't think it be much different.

[sieddy]

Sounds like you got that process down to a Tea Phillip. Do you not have any problems with the stages warping once their reduced down?

[Philipp A]

@sieddy: I have not had much of a problem with the staves warping after quartering them. It might be different with other woods. I just have not had much success in leaving the bark on too long. I have tried it with some staves and I end up getting grey spots on the back once the bark has been stripped and it seems to go a bit further into the grain of the wood so its next to impossible to remove without taking layers off the back.

[Pat B]

Leaving the bark on the back will slow down the moisture loss which will help prevent checking. You do have to consider insect damage as most of the destructive insects lay their eggs in the bark.  Removing the bark while the stave is fresh is easier than later but you have to seal the back. Split staves can loose their moisture from the split sides without causing damaging checks. If the belly does check they are usually removed as the bow is built but even if not they aren't as dangerous as back checks. And, checks in the back are generally more of a cosmetic problem unless they run off the back.