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uncle duke

Drying fresh cut willow

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I couldn't find much about violin makers drying fresh cut willow wood.  I've read black willow can have 120% water while green.  Any ideas or opinions about drying the wood please.  I was thinking use the hot attic/cold attic drying for a few years.

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120% water? Hmmmmm. As my great grandma told me..."paper never refused ink"

My very best advice is to seal the ends, keep air circulating around fresh cut wood, the more the better, the longer the better, less important is added heat, I had some checking on my silver maple stored outside last year in below zero F temps. water moves....if the air is not moving the water will stagnate and lead to mold growth. I did not get any real checking on my willow blocks, it's pretty soft wood, might not be a big issue.

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All the wood I've ever seen stacked to dry (for various uses) has been 'layered' with lots of air space between layers.  Would willow be any different from any other wood?

 

And I don't get the 120% moisture either.  100% water is pure water...how do you go up from there? :wacko:

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All the wood I've ever seen stacked to dry (for various uses) has been 'layered' with lots of air space between layers.  Would willow be any different from any other wood?

 

And I don't get the 120% moisture either.  100% water is pure water...how do you go up from there? :wacko:

 

The high moisture content numbers are what made me post here- that is a lot of water.  So I tried finding where I found the high moisture reading from before- found another at 138 or 139% mc for greenwood.

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I couldn't find much about violin makers drying fresh cut willow wood.  I've read black willow can have 120% water while green.  Any ideas or opinions about drying the wood please.  I was thinking use the hot attic/cold attic drying for a few years.

Hi, the attic is probably the best place to season wood. The old woodworkers used the attic of their workshop with one end open to let air in.

 If you have plenty of wood  and prepared to lose a couple of inches at each end it is better to season the wood with the ends unsealed. The wood seasons a lot quicker and a lot better.

The biggest problem with willow is that the woodworms line up to get into it! The smallest amount of moisture and they get in!

If you keep your willow in a light dry place where there are a few spiders, the woodworm is less likely to get at it!

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The high moisture content numbers are what made me post here- that is a lot of water.  So I tried finding where I found the high moisture reading from before- found another at 138 or 139% mc for greenwood.

That would mean that 138% of the total weight of the wood is due to water content. Which would result in wood with negative weight once it has dried. ;)

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I started with "drying black willow for lumber" and found a few pages of different species of wood.

 

I'm out of good block wood Mr. Molnar and a neighbor just lost a good sized limb from the willow tree, just wondering "what if"- it's only 40 ft from my driveway.

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That would mean that 138% of the total weight of the wood is due to water content. Which would result in wood with negative weight once it has dried. ;)

Prepared the right way that stuff could work for a violin, right?  I have seen a few neck blocks recently, PeterKG  I think.

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Thanks , that I can wrap my head around... puts willow at 120% Dry basis ...to 55% wet basis ... meaning 55% of the weight of a fresh cut willow being water if I am interpreting the graph correctly ...... easily believable...

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I started with "drying black willow for lumber" and found a few pages of different species of wood.

 

I'm out of good block wood Mr. Molnar and a neighbor just lost a good sized limb from the willow tree, just wondering "what if"- it's only 40 ft from my driveway.

You don't need much for a life-time supply. Let it dry out in your shop then measure its density and see if that is good enough for you.

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"% water" is a vague unit, depending if you are talking about the percent by weight or percent by volume.  Violin wood (except for ebony), and wood in general, has a lower bulk density than pure water (that's why wood, unless it is absolutely soaked, floats on water), meaning for the same bulk volume of wood and water, the water will weigh more.  Dry wood contains lots of air spaces (is very porous), and when the wood is still green, most of the pores are filled with water, and in addition, there is water that adheres to the surface of the wood (green wood feels damp to the hand).  Also, the temperature at which the moisture content is measured affects the measurement, so a good piece of data always specifies what was the drying temperature. "Air-drying" is affected by the relative humidity;  drying at higher temperatures drives off more water, resulting in a higher percentage of water based on the weight of the dry wood.   I hope this helps.

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Most wood technical and engineering books describe wood moisture content as the percentage (by weight) of the wood which is composed of water. It is based on the weight of a sample, versus what that sample weighs when oven-dry.

For example, if a sample of wood weighs 100 grams, and the weight goes down to 90 grams when oven-dry, it is said to have had 10% moisture content. (simplified for clarity)

 

This method tracks well with equilibrium moisture content of most varieties of wood, and gives a good indication of the amount of weight they gain and lose with variations in the relative humidity of the surrounding air, when charts of calculations derived from weight versus oven-dry weight are applied.

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In my experience, "dry basis" moisture content has been more common for lumber. That is, calculated water weight (x 100) divided by dry wood weight, so green wood MC above 100% is common.

 

For the green willow, most important thing is to split or rip saw the pieces or it will split itself randomly. If you saw it into boards you may notice that the heartwood sometimes shrinks more than the sapwood. That may not be unique to willow, but I've never seen it with any other wood.

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I split my willow and stacked it to dry. Because of the amount I had, I wasn't concerned with losses due to cracking. I don't believe it's good to dry it too quickly, as this promotes cracks and splitting.

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I agree with CaptainHook's concept.  David, I assume you meant "it is based on the weight of water lost from a sample compared to the sample when it is dry".  In your calculation, the amount of water lost from the sample = 100 grams - 90 grams = 10 grams of water.  10 grams divided by the dry weight of the sample (90 grams) = 10/90 x 100 = 11.1 % = the original percent of water in the sample.

 

It is done this way (based on the dry weight of the wood) in order to have a uniform basis for the calculation from one sample to another.  Otherwise, the basis would be different for different samples that initially contained different amounts of water.

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Hey, Guys, this is somewhat out of topic but could a couple of you check  the thread of cello neck crack, which is down to the end of list with no takers?  It might be because I posted my problem at the end of a 2014 post on cello neck crack, and maybe no one wants to go back to that.  I didn't know where else to post it and would appreciate any suggestions for my problem --- I have posted some photos.

 

Thanks very much.

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The "standard" MC calculation appears to be the dry basis method, according to https://www.extension.purdue.edu/extmedia/FNR/FNR-156.pdf

 

That is the formula I use when calculating the MC of my wood... although I dry at above 105C, and in a vacuum... so my dry basis may be a bit lower than with the specified method.

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I couldn't find much about violin makers drying fresh cut willow wood.  I've read black willow can have 120% water while green.  Any ideas or opinions about drying the wood please.  I was thinking use the hot attic/cold attic drying for a few years.

 

The way I have always done it is cut in lengths long enough for cello linings. Then quarter it and square up the 2 cut faces on a planer and seal the ends. Stack and let air dry for year or more. More is better of course.

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In my limited experience the problem with white woods is always the blueing that can happen if not properly stack when freshly cut. 

 

I bought a log of rather nice poplar last year which I cut for one piece cellos backs. Looking thourgh them last week I noticed how some of them have blued, I guess it is a fungus. Not that I am too worried as I have used stuf with that kind of blueing before and it is pretty much invisible under varnish.

 

I would be very interested to learn what people do because felling season is coming up and I have a rather sexy maple tree selected and another poplar....

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I agree with CaptainHook's concept.  David, I assume you meant "it is based on the weight of water lost from a sample compared to the sample when it is dry".

Not sure I'm following you. I'm pretty sure I meant what I said, except that it would have been more clear and accurate if I had used the example of 110 grams wet, and 100 grams oven-dry to give an example of 10% moisture content, rather than using 100/90, and then "simplifying" (fudging) the moisture content to be 10%. You're right that the numbers I used would actually show an 11.1 % moisture content.

 

I think the first two pages of the article Don linked to explain it well.

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I would be very interested to learn what people do because felling season is coming up and I have a rather sexy maple tree selected and another poplar....

When the wood is first cut into blanks, good air circulation is important. Otherwise, the wood remains in a micro-environment of very high humidity, caused by moisture in the wood, which retards drying and contributes to growth of the "blue stain".

If it isn't windy, I direct a fan on the wood.

 

Another strategy is to cut the wood into blanks when the temperature is too cold to support the mold/stain growth. Ideally, by the time the weather warms up, the wood as lost enough moisture that will no longer stain. This may have been a large part of why there was once something called a "cutting season".

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