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I'm waiting for some new wood that entered the shop yesterday to acclimate. The relative humidity at the lumber yard is likely to be around 20-30 on an average cold day in Spokane. I keep my shop between 40-45.

My question is:

Is it a risk to resaw this wood now and then store them in a very flat condition under pressure rather than to wait 2 weeks for the wood to acclimate? I have numerous large flat pieces of metal and parallel spacing bars that will enable me to a very good job of storing them flat.

I'm guessing the answer will still be to wait a few weeks before I cut them.....but could someone explain why this is necessary. I'll be adding moisture....not subtracting.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

My thought if I wanted to resaw them today for some reason is that it doesn't mater if they are quartered. Quartered wood, other than splitting out in the pith, is pretty adaptable to moisture problems. If you have fancy figure arising from some wild grain, then you have the potential for havoc. you need to have the ends well coated and uniformly coated post sawing.

Why would it be worse to go about resawing now? It depends how even the current distribution of moisture is. You assume it is even, but different. It is always better to have real numbers than guesses. But if you are correct and it has not already started to absorb moisture, or loose it, then it can be an advantage to shift moisture when the material is thinner, rather than thick. If the ditribution is uneven, cutting it in half will unbalance the pieces, but it won't necessarily cause problems. But there is another side to this. If the wood is of a type to give trouble, and it is dimensionally stable in the current section, you risk revealing some new condition when you resaw it. I have split wood down the middle, wood that was straight to have it radically deform into a near circle. Of course that kind of reaction wood is not going to be pretty in any circumstance, but there are degrees. So if you had some problem wood, and added the moisture problem it might be too much, while it might have been fine if acclimatized in the larger section, then resawn.

For the most part, wood drying loses are at their worst during the initial conversion from the log. I will loose as much as 25% in the initial post cutting process, but that is almost always due to imperfect conditions of storage, it is just that imperfection is much more serious initially. For the following 4 years after the first 6 months I am likely to experience zero losses. Presumably your wood is already near, so you should expect less problems. Downside is you pay for wood like that, so any loss hurts.

I would be helpful to know what kind of wood, size, condition you have. It is dificult with no details.

I always store wood as open to air on all sides as possible, never between steel plates. I would sticker it carefully. If the moisture can't go quickly through the sides it goes through the ends, and that is when splitting occurs.

Another option is to vac bag it. I used to have a shop with free electricity, and I put something in the vac bag over night, every chance I got.

Resaw now and sticker. That's what I do....problems only arise when the outside of the wood was case hardened in the kiln. It'll acclimate to your environment faster this way anyway.

Go for it dude!

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Thanks!

The wood is Hard Maple and Peruvian Walnut. With both woods the grain is very straight. The walnut is quarter sawn and the maple is flat swan. The walnut pieces are basically 4/4 strips to be resawn to thin, .15" slabs. The maple is 8/4 strips to be resawn to .7" slabs. Both types average about 4" wide.

I guess my main thought on this is to facilitate the acclimation by exposing more surface while holding it straight. So the real question is: Can you trust thin maple and walnut slabs to hold their flat shape as they acclimate?

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

You'll be able to trust the Peruvian Walnut more than you can the flatsawn hard maple. The maple is likely to want to cup on you a little....but sticker anyway and don't worry about it.

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

That is a slightly different situation, since you are getting multiple pieces not just a pair, it would take some pretty odd circumstances to end up with terribly uneven moisture in resawn pieces. So you are probably out of the woods. In theory, with the flat sawn, the rings will tend to want to straighten out. So if they were tighter to the center on one side than the other, it would be best to make those slightly thicker to deal with cup. Of course if it came out of a great big piece, and the rings were essentially straight... Also look at either end to see how straight the rings ran, if there is near zero runout, all the better.

What kind of wood is the walnut? Does it have visible early and late wood, ie grain, or is it one of those tropical woods with nice colour, sometimes stripey, but not actual visual grain, so one really can't easily tell whether it is quartered or not

If I were concerned about the wood staying flat after re-sawing I would wait a few weeks or more, with both the Per. Walnut and the Maple.

30% compared to 45% is a big jump, quarter sawn or not. At 4" nothing's going to cup much but I'd bet you'd get a bow in the length.

I know what I'm saying here is opposite of previous posters. I'm just reflecting back on my experience of over 30 years working wood. Depending on many things, it may stay fairly flat but I wouldn't want to risk it regarding instrument building.

I like you keep my shop about 40-45% and most wood I resaw will move just because of the RH differential from opening the plank . . seldom do I have any real problem . My MO is simple , resaw and then clamp the cut wood for a few days . Then I sticker that and clamp. I try and keep the sets together and sticker with a 3/4 inch stick . I often clamps 20 sets to a stack and pull out what I need when I need it .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

As the others said you can resaw now. Be careful with that metal. Is it painted or coated? If there is signifigant moisture in the maple it will oxidize and you'll get blue stain.

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CVT Inc.
A tour of our shop (Somewhat outdated)
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I recommend clean dry pine or spruce for all stickers. Use the metal for weight on top of the stack.

_________________
CVT Inc.
A tour of our shop (Somewhat outdated)
My Personal eBay profile. BCWoodBug

I'm in the re-saw now camp. With 8/4 wood, waiting a few weeks isn't going to do much, Once down to .7, they'll reach equilibrium much faster. Definitely sticker though with weights - that maple could very well cup.

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http://www.birkonium.com CNC Products for Luthiers
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I do alot of resawing and find that any wood made thinner by resawing tends to want to move so i always clamp them to stop any movement until i use them.

Good advice guys,

I'll saw it soon and sticker it all.

It's going to be used to make about a dozen neck laminates which I intended to stock and cut a few at a time.

Based on your advice, it sounds like a reasonable plan to cut it and let it sit a little while before gluing up the blocks. It also seems like a good plan to think hard about some simple clamping fixtures soley for this purpose.

Thanks again!

_________________
I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

one very efficient way to clamp is to use tie down straps or bar clamps . My preference is harbor freight bar clamps .. they are not very expensive and are stout enough for the job.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I was using 1x pine for stickers (ripped to final dimension of 1/2" x 3/4"). David Borson gave me a tip which I found very effective. Namely, use 1/4" or 3/16" thick brown fiber board and for sticks and clamp using rubber bands. My bottom and top sticks are the stout pine sticks (1/2 x 3/4) with the fiber board sticks in between. The rubber bands exert plenty of clamping force. Here's some shots:
















This gives an option of storing a bundle of stickered wood on end which is very space efficient and allows easy retrieval from several different batches. No wasted space from bulky clamps or thick sticks.