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BillyReeder
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Drying quality article

Has anyone read the article on page 22 of this months sawmill and wood lot management magazine. It's got me confused on a few things

Post Oakie
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Just got it yesterday.  The complexities of different drying rates between longitudinal, tangential, and radial, along with juvenile wood can drive a guy bonkers!indecision  Any specific questions or comments?

BillyReeder
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The main thing in question was the comment about sawing parallel to the bark instead of the pith. I was under the impression that you always want to level the log according to the pith, especially if you have a swell at the end. 

eddiemac
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If you have a clear log (one without knots showing), the highest value lumber can be obtained from the outside boards by sawing parallel to the bark.  Of course, this creates problems when you get near the center of the log   ---   your remaining board or post will be a non-rectangle.  But the center of the log yields low quality boards anyway due to the presence of the early branches of the young tree.  If you are sawing posts or ties, you need to center the heart (unless the log is big enough to saw well outside the pith).  If your aim is to produce grade lumber, sawing parallel to the bark will result in the most valuable product and avoids problems with slope-of-grain. Construction lumber is probably more efficiently sawn pith-centered, especially in softwoods.  On my hardwoods, I like to put the worst side up, saw parallel to the bunks, flip the log 180 degrees, and then make a cut which turns out to be parallel to the bark and, if all goes as planned, yields a nice clear board on the following cut.

BillyReeder
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Ok. That brings up my next question. my target customers are cabinet makers and furniture makers. I know several who are behind on orders due to the fact that the can't get quality lumber in my area. One in particular  has to order lumber from the east coast. I've been told that they prefer heart wood. Can you explain this a little better and maybe a little bit about juvenile wood. It's my impression that heart wood is from the center of the tree and juvenile is from a young tree. 

eddiemac
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I would think what they mean when they say "heart wood" is that they don't want the outer sapwood, the lighter colored band next to the bark.  Otherwise it doesn't make sense to me.  I don't have a good understanding of juvenile wood, but think it is the earliest growth close to the stem (around the pith).

r.garrison1
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Having been a cabinetmaker, one thing I would appreciate is a visit to their shop.

Stop by, ask what grain they want to see. Maybe take a couple smaller samples of some cuts that you've done.

Even if you don't give them exactly what they want to start, if you seem willing to work toward what they want, they will become loyal customers. 

One big thing; keep the schedule. When I was hanging cabinets, we started them in the shop, sometimes had part of a crew still building the base cabinets when I went to hang the upper ones. We had access to the house after the HVAC guy and electrician had the house heated and power roughed in; sheetrock was done, painters sometimes working in the house while I was.

When I was finishing up, the plumber was putting in the kitchen sink, the carpet was going in, and the other finishing stuff was happening.

If we missed the schedule by a couple days, it caused headaches for a handful of people. Don't be the guy that makes a cabinet maker late, he won't forgive you.

Post Oakie
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I've got to admit, the mechanics of sawing parallel to the bark has me baffled, too.  I understand the idea behind it, but the cant has to be supported at an angle to the bed, so do you leave the toe roller up, mill down to the center, rotate the log cut the tapered piece out of the center, then roll it back and cut straight down?  That's the only way I can see to have the cant supported flat on the bunks.  Eddiemac, if you're doing this, I'd love to get more details on how you do it.

eddiemac
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I have done it, but can't recall the exact steps.  I think I sawed with the small end raised, took some flitches, put the toe boards down, rotated 180 degrees, did the same procedure and put the toe boards down again.  At that point, you can cut from the center of the small end to yield a uniform thickness on the bottom half.  When you do that on the other half, you are left with a core that is pointed on one end and thick on the butt side  -  firewood.  In between these steps, I may have been rotating at 90 degrees and either cutting parallel to the bark or not, depending on the quality of grain.  I now have some very wide trapezoidal oak boards as proof of full with-the-bark sawing.  I think I'd just read an article by Gene Wengert in "Sawmill & Woodlot" about the technique and wanted to try it.  Don't waste your time on poor quality logs.    

eddiemac
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On second thought, I may have cut flitches down to the center before going on to the second half.  It's not something I do often, as high quality logs are hard to come by.

BillyReeder
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Well it's got me confused. Like I said earlier I'm wanting to sell to cabinet and furniture makers but also wanting to make flooring as well. I have no problem getting big logs as the local big mills won't take anything over 28 inches and our tree surgeons can't sell to the big mills. We had a bad rash of timber theft a few years back and the big mills will only buy from logging outfits. However I've got it set up so the tree surgeons can dump there logs and brush on my property as refuse and don't have to pay a disposal fee at the local land fill. Right now I have 93 good logs ranging from slash pine to red oak with some cypress, sycamore and black cherry just to name a few. They range from 16 to 45 inches. I'm just waiting on my retirement to be able to order my mill which is 10 days away. Could the center of the logs be made into flooring? I know I'd have to work around the pith but it's got to be able to be used for something other than firewood. I've searched the Internet and forum for videos explaining some of theses questions but there's not much I can find out there. I'd be willing to bet that if someone with enough experience made a video or a series of videos there would be people willing to buy them. I know I would. 

eddiemac
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Billy, alot of things will become obvious to you as you get some experience sawing.  I'm sure many of us are envious of the logs you're getting.  I know I am.  (The brush though, not so much  -   be careful that situation doesn't get away from you).  As for flooring, I'm no expert, but the center of the log yields quarter sawn lumber which is perfect for flooring if it doesn't contain knots.  And short pieces can be used.

BillyReeder
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When I order my mill I'm gonna order an extra bunk or two so I can cut the shorter logs. As far as the brush and tops I was thinking about getting a chipper and chipping what I can and selling it for mulch. What ever can't be chipped or sawn for lumber I'll make fire wood and sell. I've also thought about a wood fired kiln but haven't been able to find any plans for it on the Internet. My wife and I got the idea for this business because we know a few cabinet makers and such that can't get quality lumber locally and hardwood flooring is so expensive, yet we constantly see Logs going to the landfill or being burned or see them left to rot at logging sites simply because they won't mak a full truck load. I guess it could be called a green business since it salvaging what would otherwise be wasted. If that makes since at all. 

r.garrison1
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You have the roots attached? Cut that stuff into blocks, dry it slowly,. and turners will love it. A lot of interesting grain happens where tree hits the ground..

sawdoc
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Juvenile or Sapwood and Heartwood

Here are a few quick notes on the anatomy and physiology of trees. Just under the bark is the cambium layer, which has two main functions: First to produce new bark cells to the outside and new wood cells to the inside, and second, to transport nutrients produced by the leaves down to feed all living cells in the tree, including the roots. A simple girdling of the tree starves the roots and the tree dies. Each year there is a new layer of wood cells produced that we call an annual ring. We can age a tree by counting the number of annual rings that have been produced. Similarly, the older a tree gets, the thicker the bark.

The wood cells that are produced to the inside have two major functions: First to transport water and minerals up the stem to the leaves to support photosynthesis, and second to provide support for the stem. The cells that make up this annual ring only live for approximately 20 years and then they get clogged up from all the impurities in the transported water, and they die. When they die, they generally develop a darker color. These dead wood cells are called “heartwood”. So generally speaking, each year there is a new layer of “sapwood” produced, and another inner layer of wood cells dies forming more “heartwood”. The bulk of a mature tree is made up of dead wood cells of the heartwood, and these cells do little to support the tree. That is why a hollow tree can survive for centuries.

The amount and color of heartwood varies between species. Some trees, like walnut have significant differences in the appearance of sapwood and heartwood with the sapwood being creamy and the heartwood very dark. Also, because the sapwood contains living cells it tends to be softer than the dead cells of the heartwood, and the two may react differently when machined. It is the darker, more stable heartwood that cabinet makers are often fond of.

On the other side of the coin are trees like sugar maple, which greatly retards the formation of heartwood resulting in the majority of the stem consisting of sapwood. Maple heartwood is bland in color and highly susceptible to rot, but it is the light uniform color of the sapwood that cabinet makers value.

For more information, visit your local library.

Sawdoc

r.garrison1
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Very good explanation! yes

BillyReeder
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And very good info. Thanks everybody. You've all helped a lot. This info will help me decide what to to with which logs. 

Post Oakie
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Great explanation.  That's why you're the doc!