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DRP
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# Posted: 29 Apr 2025 08:17pm - Edited by: DRP
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Some random wood related stuff from today. I've replaced our old french doors and needed to make new trim, the new doors are slightly smaller than the old so I dug out some oak from the barn attic. The first pic is of freshly finished red oak and 30+ year old. Same finish (Waterlox). The trees were within 100' of each other. The difference is just time, sun and oxidation.
The second pic was from doing some cleanup of the old collapsed house on the neighbor's property. The previous owner was a packrat. I haven't seen any in a few decades but celotex, a fiberboardish wood fiber sheet with an asphalt coating was the go to sheathing from my youth through about the 90's. Around 2000 is when the IRC and the ever expanding wall chapter of the code kicked in.
Edit; Looking at the oak pic, the wood is flatsawn, roughly tangent to the rings. The "chicken scratches" you can see in both sticks is the end on view of medullary rays, the radial, in/out transport cells of a tree. They are obvious in the oaks, white oak having the largest.
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DRP
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# Posted: 30 Apr 2025 04:28pm
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After mentioning the rays yesterday, the middle board in this pic popped as I walked by today. That is quartersawn, like a spoke on a wheel, a straight radius line from heart to bark. So in that board the saw passed in line with the medullary rays and shows them off. They are only a cell or two thick, multiple cells tall and quite a few long. They also tend to flash as the angle of light and sight changes, the tiger eye effect, "chatoyance".
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DRP
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# Posted: 1 May 2025 10:39pm
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I was cleaning up the computer and saw this pic. Its a scan from an old Forest Products Labs publication. Sort of newsprint quality but they were testing the thinking that high rings per inch counts is an indication of some type of higher quality. If strength, stiffness, and fastener capacity are the qualities we're looking for, that is the denser piece with a higher percentage of latewood, the dark rings.
I've been studying this picture since I was about 16. They did I think kind of bias the picture to make a point, and it does. Faster growth does not necessarily mean a stick is inferior to an older growth one. But neither is the opposite. That fast grown plantation fir has the highest density, in the pictured sample group. In framing you want denser lumber under the higher loads, kitchen, bath, workbench. For that its not about how many rings per inch the wood has, look for the overall highest percentage of strong dark latewood, fast or slow grown. If all things are equal, pick the heavier stick. All things are never equal when you're looking for the strongest stick, knots, slope of grain...overall where does each piece fall within the grade is all part of it, density is another one of the things you're looking at in the sort.
The other foot that then falls in all that, what shrinks, wood does. What shrinks more, denser wood, Dang!
If you're making a door panel where stability is the quality that means the most, lower density might be a better choice.
If they were trying to create a strong beam why isn't the strongest fiber on the bottom? They do that better now.
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MtnDon
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# Posted: 3 May 2025 09:09am
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DRP
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# Posted: 3 May 2025 06:43pm
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Thanks MD, I was hoping to jot down stuff as it comes to mind, hopefully some is of use to someone.
Mentioning density in relation to fastener strength... I'll attach a scan of one of the nail load tables from the NDS, National Design Specification for Wood Construction. We look to the building code where the engineer uses the NDS more. For instance the building code might specify 2 nails per bearing in a certain situation. If I step outside of the provisions of the code tables, an engineer having to figure it out from scratch is going to calculate the loads and then find the allowable load per fastener in the NDS and then design the connection that way.
The takeaway here is, while sorting through the stack, density holds fasteners better and gives higher load capacity. Notice in the table below the allowable load is directly related to wood density. If its a girder or ledger with a blue million joist hanger nails to go in it... pick the heavy hard one that's a bear to drive nails in, Dang!
There are pages of tables for different situations so as with many of those things, finding the correct table or equation to match the condition is critical.
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MtnDon
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# Posted: 3 May 2025 09:28pm
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Interesting table.
Do you know what the AWC connection calculator assumes about wood density?
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MtnDon
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# Posted: 3 May 2025 09:32pm - Edited by: MtnDon
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Ooops. Post duplicated
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DRP
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# Posted: 4 May 2025 09:08am - Edited by: DRP
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AWC/AFPA (American Wood Council/ American Forest and Paper Association) is the people who publish the NDS, the connections calc and the tables in the codebook. Basically they are the authority on structural wood. We can access their information at a basic level in the codebook, a much expanded level in the connections calc and the deep dive is in the NDS and associated papers.
I have not checked them but the connections calc should spit out very close to the same numbers as the tables in the NDS.
Open the connections calc here;
https://awc.org/calculators/connection-calculator/
Under Main and side member type click on that line and a drop down list of species will appear. You can change from the default Dougfir/Larch to any of the other species listed.
The calc and tables are using the average density of each species but as you can see they aren't listing density in the calc. As we make things easier to use it is easy to start losing the understanding behind what is going on.
Each species does have an average density but within the group there will be some sticks that are approaching "unusually light" (Weaker with less than normal latewood and lower nail holding ability) and others that approach "Dense" (Stronger, stiffer, better connection capacity).
The engineer uses the allowable strengths when doing design, everything in the pack "should" be up to that standard. A laborer builds with whatever stick lands in his hands and that "should" be good enough. A carpenter understands what he is looking at, understands what the engineer needs, and chooses placement more carefully when needed. Knowing that within a pack there are some pieces that are better suited to high loads and heavier connections a person can use pieces to their best advantage.
Thus far I've been showing a shear (lateral) loading table. Withdrawal is the other type of loading, pull out. First, don't load in withdrawal if there is any other way out of the problem, shear is more reliable. For example, people building with green lumber ignore several things. One of those is that a nail driven into green wood which then dries loses 75% of its withdrawal strength, so go carefully. Anyway, withdrawal is mostly about density, diameter and depth of penetration.
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DRP
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# Posted: 6 May 2025 11:39am - Edited by: DRP
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Cleaning up from the ice storm has had me up close and personal with our white pines the past few days. They are just beginning to put on the lighter, wider, lower density, earlywood portion of the annual growth ring. The trees are candling, over the next 30-60 days they will grow about 3' in height and 1/2" or so in diameter. The real growth spurt for most trees happens May-June. The rest of the year is spent on the latewood band, the narrower, denser, darker portion of an annual growth ring.
I mentioned our EWP's grow about 3' per year. The same species growing in NH or VT grows about half that amount per year. The rings are about twice as tight and the knots about half the distance apart.
We were building a big house with lots of porch ceiling. I had ordered what I thought was enough white pine T&G to do the whole job, and I was a little miffed when the local building supply delivered it and it had come from up north... wtf, we have a mill 20 miles away producing this stuff. Buy local whenever possible! I also had some transit damage that needed adjustment. Sure enough I ran a little short. Rather than order again I went to that local mill and bought the remainder. We began nailing it up and as we sat there eating lunch I looked at the new wood, and the yankee wood, and we took nown the new wood after lunch and called in an order for more northern pine. Same species but not a match  .
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DRP
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# Posted: 8 May 2025 09:09pm - Edited by: DRP
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A few posts ago I was talking about the rays in wood. One thing to think about is they also form a natural cleavage plane wherever a ray is. When I'm sawmilling any of the oaks when it is bright and very dry like this time of year, it is easy to start checks in the wood in a short time on direct sunlight, the checks begin at a ray on the surface.
Anyway, what brought that back to mind, I was in Hawkins Mechanical Dictionary from 1909 this morning, and this popped up;
Felt Grain: 1. The grain or split timber which is transverse to the annular rings.
2. The act of splitting timber by the felt grain.
I believe they were describing medullary rays 
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MtnDon
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# Posted: 9 May 2025 05:28pm - Edited by: MtnDon
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Quoting: DRP I mentioned our EWP's grow about 3' per year. The same species growing in NH or VT grows about half that amount per year.
Climate makes a real difference.
We had to take down a blue spruce here at home in the NM high desert (5500 foot plateau that gets a historical annual average precipitation of 8.2".) I didn't do it myself as there are a couple of low concrete block walls very close by, plus underground power lines with a distribution box within 2 feet. Not to mention the nearby house. So we contracted with an old-time, insured, local tree care company.
They used a bucket boom truck to dismantle the tree from the top down. They also did a good clean-up. $1100.
The blue spruce was about 35 feet tall and 15" in diameter, about 2 feet above ground. I counted 44 growth rings, which looks about right as we planted the short little thing in 1985 or 86. About 9-10 years ago we cut back on the irrigation as water is darn expensive when the wells supplying the water are 3500 to 6500 feet deep, and we have been in drought conditions for most of the last 10 years.
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cookie, 44 years
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DRP
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# Posted: 9 May 2025 08:47pm
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That's cool, I think I can see where you got stingy with water and maybe nutrients. Prior to that it looks like a strong tree, lots of good dark latewood and dense wood overall.
Its comparing apples to oranges... but as I sit here on the yoga ball having come home early and had too much fun, I'll try to recollect what I just cut.
I'm still opening up sunlight below the garden by taking out the unthinned eastern white pines. I dropped 3 and brought out 9 sawlogs from 2 of them. I think all told they were probably 70-80' tall and I was getting ~50' that would produce a 4x4 or better. I expect an 8x10 and an 8x8 out of 2 logs at the butt end (counting my chickens before they hatch!) They were a good bit taller than yours but diameter would be pretty close.
The third tree was a little stunted peckerpole. I failed to factor in its light weight gravity defying potential, it got hung up. I went over with the bobcat and pushed down on it with the forks. That worked and brought the worthless tree down, into the fence 
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gcrank1
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# Posted: 10 May 2025 08:45am
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Into every life a tree must fall.....
Where and how you dont want it
I had a ~60' bad jack pine blow-down hung up into the tops of a couple whites at our cabin . At least it wasnt into the cabin! It took me a year to think it through and feel like tackling it (Im NO lumberjack, more a jack of all trades, lol). When I did it went well and according to plan until the very end....... At that point it wasnt a disaster but I could've done better.
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DRP
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# Posted: 11 May 2025 07:09am - Edited by: DRP
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There's a chestnut oak up in the woods I've walked away from multiple times. Around the house I'll gladly pay to put them on the ground.
The first pic is of the haul from the past couple of days. Looks like a lot of 4x4's for something. The next pic is the top end of one of the larger logs, the sap is flowing. It makes it easy to identify the living sapwood!
3rd pic is of sapstain, or bluestain is another name. It is a sugar eating fungus so only affects the living sapwood cells where sugar is present. There are several standing dead trees in there hanging on. This was from one I knocked over.
4th pic, I mentioned hoping to get an 8x8 or 8x10 out of the larger logs. How do you figure that out? Use Pythagoras, A squared plus B squared equals C squared... so for an 8x8 I need at a bare minimum the square root of 128 inside of bark at the small end of the log. This one was about 12.5" and pulling out the handy dandy calculator it looks like I need 11.31" so if the log has little to no sweep it should work fine. (They are always straighter in the woods!)
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MtnDon
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# Posted: 11 May 2025 10:06pm
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40 years ago, we had just moved to NM. One of my first jobs was at one of the last sawmills in the area. They produced a lot of 1x4 & 1x6 T&G pine as well as large pine timbers. My job the first day was pulling the boards with the most bluestain as they came out of the T&G moulder. Those sold for a premium price compared to the boards with no bluestain.
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DRP
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# Posted: 12 May 2025 09:06am - Edited by: DRP
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I've seen it sold as denim pine. It is not one of the rotting fungi, it is a sugar eater. It is a sign that conditions are right for the rotters to move in if the wood doesn't get dryer faster. I've seen what its little root tips look like punching through cell walls and in furniture production we tried everything we could think of to remove it to no avail... so the appeal is gone for me 
We had one client that requested blue pine logs for his log home. They were only too happy to dump them on our job. The logs were air dried and the fungus was dormant when they arrived but before we got the roof on they got well rained on and "bloomed". Our client sanded the logs when it was dried in but did not wear a respirator. That was not a good move. A month or so ago we were prepping a bed to plant chestnuts for a trial. As my wife was blending the soil mix they specified I commented that she should be wearing a respirator and never looked to see that she did. Severe bronchitis, annie-B's and steroids later. I guess both would be farmers lung, do be careful around dust.
Fungi need for the wood to be above fiber saturation point, there needs to be free water available to feed them. That is the visible damp point as well, below that is bound water tied up within the chemistry of the cell wall, not really available to fungi. That point is in the mid 20-ish moisture content range for most species of wood which is the reason for the KD19 stamp on lumber, kiln dried, 19 percent moisture content, below the fungal zone.
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DRP
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# Posted: 17 May 2025 09:33pm
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I've had to run the job this week, which was fine, it rained all week. I went ahead and harvested what I could get out ahead of the rain in the garden pines. I have a pile of logs, a pile of "public" work and temps that will turn the logs blue sooner than later.
The first pic below is of some young, smooth bark on a pine branch. Notice where the protective skin is scraped you see bright green, chlorophyll. Under that young bark on many trees is the same thing. That is the winter leaf. Hardwoods drop their leaves to avoid desiccation and freezing in winter, pines have waxy coated needles and can survive to higher latitudes and altitudes, but all trees continue to carry on business through the winter. The myth about sap going down in winter is just that, cells do not survive embolism. If a water column is broken and airlocked from root to stoma or lenticel in the bark, that entire column dies. It is a capillary tube, when a molecule of water leaves the leaf it pulls everyone in the chain below it, all the way to the roots, up one notch, ready to repeat. Anyway, look at the bark on a cherry or birch, the horizontal lines are lenticels, the young bark's equivalent of a leaf's stoma, the lips the tree exhales through.
The second pic is of a couple of tulip poplar flowers, they are blooming now. It is not one of the true poplars but is in the magnolia family. With the demise of the chestnut it is the largest eastern tree.
oh, which comes back around to, how tall could that capillary water column be before the molecular bonds just can't hold it together? Some scientists did the math and came up with the answer then looked around, the height of a redwood .
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