I was at Owl Hardwoods a while back and they had a few pieces of hardwood which easily measured 30+ inches wide, about 1-1/4″ thick and maybe 8′ long. I don’t know what species it is (actually, they had a few of different species), but the grain was fairly straight and tight. I’m sure it was throroughly dry, all the boards are finish planed on two sides. My question, if I used one of these boards as a desktop or counter top, what are the chances that it will eventually crack?
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Cracking isn't all that likely if the end grain is well sealed with the finish and the top is mounted to the base with some way to let it expand and contract about an inch. What you would have to worry about is warping which could be considerable depending on how the grain runs and the species. It almost certainly won't stay completely flat in any place where the humidity varies a lot over the year.
John White
I don't know about the wood now a days. But one of my last trips to Ireland for work included a couple castle tours. In several of them the main dining tables were huge solid tops. 300 to 400 years old! Probably 30" wide, 4 or 5" thick and 20' long or so. 1 Piece. Other than dishing in the wood where it was abviously used for a very long time. No big check or cracks in the tops. Seriously stout tables. Now how they got them in there in the first place I am still trying to figure out. Would have to be from window as stairs are tight spiral staircases in the corners.
But they obviously did something correct in building them and sealing them.
No central heat in an environment that is relatively stable for humidity year round would explain their stability.John White
Actually there was "central" heat. Litterally a fire in the middle of the floor in the middle of the room. Hole in the roof of the cathedral ceiling and just let it rise up and out. But it was nothing like we have for central heat today. ;-)
If I ever run into a piece that big it's gonna become a table, end splitting or not! =] I can just imagine the tree it was cut from.
But so, basically I'd be safe as long as I do some sort of slots for movement when fastening it to a base. The piece I'm thinking about using will rum me about $350, so I'm not sure how soon I'll be able to do it, but I plan to sometime maybe this spring. Thanks for the feedback! :)--------------------------------------------------------
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If it does crack or check. Just consider it character.
Ted,
I've made quite a few pieces of furniture using full width boards, with no problems at all. Admittedly most of these were in mahogany, a stable wood. I did use some 17" wide curly maple with no problems either.
I once found a very nicely figured piece of mahogany at the bottom of a stack. After digging it out, it had a cup of about 3/8" over its 27" width, but it was still thick enough to plane flat and make a sideboard top, so that is what I did. The man behind the counter said, it would warp and crack. That was 9 years ago, and despite the piece being near a forced air register duct, the last time I saw it remained perfectly flat and check free.
I think that if the board went through the process, from soaking wet tree, to less than 10% moisture content and remained flat and crack free or nearly so, it is highly unlikely to radically change shape in the comparatively minor moisture changes in a modern home.
Stability comes from proper drying, stock selection and joinery ( making allowances for movement) not from the width of the individual boards in a panel. I have never bought into the, glue ups are more stable theory, and don't get me started on the alternating growth rings fallacy.
Rob Millard
http://www.americanfederalperiod.com
Rob,
I took a look at your website and I gotta say, you obviously know your wood. Thanks for the feedback. :)--------------------------------------------------------
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Mahogany is exceptionally "friendly" in that its tangential and radial shrinkage rates are pretty close. Black walnut is similar.
-Steve
Rob,
Amen, and amen. If a board remains flat going from saturation to dry, it will remain so from season to season. Allowance for movement in width is important, of course. And boards from either near the heart (containing juvenile wood, and a significant part of growth rings), or from the periphery of the log, with mostly sapwood on one side of the board, and heartwood on the other, are likely to be unstable.
I believe the practice of ripping wide boards into narrow strips and gluing them back into wide panels is a production-oriented means of minimising the effects of using random stock that might have boxed heart, or sap faces, without having to take time to teach a line worker to hand-select around these problematic pieces.
Ray
Ray, aside from you no-one has referred to the end grain configuration here. I have some large wide paduak in my loft, quartersawn, and it has not moved in twenty years (a bit like me). Splits I reckon I can live with but cupping can be a nightmare.
mufti,
Early on, I was taught the simple rule of thumb, that "growth rings want to straighten out", when a board is drying; a simplistic way of explaining the differential between tangential and radial shrinkage.
I've seen several references , on various threads, to sawing a plank from the center of the log. Capturing the pith (center) of the log, "boxing the heart", is always going to cause severe splitting, cupping or both. Might as well saw down the center of the plank and be done, for the middle of that plank is trash anyhow.
Your description of the quartersawn plank's stability is what one would expect. The segments of the growth rings are short, with nearly all the movement in the radial direction. Conversely, a flatsawn, (slabsawn) plank has the best chance of remaining flat when it is from near the outside of a large log, so that the growth rings are relatively large diameter, and thus run relatively straight across the end of the plank. Such wide pieces are scarce, and many wider planks are cut from nearer the center, where, approaching the heart, the diameter of the rings is smaller, and more of the "circle" is captured within the board (near its middle). These guys will exhibit more of a tendency to cup, as the tangential shrinkage component approaches more of a semicircle "trying to straighten out". Add to that the likelihood that planks taken near the heart will have more defects, from small limbs growing from the juvenile tree trunk that are "self pruned" as the tree matures and grows taller, and these knots are grown over by later wood. Makes for more instability from stresses induced by drying.
Ray
It depends on a lot of variables such as species, grain (quarter sawn, plain sawn), climate, sealing of the wood etc. Planks that big are most likely quarter sawn simply because to get that kind of width one would have most likely cut the planks from the middle cross section of the log.
I expect to be going by Owl Hardwoods some time this week and I'll try to get some photos of the pieces I'm asking about, along with some shots of the end grain, and find out what species they are.--------------------------------------------------------
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