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[quote="JPG40504"]An 'excellent' example of why it(board ft) confuses so many! Their 'technical advisor' is a rambling idiot. That is why explaining by 'example' is usually doomed to failure.

Cubic inches it totally irrelevant. What it measures at the lumber yard after planing is irrelevant. Only thing that counts is the size it was rough cut from the log and the final length.

Yes hardwoods are handled differently and somewhat looser(caused by randomness of sizes). Not sure I unnerstand all I read about that today!]
Buying hardwood is definately confusing at times....even at my favorite Amarillo Hardwoods. When I bought the soft maple for the bookcase project, I asked for 4/4 soft maple. The guy says "Sure, you want that in 7/8 or 13/16?".

Now we have the 3/4" plywood is not really 3/4" any more.....

Can remember when I was a kid, a "one-by" measured 7/8" and the old-time carpenters struggling with remodels to match up the new-fangled 3/4" lumber

Gene Wengert knows wood and is well respected on the subject. Some years back I was thinking of building a solar kiln for drying lumber and that's when I ran across info on Wengert. He had plans for one and if you do a google search you'll find plenty of info on him and his work.

Here's some of that info:

Gene Wengert is President of The Wood Doctor's Rx, LLC, 2872 Charleston Drive, Madison, WI 53711-6502 and Professor Emeritus at the University of Wisconsin-Madison.

As a former professor and extension specialist at Virginia Tech and researcher at the US Forest Products Lab, Gene teaches over 30 practical wood processing classes and seminars a year for the wood products industry, including sawing, edging, grading, drying, machining and gluing.

Gene is the author of eight practical books and has published over 400 articles relating to the wood products industry.

With that background, I'd expect he knows what constitutes a board foot of lumber, but I'd also expect that he's thinking along legal and lumber industry lines. For the guy going down to the lumber yard to buy six boards for making a bookcase, you're likely to find that a board foot of rough lumber is 1' wide by 1' long by 1" thick or 144 cubic inches. That 144 cubic inches likely a gross figure that includes some loss for shrinkage in both thickness and width. And, for surfaced lumber, you lose 3/16" to 1/4" in thickness because of the planing. And, some sellers measure differently or round differently than the next guy, so that's another variable to consider.

You can always ask the guy selling the lumber how he arrives as the measurements.

JPG40504 wrote:Rough cut lumber is smaller than 2x4 by the saw kerf.

Sorry to tell ya, but the last rough cut lumber I bought measured 4/4 and 8/4. 4/4 = one inch and the 8/4 measured two inches. I bought it from an urban logger.

pennview wrote:Gene Wengert knows wood and is well respected on the subject. Some years back I was thinking of building a solar kiln for drying lumber and that's when I ran across info on Wengert. He had plans for one and if you do a google search you'll find plenty of info on him and his work.

Here's some of that info:

Gene Wengert is President of The Wood Doctor's Rx, LLC, 2872 Charleston Drive, Madison, WI 53711-6502 and Professor Emeritus at the University of Wisconsin-Madison.

As a former professor and extension specialist at Virginia Tech and researcher at the US Forest Products Lab, Gene teaches over 30 practical wood processing classes and seminars a year for the wood products industry, including sawing, edging, grading, drying, machining and gluing.

Gene is the author of eight practical books and has published over 400 articles relating to the wood products industry.

With that background, I'd expect he knows what constitutes a board foot of lumber, but I'd also expect that he's thinking along legal and lumber industry lines. For the guy going down to the lumber yard to buy six boards for making a bookcase, you're likely to find that a board foot of rough lumber is 1' wide by 1' long by 1" thick or 144 cubic inches. That 144 cubic inches likely a gross figure that includes some loss for shrinkage in both thickness and width. And, for surfaced lumber, you lose 3/16" to 1/4" in thickness because of the planing. And, some sellers measure differently or round differently than the next guy, so that's another variable to consider.

You can always ask the guy selling the lumber how he arrives as the measurements.

I did not mean to question his knowledge nor credentials. There was no doubt in my mind he knew of what spoke. Yes idiot was too harsh, but to the point.

Trouble is no one who was seeking clear concise definitions was so informed by the 'examples' and tangents he went off on. A square foot is 144 in² and if 1" thick would be 144 in³ but to the poor guy trying to understand what is on the lumber yard racks that merely adds a point of confusion since the relevant in³ was only in existence back in the forest!

If he was associated with FPL, that explains a lot. (I spent too much time too close to Madison in the past).

Proof of what I say is the fact that even Dusty became cornfused reading his 'explanations'.

Hard to explain something that one cannot touch or see etc.

[quote="JPG40504"]I did not mean to question his knowledge nor credentials. There was no doubt in my mind he knew of what spoke. Yes idiot was too harsh, but to the point.

Trouble is no one who was seeking clear concise definitions was so informed by the 'examples' and tangents he went off on. A square foot is 144 in&#178]
I don't think my confused state makes your point, JPG. Remember, I was confused when I started the tangent to this thread.

I bought commercial plans for some band saw boxes. All the plans call for laminating 4 ea. 5/4 pieces to get a block that measures 16"X8"X5 1/2".
So Dusty, you ain't the only one that's confused!

dusty wrote:I don't think my confused state makes your point, JPG. Remember, I was confused when I started the tangent to this thread.

Of course not!:D:D:D:D

Methinks you became more so after reading it though.

It frustrated me in that the 'explanations' were muddying up the issue and not addressing the basic question. Yes the issue is quite muddy without adding to it.

But I dare say not very many folks gained a better understanding from that!


What I learned from this today is that I need to be prepared to ascertain exactly what is offered prior to agreeing to purchase anything other than dimensioned construction grade lumber!

Gene Howe wrote:I bought commercial plans for some band saw boxes. All the plans call for laminating 4 ea. 5/4 pieces to get a block that measures 16"X8"X5 1/2".
So Dusty, you ain't the only one that's confused!

AIUI 5/4 can be as thick as 1 3/8(and more) so where's the problem?:D

Right, when pig's fly!

Here is a source of information that I can understand and don't get terribly confused by. At least I don't think I do. The comments from poster "K" was particularly informative. I hope it is accurate.

If you are interested in this sort of information AND are having trouble sleeping, click here and start reading. This should help, one way or:) another.

NOTE: Hardwoods and Softwoods are different. They are milled differently, graded differently and priced differently. When you grasp onto a "fact" make sure it applies to the type of wood that you are thinking/talking about. The "fact" may not apply to your specific piece of wood.

If anyone needs additional confusion on lumber, take a look at Wood Magazine's cut list for a project.

What I just noticed in the last magazine was a cutting diagram that showed several parts cut from a piece of planed wood 1/2 x 5 1/2 x 72" and describing that as 1.5 board feet of oak. But, if you were buying that wood in the rough, you'd need about 3 board feet because you'd have to surface plane it. You'd typically have to start with 4/4 lumber and then plane it to the 1/2" finished size. Moreover, the parts are laid out on boards that are the size of softwood boards width wise, e.g., 5 1/2" and 7 1/4". On the other hand, I've never measured the size of wood sold in a place like Home Depot, but perhaps that is how they sell it.