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Lumber Sizes

Lumber Sizes

Lumber Sizes

(OP)
My local lumber store sells pine 2×4s that are 1-3/4" by 3-1/2". 2×4s are supposed to be 1-1/2" by 3-1/2", as are all the other 2×4s I have seen. I am designing and building bookshelves and chairs here, and this size has been a surprise. A pleasant surprise, but a surprise nevertheless.

Has anyone else noticed this? Am I dealing with a weird lumber store, or is there a different standard for knotty pine?

--
JHG

RE: Lumber Sizes

Yes that is normal

RE: Lumber Sizes

What grade of lumber are you looking at? What's stamped on the lumber? Weyerhauser / AFPA numbers and grades?
I've bought of oversize (or "on-size") lumber before, but found it in a separate pile from the general framing/construction 2x4's.

I could still build a wall panel with those 2x4's, that would fit in many cases, because the boards are just thicker, not wider than standard.
Improves by 36% column stability...

STF

RE: Lumber Sizes

(OP)
SparWeb,

2×4s used for studs around here usually are spruce. I don't recall seeing stamps on the wood I used on my backyard shed. These 2×4s are knotty pine, the cheapest material available for cabinet building. I am building a chair.

--
JHG

RE: Lumber Sizes

Generally rough sawn timber is to size less a saw kerf, planed & finished is always undersized because it starts off as rough sawn. Of course you can get 'specials' any way you like if you ask the mill, but you'll pay a bit of a premium.

RE: Lumber Sizes

Never seen a dressed (dimensioned) 2x4 which was thicker than 1.5". That's an odd lot.

RE: Lumber Sizes

Many years ago, lumber was cut to the actual size, eg; 2" by 4".
It was then planed down to 1 5/8 by 3 5/8. The old circular saws cut an 11/32 kerf. That's within a few % of 1/3 inch.
Lumber is now cut with much thinner kerf band saws. However, not all band saws are created equal. The thinner the kerf, the more tendancy to run off a true cut.
The last mill I worked in, the cut size was enough to ensure a good finish after drying, and planing plus an allowance for possible run-out in the cut.
Lumber shrinks as it dries and the amount of shrinkage depends on the grain orientation.
The normal steps are Cut green, kiln dry, and dress to finished size.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Lumber Sizes

Spruce 2 X 4's ? What I find is that 2X4's are made of popular.

I haven't seen pine 2X4's, just two kinds of pine of both flat or tung-and-grove.

Strangely so much of the wood seems to have a curve to it, that I don't think they are dried very much.

RE: Lumber Sizes

(OP)
waross,

On one of my early projects, I relied on the lumber tables of one of my college mechanics of materials textbooks, which quoted 1-5/8" by 3-5/8" for a 2×4. You know you are getting old when...

The stores in Toronto Canada have knotty pine, select pine, poplar, oak and maple. I can get cedar 2×4s and 4×4s. As I noted above, the structural stuff is spruce.

--
JHG

RE: Lumber Sizes

Around here if you want KD 2x4's you have to go to a real lumber yard, none of the big boxs carry them.
There is no spruce in the midwest, and doug fir only on a good day.
If you want #2KD (which used to be low grade) you have to hunt. If you need something better (SS) you probably have to order it.
The last 2x4s that I picked up were 1 5/8" x 3 1/2"

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Lumber Sizes

From what I've observed, since 2X4's are the standard for use as wall studs, that only the 3 1/2 dimension is held to any sort of consistent tolerance. The narrow dimension can very quite a bite. In fact, I suspect that what variance there is in the narrow dimension is perhaps an attempt to compensate for the strength and quality of the timber that it was cut from so as to maintain a certain minimum structural integrity. Note that this is just my humble opinion, but there is a hint of logic there.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

RE: Lumber Sizes

Local structural lumber in Toronto is 100% S-P-F - "spruce, pine fir"- a mixture of species. Never seen SPF 2x4s dressed to any dimensions other than 1.5" x 3.5". If they cut 'em a little thick, they'd typically plane more, as the sawdust is used in making MDF and other products.

RE: Lumber Sizes

(OP)
moltenmetal,

I am buying lumber from Lakeshore Lumber, in Etobicoke, near Lakeshore and Islington. The structural stuff with the rounded corners that I built my backyard shed out of, is 1.5"×3.5". They told me this material was spruce. When I order pine 2×4s, I get the size noted above, and the corners are sharp. This is not construction material.

--
JHG

RE: Lumber Sizes

The big box stores here have 2X4's in full if you want Ceder, and beetle kill pine in flat and Tung-and-grove. However I don't know why anyone would want beetle kill pile, as it has a gray color trough it.

The strange thing is they have the 2X3's in popular for construction grade. I guess this is for thinner walls.

RE: Lumber Sizes

Usually people have opted for thicker walls to gain additional insulation. My brother custom built his home in Northern Michigan using 2X6 wall studs so that he could effectively double the insulation thickness. He then wrapped the entire house with an additional 2 inches of foam insulation before putting on clapboard siding. All his windows are full wood casement windows with 3 panes of glass. He claims he can heat it for almost nothing in the winter and that it stays cool all summer as well.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

RE: Lumber Sizes

I have never purchased a standard framing 2x4 that was anything other than 1.5x3.5 in size... and I've gone through a LOT of wood over the years.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

BTW, I am NOT impressed with WeyerHauser's Framer Series lumber... it may be guaranteed straight, but there's so much bark on it it's difficult to ensure a nail gets enough bite. I won't be buying any more hacks of that crap again, especially at twice the price of a standard hack.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

OK, what you bought was actually 8/4 milled white pine x 3.5" wide- not really a "2x4" which implies structural lumber which is milled to consistent dimensions. Hardwood and softwood used for cabinetry can be bought dimensioned or rough and is sold by its nominal thickness in quarters of an inch, i.e. 4/4, 5/4, 6/4, 8/4. 8/4 material can sometimes clean up to 1 3/4" thick, sometimes 1 5/8", but you're guaranteed that it will clean up to 1.5" thick at thinnest when planed.

RE: Lumber Sizes

But a board listed as 8/4 should be 2" thick, not 1-3/4", as it's meant to be cabinetry stock... 1-3/4" is a 7/8 board and would be listed as such. If it's listed as a 2x4 in a BORG, 1.5" is the correct thickness.

Leave it to woodworkers and the industry to screw it up, same as providing size "classes" for monitors (and now TVs). I remember back in the day getting a 17"-class monitor and being shorted too many millimeters for my taste. It's either 17" or it's not.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

Over here a 'metric' rough-sawn 4x2 is generally about 98mm x 47mm, which is about 4mm down on nominal. Most of what I see seems to be cut by circular saw, not a bandsaw, judging by the marks.

We also get 'CLS' - Canadian Lumber Standard - which is planed and has beveled corners. Joiners like it because they don't get splinters in their hands so often. A CLS 4x2 is about 89mm x 38mm or ½" down on nominal size in each dimension.

Seems like you guys get a poor deal - under-sized lumber, 3/4-gallon gallons, no proper beer... winky smile

RE: Lumber Sizes

Lots and lots of proper beer, but only from smaller breweries. None of the mass market horse pee qualifies. Go for the ales and be wary of the lagers.

RE: Lumber Sizes

Quote (MacGyverS2000)


Rereading my last comment, that should have read "1-3/4" is a 7/4 board"... sorry about that.

You know don't you that you can now go back and edit your own posts, at least for a day or so. Just look in the lower right corner of any of your recent posts and you should see an 'Edit' icon, as shown below;



Just keep in mind that after a post has been edited anyone can take a look and see what it was that was edited so you can't use this feature to 'rewrite history' or completely 'un-ring' a bell winky smile

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

RE: Lumber Sizes

(OP)
ScottyUK,

Before Canada turned metric, we used Imperial gallons. I remember the signs on the gas pumps announcing to Americans that our gallons are bigger.

It does seem some of my local 2×4s are bigger. I was planning to publish the drawings of the chair I am building. Things are inconvenient when it turns out I am using some sort of exotic material.

--
JHG

RE: Lumber Sizes

The 'edit' feature has been there for several months now.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

RE: Lumber Sizes

And very welcome it is. smile

RE: Lumber Sizes

An 8/4 hardwood board is, in fact, 1-3/4 inch thick. Actual will always be 3/16 to 1/4 less than nominal. Coniferous varieties have up to 1/2 allowance below nominal.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Lumber Sizes

I would be quite upset if I paid good money at the local sawyer for an 8/4 board and got a 7/4 in return... but I bet a truckload of 1/4 boards could be carried by a single person!

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

So, am I the only one that is looking to use steel studs for framing? They're straight, holes bored for electrical and plumbing. I've got a small shop (residential - 24x32 maybe) build coming up, hopefully next year, I'll be pricing material and labor for both wood and steel. I'll be surprised if wood studs comes out cheaper.

Harmless flakes working together can unleash an avalanche of destruction

RE: Lumber Sizes

Sure, but they don't bear load. If nobody says so in the OP, I assume the wall is load-bearing and hence needs the strength and stiffness of the wood studs. For filler-walls under the span, hey, steel studs are great.
Who's framing walls?

STF

RE: Lumber Sizes

OP;
"I am designing and building bookshelves and chairs here,"

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Lumber Sizes

<tangent>
At a former shop, we had one of the bathrooms completely replaced.
The new interior structure plans called for steel framing.
The guy who erected the framing spent two or three whole days on what he had bid as a one day job, because his supplier had done him a favor by selling him 16 gage framing instead of the normal, what, 26 gage tin.
He couldn't find a self-drilling screw that would go through the framing; he had to predrill every damn fastener. Boy, was he pissed.
</tangent>

Mike Halloran
Pembroke Pines, FL, USA

RE: Lumber Sizes

I tried steel for the wall behind my wood stove. I did not notice until after it was in place that the holes did not match up.

Needless to say, they do have a top and bottom, but is un marked as such.

RE: Lumber Sizes

Steel framed walls take some experience to put up correctly.
Some brands have the logo printed on one end so that you can keep them straight.
With plywood sheathing you can build very strong walls.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Lumber Sizes

I used cement board to keep it fire resistant. But it was difficult to attach.

Steel studs seem weak at first, but when I put them back to back they were more ridged. Maybe not necessary, but it made me feel better about them.

Also mixing different brands is not a good idea either, as you can be sure the holes won't match.

RE: Lumber Sizes

I'll be putting up a lot of cabinets in the shop, wine holders on the walls of the wet bar, and TV/stereo equipment on the walls on the entertainment room... I want wood studs thumbsup2

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

8/4 lumber is rough sawn to 2" nominal thickness. It will plane smooth both sides to anywhere between 1 7/8 and 1 1/2 thick depending on how good the sawyer was, the width of the plank, and on the type of saw used (the old circular sawmills being the worst, behind a bandsaw mill with a dull blade). The /4 dimensioning is for rough lumber only- there is no guarantee of finished dimension.

Softwood lumber used for framing is milked to consistent dimensions. Studs and fence boards tend to be cut to precise lengths. Longer boards tend to give you a kerf allowance, ie a 16' board may be 16' 0-1/4" long so you can cut it into a few pieces without being short by your saw kerf width.

If you joint rough cut lumber, ie if you also care that the piece ends up straight as well as having parallel smooth faces, it will end up whatever thickness it takes to get it straight. For a long enough piece, that may be impossible. Sometimes, you need to design the structure of what you're building to hold the material straight rather than designing for straight material.

Furniture is best made from rough lumber, which can be cut to rough dimension and then jointed, thickness planed and dimensioned with minimal waste.

You bought material that was rough cut to 8/4 and then thickness planed to 1 3/4". Nobody cheated you, nor did you get something for nothing.

RE: Lumber Sizes

Quote (moltenmetal)

... Furniture is best made from rough lumber, which can be cut to rough dimension and then jointed, thickness planed and dimensioned with minimal waste. ...
I sure you are correct that is the minimal waste method.

Not having a cabinet shop, but still having pretty nice tools - for a DIY, but no planer, no shaper: I tend to buy S3S 3/4 X for 99% of everything I do. If I need a special thickness, our local hardwood supplier will run it through his planer for me - for a suprising nominal fee. Have not had any use (yet) for rough cut hardwood - and the intesnsive labor required.

Just the opinion of a DIY engineer - not a professional cabinet maker like his dad was.

ice

Harmless flakes working together can unleash an avalanche of destruction

RE: Lumber Sizes

I didn't have a jointer to a thickness planer for years, and it's surprising what you can accomplish without them. Milled hardwood is pricey here.

Eventually I bought both so I could work with rough lumber efficiently without spending my life hand planing, which loses its charm rapidly if you want to build more than a few small pieces. Some material I found and sawed myself, including a pile of short 8/4 cherry I've been using for legs and cabinet corners over the years. I now have a huge pile of green ash air drying in a stickered pile in my backyard- thanks to the emerald ash borer, an understanding neighbour who had the arborist fell his dead trees rather than hacking them into firewood, and a great young guy with a portable bandsaw mill. Building my kitchen (all doors, drawer fronts and face frames) from rough cherry paid for these tools several times over.

RE: Lumber Sizes

Sounds to me like an odd supplier. Changing from 1.5 to 1.75 would hurt the yield from a log, and if you have ever been in a sawmill, that is important to them.

S4S or S3S is handy for those without the equipment, but most of the time it is not all that useful for a furniture building unless it is the correct size. Many times sawing relives tension stresses within the wood, and you will find it ends up crooked once cut. It takes a jointer and planer to fix. I buy 8/4 6/4 and 4/4 from a wholesaler at about 1/2 the price I can buy it from a local shop in dressed form. If you do much woodworking a cheap 6" jointer and lunchbox planer can be a savings if you have the patience. Norm Abrahams (this old house or whatever it was called) built a shed on his show one time, and the crazy bugger jointed and planed all the pieces. Way too dedicated I thought.

Here is some of my floors and my stairs before it got to the shop.

RE: Lumber Sizes

Jointing and planing lumber used for framing carpentry is smashing a fly with a sledgehammer- unless it's rough lumber and it's sawn badly.

RE: Lumber Sizes

Being able to buy cull lumber at a reduced price, has motivated me to undertake many projects that I would not have had I paid the full price.
So those crooked pieces are not all bad. However Home-Depo seems to have many more than what people want (Not that I blame Home-Depo).

What it appears to me is that much of the lumber is not allowed to dry prior to being cut. And it's so bad that I can frequently find lumber wet in the store.

The other thing I've seen is 2 X 4's that have bark on one end. And while not crooked, they are frequently rejected to the cull bin.

I am guessing all of this happens because of the rush to profits from saw mills, and trying squeeze as much wood from every tree. It's not just limited to the lumber industry, but maybe we just see it more.

RE: Lumber Sizes

They're crooked (cupped, canted, etc.) because they're often cut entirely too close to the pith (I'd say 20%+ actually have the pith still in them). You can get pretty close to quarter-sawn with the entire log if it's cut correctly... but the cut down trees to early, which means the logs are too thin to really adjust the cut properly. Sad, really.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

The volume mills in Western Canada that cut construction grade lumber these steps.
1 The lumber is rough cut.
2 The lumber is dried, usually kiln dried.
3 The lumber is planed to the finished size.
Lumber is often shipped by weight. Kiln drying saves a lot in shipping costs.
Lumber shrinks when dried. Lumber does not shrint uniformly.

The worst case that I have seen was a kiln load of tropical flooring in Central America. The operators were instructed to first dry the wood and to then plane it to size. This was a wood that was very hard when dry. The operators decided that it would be too hard on their equipment to plane the wood when it was dry and planed the wood green.
Remember, this was flooring, one uniform spec size.
All the boards shrank and would not match up with standard flooring.
That's not all;
The edge grain shrank by a different amount than the flat grain.
The flat grain shrank by a different amount than the quarter grain.
They ended up with three distinct different widths and three difference distinct thicknesses, depending on the grain orientation.
$40,000 potential value of wood at distress sale prices.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Lumber Sizes

Sorry, Bill, I should have been more detailed in my response. Wood will dry (relatively) uniformly if the grain is uniform. By cutting as close to quarter-sawn as possible, the piece will not warp to any significant degree. This can then be planed with a minimal loss of material. The path you mention serves the same purpose, just from a different direction...

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

Trees grown to large diameters in tall dense forest can have beautifully straight grain and can be handled as described- the entire lot quartersawn, or better still, rift sawn (i.e. every board taken centred through the diameter of the log) and dried, leaving you with nice (nearly) straight boards.

That describes approximately zero of the wood I've used in the past twenty years or more.

Rift sawing wastes a huge amount of wood. Quartersawing wastes less, but yields a lot of narrow boards unless the log is huge. Both methods consume a lot of saw time, which on a portable sawmill can add up quickly. In some species, these methods give a look which is very different- almost like a different species. Sometimes that's charming in its own right (i.e. the ray flecking in quartersawn oak), giving features that are valuable as well as imparting dimensional stability. But in some species, it makes a beautiful wood look rather plain by getting rid of the very grain varability that draws your eye to it in the first place- it feels less like a natural material.

Flatsawn material builds up stresses when dried, even when air dried very slowly in a stickered pile. It takes on whatever new shape those stresses decide. Sawing it relieves some stresses and changes the shape again. After it is dried, you look at the boards, lay out the pieces you need, and start bucking and ripping to rough dimension. Then you can dimension the lumber with minimal waste. But it takes time and patience and generates a lot of shavings.

RE: Lumber Sizes

A note on drying:
Soft wood has an open cell structure and can be dried rapidly.
Hard wood has a closed cell structure and must be dried slowly.
What is "rapidly" and "slowly" in hours?
I have used drying schedules that would dry a batch of soft wood in 18 hours.
My drying handbook listed some drying schedules for hardwood that ran over 28 days.
If you dry the wood faster than the moisture can migrate to the surface, the vapour pressure may split the wood.
I have seen peak spot temperatures in a softwood kiln hit 230 deg. F

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Lumber Sizes

Pacific Northwest Pine. Some areas only. The same species from a different area may take 24 to 36 hours to dry without damage.
That was a long time ago when CRT (Constant Rising Temperature) schedules were used to dry soft wood.
The hotter softwood is, the more permeable the cell structure is. The more permeable the cell structure the faster the wood may be dried without the internal vapour pressure splittng the wood.
It was found that the wood could be brought up to temperature faster by flooding the kiln with saturated steam. It may seem counter productive to inject steam and make the atmosphere wetter when you want to dry the wood, but the steam and external moisture allowed the wood to be heated up more rapidly without damage. Once the wood was hot, it could be dried very rapidly with an overall reduction in drying time.
Counter=intuitive but it works.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Lumber Sizes

Quote (waross)

It was found that the wood could be brought up to temperature faster by flooding the kiln with saturated steam. It may seem counter productive to inject steam and make the atmosphere wetter when you want to dry the wood, but the steam and external moisture allowed the wood to be heated up more rapidly without damage. Once the wood was hot, it could be dried very rapidly with an overall reduction in drying time.
Counter=intuitive but it works.
Yes, and no. In the turning world, one method often used to dry thick blanks (without splitting) is boiling the piece. A few hours in the dunk and the piece will usually dry without splitting in a few weeks. When you're trying to quickly dry a 12" thick bowl blank, everything becomes an option. Works with most woods.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Lumber Sizes

The steam keeps the surface of the wood wet while the heat force the moisture out from the center. Steam is reduced as the core dries so that the wood dries from the inside out. Without the steam it would dry from the outside in and have to be dried much slower.

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