Are softwoods really more stable than hardwoods?

[Bombarde16]

People say it on the internet so it must be true, right? 

The rumor is that softwoods (spruces, pines, firs, etc.) are, once dried, actually more stable than hardwoods. It's counter-intuitive, since most of us encounter softwoods as construction lumber which is carelessly milled and sold sopping wet. But, the rumor goes, if you treat a piece of SPF with the attention and love that woodworking entails (i.e. rip out the pith, stack it, let it dry, mill it square, etc.) it will reward you with greater stability through the seasons than its deciduous brethren.

Myth or Truth? My instinct is that it's technically true...but that the supposed benefit is generally not enough to outweigh the extra hassle of salvaging usable stock from construction lumber, especially among a.) professionals for whom time is money and b.) beginners who may not fully understand the subtleties of drying and milling lumber. The exception to this would be the less common case of an advanced hobbyist who a.) isn't counting his hours as money and b.) who understands how to mill lumber and possibly c.) who has access to "free" scraps from a construction site or a dumpster.

Thoughts? Does anyone have any practical experience with this?

[drzaius]

6 minutes ago, Bombarde16 said:

The rumor is that softwoods (spruces, pines, firs, etc.) are, once dried, actually more stable than hardwoods

I've not noticed that, but my experience is far from scientific. I do believe that other factors are far more important to wood stability, such as old growth vs fast grown farmed lumber and the absence of pith.

[Chestnut]

The factor that causes movement is the difference in expansion or shrinkage between the radial direction inside the board and the tangential. Radial is the change in diameter of the log and tangential is the change along the growth rings. This is often expressed as a ratio. The closer to 1 of the ratio the more stable the wood is going to be. Also the lower the percentage of shrinkage in either direction the more stable the wood will be and the less it will change size. If the ratio is 1 and the percentage is 15% it'll move a lot but would in theory be stable. Wood is natural and theory goes out the window so don't count on that.

Some common hardwoods are screen shot below from wood database. Cherry and Oak are on the more unstable size with TRs of 1.9 & 2.2 Walnut is quite stable as is Mahogany. Despite walnut having a low TR it's higher shrinkage tend to give it a worse reputation as far as stability is concerned when compared to Mahogany. Mahogany is well known for being a very stable wood.

Below are the SPF softwoods with WRC included for comparison.

In conclusion it's not clearly cut and dry this is also a small sample but on average softwoods have lower shrinkage numbers and better TR ratios. Like everything that depends on the species and most importantly how the log is sawn.

From my under standing spruce is more common in smaller boards like 2x4s and it's specs reflect the reality that those boards move a lot more. Fir is more stable and has better properties all around which is why it's more common in larger lumber. This is all regional dependent. SE everything is likely to be SYP west coast is likely to be fir.

This is all information learned from listening/reading Shannon Rodgers. Lumber Industry Update has a lot of good information on all things wood though it's from a single person with their bias in it so i can't say that i have multiple sources and multiple perspectives.

I shouldn't have included Mahogany, that wood is very well known for it's superior stability.

 

[BillyJack]

I've cut pine and twist coming out of the saw like a pretzel, yet I've had maple do the same thing...some woods are  just squirrely no matter what....buy your furniture and you'll never encounter this again..hehe

[curlyoak]

I think it has more to do with which tree. I have seen some beautiful sitka spruce. Clear and straight grain. The center of all logs has dramatically different grain tensions than the rest of the log. And very unstable. And hardwood also varies. Generally speaking, the higher the grade the more stable. But each species may have slightly different standards for grading. Honduras mahogany was the main choice of pattern makers of days gone by. They would shape material for sand casting auto parts. The honduras mahogany is all gone along with the pattern makers...

[Chestnut]

6 minutes ago, curlyoak said:

I think it has more to do with which tree. I have seen some beautiful sitka spruce. Clear and straight grain. The center of all logs has dramatically different grain tensions than the rest of the log. And very unstable. And hardwood also varies. Generally speaking, the higher the grade the more stable. But each species may have slightly different standards for grading. Honduras mahogany was the main choice of pattern makers of days gone by. They would shape material for sand casting auto parts. The honduras mahogany is all gone along with the pattern makers...

I can buy Honduran Mahogany quite a few places. I have a stack of it. Are you thinking Cuban Mahogany?

[curlyoak]

I know there is some to be bought. I imagine it is costly. I remember when it was cheap. What do you pay? And where do you get it?

 

[Chestnut]

$8-$9/ BF hardwood shop in Minneapolis and a cabinet shop in the middle of no where ND. People had always raved about how awesome and beautiful it was. The experience left me lacking and wishing I'd spent my money on walnut.

[curlyoak]

All mahogany these days from the Latin America area is known as genuine mahogany and sold as honduras. Good wood but not Honduras. Sapele has become my choice.

[Chet]

16 minutes ago, Chestnut said:

People had always raved about how awesome and beautiful it was.

In the future, when ever that may be, think Sapele instead.  When I was in the lumber yard purchasing the Sapele for the chair it was a couple of bins down from the mahogany and I couldn't believe how much nicer the Sapele looked.

12 minutes ago, curlyoak said:

Sapele has become my choice.

Yep.

[curlyoak]

The best was Honduras. I remember in the 70's incredible lumber. Flat, stable, ribboned grained quartered, clear and beautiful. Not unusual for 24" wide boards. Bound to be some of that still around. Too expensive for me. I'll get Sapele.

[Chestnut]

2 hours ago, curlyoak said:

All mahogany these days from the Latin America area is known as genuine mahogany and sold as honduras. Good wood but not Honduras. Sapele has become my choice.

You do realize that Honduras is in Latin America and is where the Honduran Mahogany gets it's name from right?

Swietenia mahagoni Is the tree that was harvested in Cuba that was harvested and imported until the 1940s. It was typically harvested along side Swietenia macrophylla unknown to those doing the harvesting. Anything offered as Mahogany after 1946 was Swietenia macrophylla or Honduran Mahogany. The stock I had to pick from was 9-12' long, 12-18" wide and 6/4 - 12/4, completely clear. It was just boring it had little grain and little character. I've seen Sapele and it wasn't nearly as nice as the "genuine Mahognay" aka Honduran Mahogany.

Buying quartered stock or flat sawn stock is just different sawing methods Genuine Mahogany wasn't typically quarter sawn. Sapele is a VERY different breed. It presents far more figure and it's interlocked grain produces very strong ribbon strip effect that isn't as strongly present in Cuban or Honduran Mahogany. My hands on experience is limited but after seeing the stock in person I did a lot of research Sources below.

https://www.wood-database.com/wood-articles/mahogany-mixups-the-lowdown/

https://www.mcilvain.com/hardwoods/genuine-mahogany/

http://hobbithouseinc.com/personal/woodpics/_discussion_mahogany.htm

The underlined I will admit is conjecture on my part based off of my experience of touring historic houses.

[BillyJack]

4 hours ago, Chet said:

In the future, when ever that may be, think Sapele instead.  When I was in the lumber yard purchasing the Sapele for the chair it was a couple of bins down from the mahogany and I couldn't believe how much nicer the Sapele looked.

Yep.

I got a lot of Sapele. Nice wood if I could just decide what to build with it..gonna save it for Arondock  chairs but im.a bit shy to cut so much up as there 16' long...

I'm not much for mahagony....

[curlyoak]

8 hours ago, Chestnut said:

You do realize that Honduras is in Latin America and is where the Honduran Mahogany gets it's name from right?

I have traveled the area multiple times!  Like quartered oak has fleck, Quartered mahogany is ribbon grained. And when honduras mahogany was in its heyday it was mostly quartered. That demand started because of the pattern makers preference. Tons of Honduras went to Detroit and surrounding area. All of the sand castings were exclusively Honduras.

You do realize I am an antique and I have hands on experience of being there? Not just book reference or conjecture?  

[Ronn W]

On 12/27/2019 at 12:53 PM, Chestnut said:

$8-$9/ BF hardwood shop in Minneapolis and a cabinet shop in the middle of no where ND. People had always raved about how awesome and beautiful it was. The experience left me lacking and wishing I'd spent my money on walnut.

Where do you get it, Drew?  I have not yet d one a nice piece out of real Mahogany, but would like to.

[Chestnut]

Youngblood before it closed had some. The stuff I bought came from ND. The cabinet guy there had 1k-2k BF.

[BillyJack]

I have several sheets of Sapele ribbon striped veneer and sheet goods .to bad it will probably be y become shop.fixtures or painted shelves f in r the grand daughters room...the lumber I will probably use for chairs....

[Chip Sawdust]

I love the look of sapele and mostly enjoy working with it. Finishing it to a smooth, flat surface is a little problematic as it’s a bit open grained. But with enough elbow grease it looks fantastic. This piece I used that Aqua Coat stuff and it turned out nice. Here it still needs another coat...
 

 

And like “mahogany” it goes really well with maple