Replies

1. 
   kennedy136 | Mar 28, 2003 05:23am | #1

   Bob,

           Once dried walnut is very stable, about the same as mahogany and better than cherry.  It is a joy to work with, moderate hardness, carves well, takes a great polish when handplaned, not to mention being very attractive.  My favorite wood.

                                                          Mark

2. 
   Clay | Mar 28, 2003 06:06am | #2

   I disagree with the professor.  Nothing else is really as stable as mahogany.  Walnut is a decent wood to work with though it often has some knots and or other grain configurations that can release tension when the planks are cut causing movement.  It also seems to be prone to movement when planed or ripped suggesting that it may often case harden a bit when being dried.  Despite these things it is a pretty good wood to work with for most types of projects.  Do you have kiln dried stock?  Because if you don't then you may be using stock with too high  a moisture content.

   
   

   ---

   Edited 3/27/2003 11:11:06 PM ET by Clay

1. 
   BOBABEUI | Mar 28, 2003 03:49pm | #3

   Clay,

   Thanks for the post.. The stock is kiln dried to about 6-8 mc, I have checked every board with my Wagner 205. This is the second load of lumber from this supplier, the first batch I sent back as it was so badly case hardened it was unworkable.. 

   I am trying to figure out if it's the supplier or the species. Seems like walnut maybe  more susceptible to case hardening than either cherry or mahogany, the poplar I got from the supplier is great.

1. 
   Kell | Mar 28, 2003 04:40pm | #4

   I've worked with walnut for years and found it to be friendly ordinarily, similar to cherry in stability.  (Mahogany is the best in this aspect though.)  Lately, the walnut I've been getting really twists and turns when resawing, so much that off cuts are winding up right in the burn pile.  They might be usable for pen blanks but I don't turn enough of those to keep 'em around.  Hate to waste any wood but especially one that is going for around $6 a bd ft these days.  I have a friend that is turning me on to some that is air dried (40 years or so) and I'll get a chance to see the difference.  I'll let you know what I find.

   Kell

1. 
   BOBABEUI | Mar 28, 2003 09:44pm | #8

   Kell,

   Thanks for the post. My experience so far has been much like what you have stated,  the stock twists and turns.. It's making me nuts.. This is my seconded go around for this batch of walnut from this supplier, so that's why I was asking if's just the nature of the beast or if my very well know and respected supplier (walnut specialist)  is having a very bad run at the kiln..

1. 
   kennedy136 | Mar 29, 2003 05:31am | #9

   Bob,

         I suspect that you are having problems due to your supplier rather than with the species.  I am fortunate in that I have an excellent supplier who lets me have first crack at his new shipments so I pick the best.  That said it is getting much harder to get good walnut due to the shortage of nice sized trees being available.  Smaller logs tend to yield less stable lumber than larger ones,which may have a lot to do with the problems concerning movement off of the saw subsequent to milling operations.  Also if you have a lot of sapwood in your wood that can also be an indicator  of it having been milled from small trees.  It is probably a combination of these factors combined with improper drying methods that are giving you headaches.  If you have nice stock though, there is nothing better to work with than walnut.  I use walnut, cherry, maple, mahogany and poplar in my reproductions and enjoy walnut the most, but if you have inferior stock it can be a real PAIN to work with.  However that is true of most species.  Good luck.

                                                  Mark

2. 
   Clay | Mar 28, 2003 05:40pm | #5

   [Seems like walnut maybe  more susceptible to case hardening than either cherry or mahogany, the poplar I got from the supplier is great.]                                                                                                                                    I think you are correct about this, perhaps your supplier (or whomever supplies him with the walnut) has less experience with walnut drying. 

1. 
   AlanTurner | Mar 28, 2003 07:44pm | #6

   I like walnut, but don't use it much.  It is the white oak that is case hardened for me.  From my supplier, everything else is fine, but I think he buys in the dried w/o.  It is a pain.  Resaw, wait till it moves, reflatten, cross your fingers.

3. 
   jonsherryl | Mar 28, 2003 08:04pm | #7

   Walnut, cherry and mahogany are all among the more stable of the major cabinet woods...but genuine mahogany is clearly the best in this regard. Here are the stats:

   Volumetric shrinkage, green to ovendry: Mahogany = 7.8%; cherry = 11.5%; walnut = 12.8%

   Tangential shrinkage: mahogany = 5.1%; cherry = 7.1%; walnut = 7.8%

   Radial shrinkage: mahogany = 3.7%; cherry = 3.7%; walnut = 5.5%

   Tangential shrinkage divided by radial shrinkage (T/R ratio): Mahogany = 1.38; walnut = 1.42; cherry = 1.92

   Basically, mahogany is superior in all respects, while cherry has a lower overall shrinkage than does black walnut...but black walnut has a lower tendency to cup or distort than does cherry.

   As for case hardening, it is amazing what a klutz at the controls of a kiln can do to screw up even the best of cabinet woods. 

1. 
   rod | Mar 30, 2003 03:11am | #12

     What is case hardening?  How can one tell it ?  What are the effects?

1. 
   jonsherryl | Mar 30, 2003 04:49am | #13

   Rod, unless the kiln operator is careful in following the correct drying schedule, i.e., the balance between moisture and heat toward the end of the process, it is possible to set up stresses in the wood...between the wood tissue in the interior of the board and the outer surface tissue. The board does not distort while these stresses counter balance each other. However, once the board leaves the kiln and cools down, when you attempt to rip it, you disrupt the balance between the stresses and the wood then has a tendency to either pinch the blade or splay out.

   Case hardening isn't that big of an issue in construction lumber that is normally used in the same dimensions as it comes from the mill, but in cabinet stock that is often ripped, planed or shaped to new dimensions, it gets to be a serious problem.  

2. 
   BOBABEUI | Mar 31, 2003 03:40pm | #16

   Jon,

   Is it a safe statement to say of that walnut is one of the more challenging species to dry correctly (without case hardening)?

1. 
   jonsherryl | Mar 31, 2003 04:47pm | #17

   No, walnut is among our better domestic timbers when it comes to being easy to dry. It has a very low tendency to distort or check and it's highly resistant to the fungi that cause bluestain. The wood's pigmentation can be affected by how it's processed...and it often intentionally is (usually by pre-steaming the stock before it is placed in the kiln for drying.) It's actually easier and quicker to dry than the more fine textured and denser species, like birch or maple...or (at least when air drying) those species that have high amounts of tyloses in the vessels, like white oak.

   Case hardening is pretty much a man-made problem in the sense that you can utterly destroy even the best of timbers, if you expose them to the high temperatures used in kiln drying and don't manage the humidity levels correctly. The kiln schedules for drying cabinet grade hardwoods involve taking the stock down to very low moisture content (in the 6% to 8% range) and then applying steam to relax the stresses while the wood is still warm. A good kiln operator (like an experienced sawyer) is a very valuable human resource in the modern lumber mill. It's almost an art and these professionals deserve a great deal of respect.

4. 
   fdampier5 | Mar 29, 2003 07:56am | #10

   I have well over ten thousand bd. ft. of black walnut and no problems so far..  most air dried over two or three years..

     Wonderful wood to work with and seems to stay plenty flat evan when used outdoors  (black walnut has wonderful decay resistant properties.. )

1. 
   jonsherryl | Mar 29, 2003 04:07pm | #11

   Darn it Frenchy, if you'd quit trying to corner the market with these large purchases, maybe walnut wouldn't be so expensive.

1. 
   fdampier5 | Mar 30, 2003 04:55pm | #14

   Now Jon,

     you know about my severe problem RE; woodaholicism if you were a true friend you'd come by once in a while and take some off my hands so I'd have room for more.. 

    you know my wife is pretty P.O'd about losing her parking spot in the garage so I can dry the most recent purchase of  black walnut. What with the wood in the living room and every other place in the house, she's beginning to think I may have a problem...... <G>

2. 
   DaveinPa | Mar 31, 2003 03:03am | #15

   Frenchy, talk about greedy. If you ever need to store any of that somewhere just let me know. I have worked with black walnut over the years and it's a joy to work with but your hand tools have to sharp to avoid tear out especially while planing. I have a problem that it irrates my throat and its sore for a few days after I work with it.  I must have some horse blood in me.

   Dave in Pa.