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Question about Walnut

Started by POSTON WIDEHEAD, December 05, 2011, 05:17:22 PM

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POSTON WIDEHEAD

 

 

I have 6 very nice Walnut slabs I sawed 2 weeks ago. I sealed the ends to keep them from checking. Each slab is 1 15/16 of an each thick x 22 inches wide x 5 foot long. How long do I need to let these slabs air dry before I can work with them. I wanna build some really nice country benches. I do not have a moisture meter.

Thanks, David

[fixed photo link - SwampDonkey]
The older I get I wish my body could Re-Gen.

T Welsh

POSTONLT40HD, about 2 years inside a dry place! if you bring it inside,say the garage or basement maybe less. it will drop its outside moisture pretty fast,its the inside moisture that takes time to leave! Tim

POSTON WIDEHEAD

Thanks T. Right now the slabs are under my shed where the rain mist sometimes blows under the shed. I WILL move them in the garage or work shop.
Thanks for the advice!

David
The older I get I wish my body could Re-Gen.

SwampDonkey

Nice slab wood. ;D If your air drying I would go with 3 years, but that's just what I do. I would also place it in a dry room for 3 or 4 weeks after planing (if you do plane it) before working it. Butternut I know dries pretty good, but it's got less water and much softer wood. Yeah, I know it's walnut. ;)
"No amount of belief makes something a fact." James Randi

1 Thessalonians 5:21

2020 Polaris Ranger 570 to forward firewood, Husqvarna 555 XT Pro, Stihl FS560 clearing saw and continuously thinning my ground, on the side. Grow them trees. (((o)))

LeeB

Indoor benches or outdoor? A year or less should be good for outdoor.
'98 LT40HDD/Lombardini, Case 580L, Cat D4C, JD 3032 tractor, JD 5410 tractor, Husky 346, 372 and 562XP's. Stihl MS180 and MS361, 1998 and 2006 3/4 Ton 5.9 Cummins 4x4's, 1989 Dodge D100 w/ 318, and a 1966 Chevy C60 w/ dump bed.

T Welsh

All my cabinet markers and serious woodworkers will buy slabs from me and then throw them in the kiln for a while to kick the rest of the moisture out of the inside,I will sell them green,but the good one that I keep,I will not let go until they are 3+ years old and thats what I tell them,they are air dried inside for 3 years. Tim

Ianab

A trick you can use to estimate dryness is to weigh them.

It wont tell you exactly how dry they are, just when they have gotten as dry as they are ever going to.

Balance a slab on a digital bathroom scale, and note the weight. Put it back on the stack. Next month, weight it again. It should have gotten lighter. Eventually it will stop loosing weight, and you can call it dry. You may even see the weight go up and down with the weather. This tell you that no matter how much longer you leave them, they wont dry any more.

Drying outside under cover should be fine as long as it's not really getting wet. The fresh air and breeze will help carry the water away. If you bring it inside, you are also bringing the water in, and so have to get rid of it. Once it's "air dry", it should be under 15% moisture, and then you can bring it inside for a couple more months to complete the drying, and not really have to worry about that small amount of residual moisture.

How long will this all take? Depends on so many different things. Species of wood, temperature, humidity, air flow etc.

If you leave it for 2 years they will certainly be dry. They will probably be dry much sooner than that, but the only way to know is to measure them, either with a meter, or at least weigh them to judge the drying progress. You might get them  dry in 12 months? Maybe a bit quicker if you build a "kiln" out of plastic and a small de-humidifier?

Ian
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

POSTON WIDEHEAD

Now ya'll talking......Now I'm learning!

I built some Red Oak benches while the wood was green. The benches are out on a porch on my cabin. They cracked just enough to give it some very good character. But I do not want any "cracking" in my Walnut benches.

These Walnut benches will be sold with me keeping the best looking one for my son, who is 9. Just a bench to hand down. I will use the scales. I have some flat top scales, used for weighing packages, I can use.

I feel better now....those slabs are to nice not to follow the right procedures.

Thanks ya'll!
The older I get I wish my body could Re-Gen.

T Welsh

POSTONLT40HD,This slab was 3 years old when I started in on it! 10/4 thick. when I  brought it inside to finish it it started to move :o It was not dried enough to come into a house,it was going to a customer that wanted to put it outside next to his fish pond ;D

   If you intend to sell these make sure you have them down in the 10% to 12% range and you wont have problems,even 15% should be alright.big slabs will suck up and give off moisture like nobodies business. Tim

POSTON WIDEHEAD

This may be the bench that inspired my idea to build some. I saw someone had a walnut bench in WOOD WORKING and I fell in love with it!

Sometime you just gotta have something like somebody else has! :D
The older I get I wish my body could Re-Gen.

WDH

Don't bring them inside yet because they may dry too fast, setting up internal stress that will crack them.  I am with Ian.  Leave them under the shed and they will dry naturally.  Here, they would be air dry in about a year or so.  If you leave them outside for a year under cover, then you could bring them inside and they will acclimate without splitting because most of the drying will have been done outside.
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

Lud

Kilin drying is a relatively recent development  in man's woodworking history .  Airdrying was all they had.  I stack and sticker in the bottom of the barn for a couple of years and  then hoist them up to the 3rd level under the black metal roof for the summer.  That gets them ready.

Find a way to kick it up a notch after the boards sat for a while.  Maybe a simple solar kiln ?
Simplicity mill, Ford 1957 Golden Jubilee 841 Powermaster, 40x60 bankbarn, left-handed

metalspinner

The best way I have come up with to dry thick slabs is to decide to build a project with them.  This automaticaly puts them on "The List" which is at least three years long.  When I finally get 'round to it, the slabs are dry. ;D
I do what the little voices in my wife's head tell me to do.

Brad_bb

With those wide slabs, doesn't he need some weight on them fellas?  I know with one inch slabs you'd need weight on them as they dry to keep them from warping, to keep them straight while drying.
Anything someone can design, I can sure figure out how to fix!
If I say it\\\\\\\'s going to take so long, multiply that by at least 3!

Den Socling

Walnut isn't prone to warp. No weight is needed. If you sticker a pack, you keep the stickers aligned so that the weight of the pack is supported by stickers.
If you are drying wide, flat sawn lumber (4/4), you might want some weight to prevent cupping.

T Welsh

Den, your right about Walnuts behaving while drying. I stack my good crotch slabs upright inside after sawing and watch them for the first 2 weeks and see what they are doing,you will get stress cracks and checking,but hey thats what wood does,I would much rather see it early and know its there than to start a project and hear a crack or a pop and find it later. I call the checks and cracks character. 

   The slab on the left cracked on top the one on the right has not,but is likely to do it,because it was the next cut off the log! Tim

scsmith42

Quote from: WDH on December 05, 2011, 09:39:15 PM
Don't bring them inside yet because they may dry too fast, setting up internal stress that will crack them.  I am with Ian.  Leave them under the shed and they will dry naturally.  Here, they would be air dry in about a year or so.  If you leave them outside for a year under cover, then you could bring them inside and they will acclimate without splitting because most of the drying will have been done outside.

+2

David, drying lumber safely depends upon several factors, including initial moisture content, temperature, relative humidity (RH%), species and thickness.

8/4 walnut can be safely dried as fast as 3.5% per day, but slower is usually better.  Among other reasons, slow dried walnut retains more pigmentation within the cells, and you end up with much more robust colors.

Your green slabs will measure around 85% MC, or thereabouts.  Until they get below 30% or so, you do not want to dry them too quickly, else surface checks will surely result.

The good news is that this is the best time of year to start air drying thicker slabs, because they dry more slowly during the winter.

By all means, for the first 9 months or so stack/sticker them outdoors but under cover (such as under an overhang).  Stack/sticker them so as to allow a nice breeze to flow through the stacks.  This means don't stack them length wise against a wall.  Around next June, you can add a gentle fan in front of them to help provide a consistent airflow.

By late summer, you should be able to move them inside to increase the drying rate (also with the fan on the stacks). 

To measure proper air flow through the stacks (fan generated), suspend a handkerchief behind the stack and look at the amount of deflection at the bottom edge.  Should be around 1" - 2".

Use straight, dry stickers and be sure that your stickers are perfectly aligned above one another. 
Peterson 10" WPF with 65' of track
Smith - Gallagher dedicated slabber
Tom's 3638D Baker band mill
and a mix of log handling heavy equipment.

Den Socling

Do you think slow drying retains more pigmentation or allows more time for oxidation?

scsmith42

Quote from: Den Socling on December 14, 2011, 12:55:42 PM
Do you think slow drying retains more pigmentation or allows more time for oxidation?

Den, that's a good question which I don't know the answer to....  From a purely guessing standpoint I'm thinking pigmentation because it may be more difficult for oxidation to take place deep within the wood cells, and a lot of air dried walnut seems to be much darker within the boards versus fast dried.

What are your thoughts?  Is the liquid that leaves a load of walnut in a vacuum kiln clear or discolored?  If the former, then I would think oxidation; if the latter, then pigmentation.

Thx.

Scott
Peterson 10" WPF with 65' of track
Smith - Gallagher dedicated slabber
Tom's 3638D Baker band mill
and a mix of log handling heavy equipment.

WDH

I am not sure what the process is, but the air dried walnut around here is beautiful with a really nice transition from sap to heart.  Colors like blue, teal green, vermillion, etc.  I just love that look.  Some people that come to buy walnut want it all chocolate brown with no color or contrast.  I guess that they have only known steamed, conventional kilned dried walnut.



Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

POSTON WIDEHEAD

WDH, what you said is what I'm looking for. I want the sap wood left on and HOPEFULLY the bark will stay on also.

I have sold Walnut slabs before and the customers ask me to cut it down to a board. After that, it just looks "store bought" to me. These slabs are 4 me and hopefully after air drying some different colors will show up/
The older I get I wish my body could Re-Gen.

Den Socling

Scott,
Walnut "juice" from a vacuum kilns is perfectly clear. Likewise, if you put freshly sawn Walnut into a vac kiln, it will look like freshly sawn Walnut when it comes out. So I tend to think the chocolate color is due to oxidation. Same as an apple turning brown.
Den

SwampDonkey

Yes the sap should be light or almost clear. You can tap butternut sap and it isn't brown or amber until you boil it down.
"No amount of belief makes something a fact." James Randi

1 Thessalonians 5:21

2020 Polaris Ranger 570 to forward firewood, Husqvarna 555 XT Pro, Stihl FS560 clearing saw and continuously thinning my ground, on the side. Grow them trees. (((o)))

scsmith42

Quote from: Den Socling on December 15, 2011, 10:22:24 AM
Scott,
Walnut "juice" from a vacuum kilns is perfectly clear. Likewise, if you put freshly sawn Walnut into a vac kiln, it will look like freshly sawn Walnut when it comes out. So I tend to think the chocolate color is due to oxidation. Same as an apple turning brown.
Den

Thanks Den - that makes sense.
Peterson 10" WPF with 65' of track
Smith - Gallagher dedicated slabber
Tom's 3638D Baker band mill
and a mix of log handling heavy equipment.

metalspinner

Swampdonkeys response has me curious about Dens walnut "juice."

Den, any chance you took a little sip of that juice?  What does it taste like? :D
I do what the little voices in my wife's head tell me to do.

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