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I can maybe pick up some nice looking Siberian Elm but it's freshly cut greenwood.

What are the basics in dealing with greenwood?

Do we HAVE to kiln dry or will time cover it?

The pieces are 36" x 2" x 10'. How long might it take to air dry and be usable, stable...assuming Siberian Elm is ever stable (I'll study that some more)?

I worry it will check and crack over time...is that more or less likely allowing it to air dry?

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

General rule is about 1 year per inch of thickness air drying. Coat the ends with wax or paint to prevent checking.
I am pretty sure air drying makes for more stable lumber than kiln drying.

Disclaimer: I am a newbe to this, but did some reading and study to make decisions on some expensive wood I recently re-sawed.

My understanding is that air drying is best and helps avoid case hardening and warping. The thinner the wood, the faster and more even it drys since there is little distance from the center to the outside surface for the moisture to migrate. The problem with thick wood is the out side drys much faster than the inside which causes the out side to shrink while the wet inside will not. This causes cracking and warping. In fact, the sooner you cut your wood into veneers and stick it under substantial pressure the better your results will likely be. This gives you more control over the drying and shape (flat sticked) of the wood.

After cutting the veneers, either -
1) Immediately stick it, which is best.
or
2) Bundle it back together and wrap it with plastic to stop the drying as much as possible until you can stick.

Green veneer wood warps FAST (minutes or hours), so be prepared ahead of time with everything you need to stick it before you cut it. Or do #2..

Ed

Elm can really move around on you as it dries. It can twist, cup and warp and it's best to leave it
thicker than you would most woods because chances are you'll need to remove quite a bit of material to get it flat and straight once it's seasoned. It's never been commercially available all that much because of those problems
and the fact that it's been decimated in this country due to disease.

Seal the ends with wax and when you sticker it weight it down.

Regarding air drying vs. kilns: kilns begin with the humidity up and then lower it gradually. If you expose green lumber
to a low humidity environment when it's freshly sawn, it's going to check on you more than it would in the controlled environment of a kiln.

The only other advantage that kiln drying has over air drying is the speed at which you can process the lumber. Oh, and most wood comes from the kiln at around 7-8% moisture content. Depending on where you live, that may be hard to achieve.

PS: Even though the rule of thumb for drying is 1" a year, that can vary depending on your local climate and the wood that you're drying. For example, something's going to take a lot longer to dry in Florida where the humidity is high for a significant part of the year than Arizona. Also, wood air dried in Florida will never get as dry as wood dried in AZ no matter how long it sits around.

The elm I'm familiar with (not Siberian) would take a bit longer than average - 14-15 months or so.

Good stuff guys....appreciate the responses.

_________________
I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Here's how I deal with green lumber:
Apply a good spray of Boracare (Boric Acid) solution to both sides from a garden sprayer. Let dry a few hours.
(Note: I bought a load of Quartersawn White Oak which later was found to have Powder Post Beetles last year and had to unload my entire 1500+BF wood shed and treat it. Not fun. Proceed at your own risk if you don't think it's needed. It's cheap insurance and a fungicide too)
Anchorseal the ends.
Drill 1/8-3/16" holes through the board at the beginnings of any checks making a relief point to keep them from extending further into the board.
Elevate at least 12" off the ground and stack and sticker with 1" sticks every 12-16".
Wrap with ratchet straps every 3rd stick around the whole stack and keep very tight to keep the boards from twisting
Cover the top and keep out of direct sun.
Check every 2 months or so and rearrange the stack moving the middle out and outer to the middle if you notice big differences in moisture levels.

I would advise against resawing hardwoods green. I have had so many problems with potato-chipping that IMHO it just isn't the way to go. The method I settled on is to sticker the boards for at least a year, until the MC gets below 12%. Then it is safe to go ahead and resaw and sticker the thins for the final air drying.
Elm is not prone to excessive cracking, but it does shrink and warp a lot. For that reason, I would rip any wide plain sawn boards that contain the heart.

Here in East TN, air drying outside will only get the MC to around 10%. That is not dry enough, but thin wood will acclimate to the conditions in a humidity-controlled shop in a few weeks.

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John

Something worth exploring is making your own kiln. For the last batch of frames I made for my banduras, I used compwood which comes "green" and with a moisture content in the 30s IIRC. Following instructions on their web page I constructed this kiln using styrofoam sheets from the despot and a small space heater. The sides are held together with duct tape. I think the total cost was around $60 or so. You can see the space heater in the corner of the kiln.

When using the kiln, temperature was controlled by rotating the top to control how much hot air was escaping. I think I had the temp somewhere in the 120 to 150 range, can't remember exactly. Took about 3 days for the 3/8 to 1/2" rims to fully dry out to 7%. I bought a pin moisture meter to check but I'm now thinking that was a waste of $150 - If I wasn't so paranoid, I could have simply left the rims in there for an extra day. Borrow a moisture meter if you can but I wouldn't recommend buying one.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

yup, this (above) is correct, if put rather mildly.... I run a portable sawmill, and have sawed a fair bit of Elm. I have used it for turning serving bowls and for making cutting boards (great antiseptic properties with no finish required) Even when dried down as low as 8-10%mc, it will still surprise you when you go to machine it. I've found that drying it in free air (not kiln), by allowing approx 1 year per inch of thickness, then machining it "close" to final dimension, but leaving more than a normal amount of spare wood, then letting it acclimatise for several days (or weeks) in the shop, followed by final machining and almost immediate assembly will usually produce a product that won't move around too much. I have seen serving bowls turned, dried, finish turned, dried, sanded smooth and finished, only to keep twisting 2, 3, 4 years later, even when they are turned with no pith present.....

cheers - good luck!

John

I run a sawmill myself and have milled a fair amount of elm in the past and have found it to be the most unstable wood i've milled. It likes to cup , twist and bow alot during the drying process. It has to be held in place until dry or the boards will be badly twisted and cuped. Once air dried properly it is alot more stable but i wouldn't trust it on a guitar. I don't find it all that pretty anyways.Quite boreing actually.It is however hard to split when thick and that could be a plus.

Stuart,

We have and use 3 different kilns..... 2 hot air exhaust style and a vacuum kiln along with owning a Woodmizer sawmill. As someone who has built furniture for more than 39 years I wouldn't even consider non-kiln dried material. American elm is not a vary stable wood as far as movement, I can't speak for Russian. One of the things that a kiln does is also kills the bugs, etc. if raised to at least 140 degrees. We typically kiln down to 6-8 % before we remove it from the kiln. To advoid case harding a good kiln operator closes all exhaust down and allows the load to remain under heat and neutralize for several days just prior to the material exiting the kiln this removes most of the tension from the lumber and the case harding.

If you insist on purchasing this material I would recommend a solar kiln......... here is one ........ http://pubs.ext.vt.edu/420/420-030/420-030.html . Solar kilns are very effect and work....... slower during winter months but they still work.

Hope this helps,

Kevin

Haha...nah, I don't think so. You guys fairly convinced me that greenwood lumber deals should wait until I NEED a proper challenge. At this stage in my luthrie career I think I can do without another learning curve...especially one that might pay me off with stringed potato chips.

Thanks all!

_________________
I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

very useful thread! thanks chaps.

On this topic of green wood , drying wood isn't a secret but to help your success you need to do a few things to help yourself out for the best result. I was involved in Sawmills for many years and we dried with kiln and air. My feelings are the kiln dried is better and more stable. It also takes about a month process to kiln woods the old way of heat and air.
So if you have green wood , you should be able to place it where you can sticker it well and have some good air flow in a decently dry environment . I used to use my rafters in the old shop and I had a circulating fan that I could run when the heat got over 90 degrees. The wood should be stickered with at least a 3/4 inch sq piece. I liked pine for this but most any wood will do.
If the wood is very wet hit the fan on it after the wetness feels like it is off the surface. Don't cover the wood in plastic as this will create mold. Once it starts to dry allow a good year per inch and if you can keep in up in the roof rafters with a fan on it you will get it dry in a summer . The best you can expect is a 9 to 10% moisture in the wood in the mid Atlantic area . A kiln can pull down to about 6 to 8% depending on the kiln. Pattern Makers use Kiln Dried wood pulled to 6% for stability .

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I thought I read some where certain sappy woods used for stickers can leave stain lines on your wood. best to use a dried hardwood ,I like maple . Jody

Maple is good , so is white pine . yellow and jack pine will be a bit resinous. Also oak is good.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Probably a good decision. It can take over your back yard if you let it ...especially if you have a friend with a Woodmizer :

For stickers......
that go between the layers of wood to keep mold or sticker stain from occuring you can use the following.... ( have tried about everything but these for sure work )

1)Trex...... (man made material/lumber)
2)You can use Kiltz painted stickers ( stickers still need to be stable material then simply paint sticker...... Kiltz like you paint on the walls to hide kids crayola etc.)

We have found that maple in our area sticker stains when you look at it the wrong way.....

Other thoughts about drying:
even if air drying you need a level, stable platforms with girders properly spaced, height of stack should be at least 6" and there should be gravel or other porus material on the ground under the stack to allow for water not to be retained under the stack. The lumber should be stickered at least with 3/4" material stickered properly (at least every 16" on center) with kiln dried stickers, lumber stack should be covered from direct rainfall, no lumber left overhanging beyond 1' on the ends..... regardless the thickness......, use Anchorseal or similiar product on the ends, stack the thicker stock at the bottom and lighter above.

Lumber that is going into a kiln........ if it is a bad piece or section of material....... before going into the kiln when it comes out it will be even worse.......... often times even in air drying we will process or cut out bad sections of material......... takes a little more time but usually worth the effort.

Hope this helps someone.

Kevin