# REALLY Dry air, cracking and shrinking wood



## chemfun (Feb 13, 2015)

I ordered some osage orange from ebay.  I wanted to expand from pens a bit.  A few of the blanks were cracked when I got them, but one cracked when turning.  As someone new to turning, I turned part of the box and then spent some time with the kids.  The next day, a crack had developed.  

I would LOVE to make a box for my loose tea.  When the temperature goes to -30 F and the air is really dry, what's the "proper" or best way to slowly let the wood dry?

Also, what would happen if I took such a box (with tight fitting lid) back to Michigan near the lake, in the summer, where it is warmer and more humid?  

How do I deal with these problems?


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## Dan Masshardt (Feb 13, 2015)

A moisture meter is a good investment.   I dont use mine as often as I should.   It's risky to assume dryness. 

All wood moves but end grain isn't quite as bad and if the lid and box are from the same piece, it should expand and contract about the same.  

In my understanding this is one of the reasons why boxes are usually end grain.


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## chemfun (Feb 13, 2015)

Got a URL to a good meter?  What happenes to wood when it travels from arid to humid?  I know wood is a sponge.  


Fwiw, I primarily use the pen plus and walnut with microcrystalline wax to seal.


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## The Penguin (Feb 13, 2015)

I've got this one, it works pretty good: Buy Lignomat Mini-Ligno E/D Moisture Meter at Woodcraft.com

for boxes - you want to start with as dry a piece of wood as you can get. Air dry to equilibrium moisture content is good enough, kiln dried is better. All wood moves as it dries, and most of them move different amounts in different directions. Mesquite is one exception to that - it generally moves the same in all directions.

if you're buying wood and having it shipped to you - look for WAX SEALED blanks - and leave them sealed to slow the drying process.

pens plus and microcrystalline wax are finishing products - not for sealing wood to slow drying.


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## chemfun (Feb 13, 2015)

Wax sealed will still dry?

My point about my finishing is with understanding. That they are not sealing them and the wood will absorb water when/if I ship the finished product from AK to somewhere else.


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## Dan Masshardt (Feb 13, 2015)

Don't assume wood that had been sealed is dry though.  The waxed ends can leave a thick piece wet inside longer.


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## Dan Masshardt (Feb 13, 2015)

chemfun said:


> Wax sealed will still dry?  My point about my finishing is with understanding. That they are not sealing them and the wood will absorb water when/if I ship the finished product from AK to somewhere else.



Wood will still dry 'sealed'.  The point is that wood drying too quickly will often crack.  Slowing  down the process helps.  

Finished product would will move regardless of what finish you put on.    

But and end grain box should all move together and not be a big issue.  End grain boxes are very common and not problem prone normally.  

You should continue to be concerned about using dry wood to start and lower your concern about the finished dry product having problems in this example - end grain boxes.   IMO.


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## Wildman (Feb 14, 2015)

Bought this General MM, for $10 back when darling of woodworking message boards.   Lowes puts them on sale from time to time but would buy at current price. 

Shop General Tools & Instruments Digital Moisture Meter at Lowes.com

If got money to burn this pin/pinless MM might be the ticket.

General Tools Spherical Pin/Pinless Moisture Meter with 4 in. Depth with Case-MMD950 - The Home Depot

All you really need from a meter is a ball park figure to work with. 

Some wood species should be near EMC before turning.  Some species of wood more forgiving only with experience can provide you that info.  Drying wood more art than science and no two pieces of wood from the same tree exactly the same.  So have a ball park MC when you first get the wood and again before turning helps.    

So always let wood you buy hang out for awhile before turning.  Beauty of having a MM is can get a ball bark reading when you get your wood.  You can do the same thing with kitchen, postal, or bathroom scale.  Weigh blanks when first get them when they stop losing weight ready to turn. 

End sealing is good because slows down drying process. Completely sealed wood does not allow wood to dry.  Wood loses MC or water weight by evaporation.  So do scrape sides of completely sealed blanks and allow to reach EMC before turning. 

http://www.uvm.edu/extension/environment/lumberdrying.pdf


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## Fay Prozora (Feb 14, 2015)

I think the sealing slows down the drying process. I bought my bowl blanks, they were sealed all over the whole piece of wood. After I turned the bowls just to get the shapes, then I brought them home and let them dry out in room temp for about a month or so and then took them back to the shop and finished them up. They turned out pretty nice for the first two bowls I had ever turned. So if you cut your own wood, maybe sealing it on the end grains would slow down the drying. I think if it dries too fast then it will crack. I found a box of wood under Uncle Dick's old lathe and they have cracks big time but maybe I can get some pen blanks out of then..


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## Bobostro61 (Feb 14, 2015)

When I get the wax sealed bowl blanks, I will rough turn them and put them in a paper bag with the wood shavings.  They will sit there for a month or two.  I then take them out and let them air dry at room temperature weighing them once every week or two.  I don't finish turn them until they stop losing weight.  That to me is a sure fire way of knowing they're dry.  I have had a few crack even in the bags with the shavings.  But, I've had many more uncracked than cracked.


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## jttheclockman (Feb 14, 2015)

Working with dry wood should be your goal whenever making any wood project. How to control moisture and wood movement is a challenge and always will be because of the very nature of such a natural product. Wood moves and some woods move more than others and direction of movement is also a key. There are many good articles and interesting talks on different wood related forums and doing a google search will help. Your answer is not so easily cut and dry(no pun intended) How wood is shipped is a crap shoot unless dealing with a reputable dealer that knows what they are doing. They more than likely will seal the wood to prevent what you had seen first hand. This then leaves it up to you to bring it to the desired moisture levels and to the use times. As mentioned a moisture meter is a handy item but not full proof. Like i said some woods are more prone to cracking by nature so no matter what you do will not prevent it. 

There are also many good articles an talks on woodworking and turning forums that deal with methods of drying woods. Again a google search and some reading time is all that is needed. Here is an article that talks about using Denatured Alcohol as a drying agent and how you can control the dry times. This is a very popular method with wood turners of bowls that use green wood directly from the forests. 

WoodCentral Articles & Reviews 

We as pen turners deal with such small blanks that moisture and movement really do not come into play as much as larger blanks. But if buying larger blanks and cutting them down then it does become an issue. Again there is no cut and dry answer to your question. Each species of wood has its own characteristics and unless you have used them alot then you become familar with them. But then again where they are harvested, how they are harvested and how they are stored and ship play a huge role. 

As far as your box thing, you do not say if you are turning it or using conventional methods and flat building it. Yes even though it is endgrain to endgrain if turned it still will move. To combat this make the connections loose and the theads deep if threading. If loose fit then it can always be sanded at a later date when introduced to those humid conditions. Sealing the wood will help. Use of shellacs and polyurethanes will stop some movement because it does not allow moisture to penetrate as much. But if there is moisture in the wood it still expand and contract. All sounds like wishy washy answers but that is the nature of using woods. Good luck.


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## KenV (Feb 14, 2015)

Good Morning Scott -   I am down in Juneau and have the same problem with wet wood.

Much of what is purchased by mail is wet to damp.  EBay is a good source of wet wood.  It is not commonly the best place to get dry wood.   The thicker the piece the longer it takes to dry.   

Added to that, the relative humidity in interior Alaska is more like southern Arizona and both are deserts (less than about 10 inches of precip a year).   

So your message has a couple of issues.    1 -- how to turn wet wood successfully  and 2 - how do we account an allow for movement of wood with seasonal changes.  

Item 1 -- yes you can turn wet wood into bowls and boxes successfully, but there are processes and tricks to doing it.   Lids have to be grain matched exactly.   You need either turn to finish thickness at one shot - or you rough turn and allow to dry before fininsh thickness.  You will lose some in drying both ways.   If you take a potty break, enclose the wood in a plastic bag and do not take long on your break -- it will move as you turn and crack if you leave it for any length of time.

2.  Wood moves and depending on what you are planning, you can adjust in your construction.   Loose lids on boxes are good where humidity changes a lot for example.  

By the way, I have found that moisture meters do not achieve the desired outcome in either Alaska or Southern Arizona.  They lack the precision to measure the interior situation.  A scale is a better guide.



Wet wood is turned to final thickness (thin) and once you start, you do not stop


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## Wildman (Feb 14, 2015)

Most wood vendors buy wood by the pound whether wet or dry.  When and where wood gets sealed in wax not important just know wood cannot reach EMC without air circulation & evaporation.  

It always better to buy wood locally but not always possible if looking for a specific species.  My chart tells me a proper EMC for this month wood stored outdoors in the month of Feb in Juneau would be 16.0% but if talking about Tucson 8.3%. 

A proper EMC is plus or minus one or two percent of intended use. So a wood project for inside would require a lower EMC than for something made for outside use.    

http://www.fpl.fs.fed.us/documnts/fplrn/fplrn268.pdf

Without getting too technical easy to see if want to make something for indoor use cut that outside stored wood EMC in half or as close to that as possible.  How you ask? Bring it inside and let it hang out before turning for awhile. If completely sealed in wax remove wax on sides but leave end sealed.  How long depends upon size might be couple week to couple months or more! Depending upon what you are making rough turning might be the ticket then again not. 

Here is a wet end grain turned Long Leaf Pine Hollow form set off to dry that will eventually have internal PVC threads so can PVC screw on top.


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## TellicoTurning (Feb 15, 2015)

I buy very little wood, when I do it's usually in board form, so moisture isn't that much of a problem.  Most of my wood is local from friends and neighbors who are clearing trees off their property or have had one fall from weather.... 

I turn most of my wood wet/green... I've actually turned some that was wet enough to actually sling water up my sleeve.  Turn it down to about 10-15% bigger than your finished size, soak it in DNA for a day or two, let it dry for a week or two and finish it...or  run it through a defrost cycle in a microwave for a few cycles, gradually turning up the heat and time in the cycle, let it cool between cycles and weigh it... you can dry a piece of wood in a day this way.   Some will warp, but for the most part I've been pretty successful using this method.  I use the microwave method more often than I do the DNA soak, but I do keep a 5 gal bucket of DNA that I use on occasion.  I have about 2 gallons in the bucket with a tight fitting lid to prevent evaporation... it's lasted over 2 years that way.  The DNA has turn black, but it's still working and still good.


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## chemfun (Feb 27, 2015)

Thank you all for the help.  I just revisited this thread again after ordering some 3x3x12" pepper mill blanks for my son.  I knew I was in trouble when the box seemed damp upon arrival.

Ken was SO right.  I unboxed the blanks to look at them.  I then made dinner and when I looked again, they had developed a few cracks already.  oops.

I immediately put them back in the shipping box to slow down the evaporation.  So far, no more cracks.  Fortunately my son is away for a month.  



When I turn the boxes I make the lid and bowl from the same piece.  I did notice that even a short "potty break" as mentioned would cause cracking.  I'm going to need to slow down and start turning and then let them dry some.  I was trying to make boxes with tight lids.  I'm afraid they will swell to much when shipped down states.


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## chemfun (Feb 27, 2015)

Had to get them off my phone.  The box lid only fits in a few orientations any longer.    Osage Orange from 4x3 blanks.  Sealed with Pens Plus.


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## mrtrenier (Mar 1, 2015)

I look at any sealed wood as wet wood.  If I am going to be spindle turning or bowl turning waxed wood, I write the day I purchased it and let it sit one year for every inch thick the wood is,  Worked for me so far!


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## chemfun (Mar 1, 2015)

Oi,  I'm going to need to look for kiln dried. We don't have storage space for 3 years of wood


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## mutley (Mar 3, 2015)

Just something you may want to try rather than waiting 3 years, or making your own kiln.
Contrary to most things I've read, I've recently found that drying small pieces of wood quicker rather than slower helps and almost reduces any cracks.  (I've only tried this on Sycamore and Birch). A few trees that had recently fallen, I saved the spalted parts I wanted (log form), left some as is & cut some to small board size. I noticed after a few days that they were all cracking badly. So with not much to loose, I cut some down to pen blank size and used the microwave dry method on a few blanks at a time.  Ended up with great results.

















Microwave drying was weigh each blank carefully, microwave a few blanks at a time on a paper towel for 30 seconds, let stand for 30 mins to cool down on paper towel, weigh them again. Then repeat the 30sec microwave / 30 min wait / weigh over and over until they stop loosing weight. At that point there is no moisture content left.  It seemed to take about 10 rounds in the microwave for the wood I have tried so far, and I've seen a 10 to 15% loss in weight.  
I specifically didn't seal the ends of the test pens and sent the pens to friends in different parts of the country & overseas. (Just send to different humidity). Asked all to report back if they see any cracks forming, So far so good. I'm just about to try it on an Oak tree that's fallen and I need to cutup.

I've read of people turning the basic bowl shape on green wood then using the microwave dry method on that (just so there is less mass), then finishing the bowl.


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## chemfun (Mar 3, 2015)

Would you do this for a piece that was 4x4x12?


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## mutley (Mar 3, 2015)

That depends, if I felt I had nothing to loose (as I'd loose the piece to cracking anyway), I'd absolutely try it, probably have to play around with the time in and out of microwave though.  If I felt I was probably going to loose it / didn't want to wait, I may try turning it to rough shape first, then drying it, then finish off on lathe.  If you search the net you will find plenty of positive and negative comments and articles on the microwave drying process.  All I can say is it's worked well for me so far.  

I'm sure there are so many variables in play that it would be easy to ruin a piece of wood.  So all I'd say is try it with something you don't have much time/money/love invested in first.


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