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Howard Skillington
02-19-2018, 1:16 PM
I have just purchased a load of walnut. It was milled to 4/4 and 8/4 about four years ago, properly stacked and stickered in a dry shed and, despite this being the rainy season in North Carolina, now has a moisture content of only about 12%.
Unfortunately, the board ends were not painted, so there's plenty of checking, but the wood is still a bargain - wide boards with almost no sapwood.

I have not managed air-dried lumber before. I will need to keep about half of this stuff properly stacked outside, but want to bring the other half in to begin acclimating to my shop with the relative humidity maintained at about forty per cent. Should I trim off the checked ends and paint them before stacking them, stickered, inside? Should I bother to paint the board ends of the lumber that's staying outside?

Lumber in my shop generally reaches equilibrium at around 7 - 8% Any guess as to how long that's likely to take for this stuff?

John K Jordan
02-19-2018, 8:03 PM
I have just purchased a load of walnut. It was milled to 4/4 and 8/4 about four years ago, properly stacked and stickered in a dry shed and, despite this being the rainy season in North Carolina, now has a moisture content of only about 12%.
Unfortunately, the board ends were not painted, so there's plenty of checking, but the wood is still a bargain - wide boards with almost no sapwood.

I have not managed air-dried lumber before. I will need to keep about half of this stuff properly stacked outside, but want to bring the other half in to begin acclimating to my shop with the relative humidity maintained at about forty per cent. Should I trim off the checked ends and paint them before stacking them, stickered, inside? Should I bother to paint the board ends of the lumber that's staying outside?

Lumber in my shop generally reaches equilibrium at around 7 - 8% Any guess as to how long that's likely to take for this stuff?

Howard,

I'm certainly no expert but I have a sawmill and have cut and dried boards and turning blanks. I like to coat the log ends with Anchorseal when green before sawing and stickering then when partially or mostly dry might I bring them inside, cut off any checks and coat again. For thick boards and blocks intended for turning stock I usually seal immediately after cutting from the log, then when almost dry I trim thin slices from the ends and bend them to reveal any hidden checks then continue to trim until any checks are gone. Then I seal again and let dry some more. This sounds somewhat like your situation so I'd probably do the same for those brought inside.

Since yours are already well air dried I would personally do the same for the outdoor boards - trim the ends on all of them and coat with sealer, bring them inside as space permits. If a wide board had just a single long crack or two you might even saw down the crack and save the length, assuming you could use some narrower boards also.

If the checks are tight I might seal over them then then keep an eye on them until the MC comes to equilibrium indoors. Fortunately, walnut is usually a pretty stable wood compared to some others so they might have already checked as much as they will - I have some 8/4 and 4/4 walnut slabs air dried outside then brought indoors with no degrade. I have no idea how long it will take to reach 8%. That's drier than I keep my shop.

I think paint is not recommended for sealer, especially latex paint. One of my older drying books recommended aluminum paint. I'm happy using the Anchorseal. Yikes, time to order some more. I bought a 55 gal drum years ago and I'm down to the last few gallons.

I would certainly sticker them indoors so the remaining moisture could escape.

If air dried outdoors be alert for evidence of powder post beetles already in the wood. They can stay inside for years. Look for fine powdered "frass" on the surface.

JKJ

Howard Skillington
02-19-2018, 9:22 PM
I very much appreciate your thoughtful and thorough answer. Trimming checked ends before sealing makes sense to me. I've just put Anchorseal on tomorrow's shopping list.

Danny Hamsley
02-22-2018, 4:39 PM
Latex paint is not useless as an end sealer, but it is close. Invest in some Anchorseal.

Tom Bender
02-22-2018, 8:24 PM
I have had good success with latex paint but it takes a few coats. Worked on Sugar Maple, Hickory and White Oak sawn 8/4 and stickered in my garage for 2 years. No end checking at all.

Scott T Smith
02-22-2018, 9:33 PM
Howard, end sealer is only effective if applied within 3 days of a fresh cut on the ends of the boards (or logs). Unless you have major splits, I don't think that you will gain anything from applying end sealer to lumber with a MC% of 15%.

As far as aclimination, your 4/4 BW should be below 10% in about 3-4 weeks in your shop (measured at the core of the boards); faster if you have a fan on them. The 8/4 will take around 2 months.

Howard Skillington
02-24-2018, 2:58 PM
I got a quart of Anchorseal 2 (@$21/free shipping/Amazon Prime) and it seems to be a good product. I am cutting the checked ends off and applying it immediately.

Howard Skillington
02-24-2018, 3:02 PM
That timetable seems to be confirmed by my moisture meter, which is showing the wood in the shop as losing about a tenth of a per cent moisture per day.

Jim Andrew
04-18-2018, 7:57 PM
You are wasting your Anchorseal by using it at this late date. Put it on a fresh cut log.

John K Jordan
04-19-2018, 5:54 PM
You are wasting your Anchorseal by using it at this late date. Put it on a fresh cut log.

We will have to disagree on that. I do agree that sealing is the first line of defense on green wood. However, I've cut and dried many thousands of turning blanks and by experimentation I found that Anchorseal can help in some cases, even if the wood is "mostly" dry. I think even a minor moisture gradient, especially deep inside thicker wood and particularly with some species, can still start and propagate cracks. Walnut seems pretty well behaved but some wood is horrible and can be dry and cracked on the ends and still damp on the inside and the end cracks may well continue deeper until the shrinkage stresses from drying are finally equalized. What I usually do when I find end checks/cracks, even on occasional blocks that were sealed when wet, is cut the cracks away, test for solid wood by removing very thin slices until bending one no longer splits, then I seal immediately. I seal even if the wood has been air drying for several years.

I used to seal only when wet. Now I seal the ends of almost every cut (for example, when cutting a section from a long piece) unless I know the wood is at EMC. (I write the date on each piece for a clue.) I might not seal if the cross-section dimensions are small or for certain species like eastern red cedar.

This applies more to turning blanks than lumber, but someone might be interested: For some species and figure I seal more than just the end grain - all around for burl, the entire face that shows crotch flame, and any wild grain. Some species like dogwood shrink so much and since the heartwood shrinks far less then the sapwood I seal the sides of turning blanks that have both heartwood/sapwood exposed, otherwise it will usually crack horribly. For wet dogwood, holly, and a few others I also seal block faces that are mostly bark-side transverse sections since that is where the shrinkage is the highest. This shows my method for sealing the sides dogwood turning squares and blocks:

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I think of sealer like cheap insurance. A little goes a long way so if applying it does nothing, not much investment is wasted. If applying it prevents cracking, it's a very good investment!

JKJ