Thick wood: drying, stabilizing, and working

[TheFatBaron]

Once upon a time, a cherry tree in my back yard lost half of a pretty big tree limb. Turned out, one of its branches broke off, some water got in, and a pretty big section of it rotted out. Fortunately, when we cut the other half down, we were able to save a couple nice pieces... maybe 10" in diameter and between 12 and 18" long, so really, enough for, say, a couple really chunky coffee table legs.

As I understand it, it's at least 1 year per inch of thickness to air-dry wood, so I'm looking at... what, a decade for these to dry out? Short of finding a lumber yard willing to let me toss these in their kiln, do I have any other options? I've already got some checking on the ends, so I was thinking about drying it for a year or two to get the worst of the moisture, stabilizing any cracks with epoxy, and building the tabletop to account for any additional shrinkage.

Thoughts?

[AceHoleInOne]

Are the log's sawed into board's yet? I'm not up on air drying cherry. But I think if you don't saw the logs down to boards, basicaly you will develope deep crack's through the logs. I know this happens to Maple, they were 12" log's going become bowls. Don't ask.... ...ummm.....errrr....forgot about them in the back of the garage and they cracked all to hell. I even sealed the endgrain and removed the bark so bugs whouldn't get into the wood.

-Ace-

[TheFatBaron]

No, I haven't sawed (sawn?) them into boards. I suppose that's one option - strip the bark, square up 2 sides, then slice on a bandsaw to 2" thick (or whatever), then re-glue when it's time.

[Howtoworkwood]

The first thing you really want to do is seal the end grain. The structure of the wood is effectively like straws with the opening at the end grain. This means that the ends dry out before the middle which leads to a steep moisture gradient and severe warping and cracks.

Just paint the ends with any kind of sealant you can get your hands on, I've even just used paint before, anything that can block those openings.

If the ends/outside of the wood dry out too fast whilst the core remains moist then this will lead to problems such as case hardening and warping. Cracks are guaranteed to form in a log due to the differential shrinkage rates between tangential and radial wood but they can be minimised by creating the shallowest moisture gradient possible.

The aim is to have the rate at which moisture is moving from the middle of the wood to the outside of the wood exactly match the rate at which the moisture at the surface is being evaporated away. This is the only way you can minimise those cracks.

I would cut the log down into usable lengths, if it is possible to reduce the section size by sawing them into boards before hand then do so as this increases the surface area and will allow them to dry out faster. Saw them bigger than you want so you have room to machine them square again after they inevitably move.

One final thing, air drying is only going to give you a moisture content of about 15% at best so when you make nice table legs and move those pieces into your house they are likely to crack and move again as your A/C or heating will dry the wood out to something more like 6-7%. If you want to allow for this then store them in your garage for a bit once they are air dried then move them into your house to acclimatise.

I hope that helps!

[TheFatBaron]

It does - I haven't sealed the ends yet - it's been about 2 weeks, so hopefully no permanent damage has been done. I know I need to do it though... just been a rough couple weeks.

At this point, I think my plan is to strip it down, square 2 sides and see how bad the checking it. if it's bad, then it's wood for the smoker. if it's salvageable, then I'll cut it down (though into thicker slabs), seal the ends, and dry it. It seems like that's a going to minimize any further damage.

And yes, case hardening sucks - I do some meat curing on the side, and it's equally painful for that.

[AceHoleInOne]

Hey Fat:

No, I haven't sawed (sawn?) them into boards

Either is fine.

-Ace-

[wdwerker]

Seal the ends soon! Trimming etc can be later but get those ends sealed for best results.

[TheFatBaron]

I forgot to follow up on this. A while back I bit the bullet and rented a chainsaw from Home Depot to get the bark off (and cut the dead stuff up into more manageable pieces). It's hard to get a good perspective. It's now sealed & bug sprayed, covered, and drying and drying on my back porch until winter hits. I'll be getting a least a couple project pieces out of this - end table or entertainment center legs, or something like that.