Tree trunk tables?

[Wood_workur]

I've been given the opportunity to get my hands on a piece of catalpa, its 4 feet in diameter and about 5 inches thick. Obviously its a cross section of a tree trunk.

The obvious use for this is to make a table. That's what it was intended for, but the person who has it doesn't want it anymore. Its a rough chainsaw finish. A few years ago we had two trees cut down- a hickory and a swamp oak, and we kept some cross sections of the trunk in hopes of making a table out of them. Unfortunately they were left out in the yard for too long and have rotted a good bit and have a good bit of checking going on (though maybe if they were cut they could still be used). This piece apparently has been air drying for the past 20 years or so, so its not green.

So, the question is, if you had this piece of wood, assuming it is in good condition (as in usable from the middle to the bark) what would you do with it? I'm not sure that I've got the room for a table made from the entire thing, which makes me wonder if I'm better off letting someone else have them (who will use the whole thing for a table) and then salvaging what good wood is left for a table or 3. We do have 2 or 3 good sized cross sections that could easily make 4 end tables.

[scmhogg]

Alex,

First thing. Never ever turn down good wood.

Look at the pics on George Nakashima's web site.

http://www.nakashimawoodworker.com/f...ew_furniture/3

Steve

[LCHIEN]

Alex,

First thing. Never ever turn down good wood.

Look at the pics on George Nakashima's web site.

http://www.nakashimawoodworker.com/f...ew_furniture/3

Steve

so alex, looking at those, the rotted pieces you have may be good after all.

[Jim Frye]

If its a cross section cut...

I would expect it to split badly as it dries due to shrinkage. You may be able to prevent it from splitting by coating both sides with PEG or heavy paint to slow the drying. Every trunk disk I have seen has split from the center to the edge as it dried, regardless of thickness. Check how turners dry their bowl stock to keep them from cracking.

[cabinetman]

I'm with Steve on this one...if it's free take it.
.

[LCHIEN]

its extremely difficult to keep the cross sections from splitting.
The reason is that the wood is made of hollow fibers basically. Considering the trunk in its living vertical orientation, the fibers run up and down.
When the fibers shrink after the tree is dead, the length of the fibers does not change much, but the diameter does. This is how normal lumber reacts, the length along the grain shrinks the least and the width and thickness of the lumber shrinks more.

Now if you think about a whole bunch of straws tied together in a bundle, there will be many more straws on the outside layers than the inside. As they all lose moisture and diameter at the same rate (moisture leaves thru the open or cut ends) then the ouside layer shrink much more in total than the inside. THe unequal loss of volume vs. distance from the center is what causes this checking.

So it takes very careful prep and drying to prevent this from happeneing.

[Daryl]

I would expect it to split badly as it dries due to shrinkage. You may be able to prevent it from splitting by coating both sides with PEG or heavy paint to slow the drying. Every trunk disk I have seen has split from the center to the edge as it dried, regardless of thickness. Check how turners dry their bowl stock to keep them from cracking.

I would expect splitting too, but he says it has been drying for twenty years.

[Sid]

Not sure I agree

Now if you think about a whole bunch of straws tied together in a bundle, there will be many more straws on the outside layers than the inside. As they all lose moisture and diameter at the same rate (moisture leaves thru the open or cut ends) then the ouside layer shrink much more in total than the inside. THe unequal loss of volume vs. distance from the center is what causes this checking.

I'm not convinced that's the explanation for the checking. Take a Xerox copy of the end of the bundle of straws, but set the magnification to 80%. All the straws shrink at the same RATE, and there is no distortion of the bundle's shape, even though the outer ring circumferences did shrink more than the inner ring circumferences in absolute length. No change in shape, no internal forces, no checking, if all the straws shrink at the same RATE.

I'd suggest two possible alternate explanations. First, the outer sapwood (sap=wet) probably contains a larger initial moisture percentage than the core, so it shrinks more per straw (higher rate) than the heartwood, causing shape distortion and internal forces that result in checking.

Second if not all the moisture is lost through the straw ends, but some is lost through the outer rim, the outer straws will lose moisture more quickly than the inner straws, again leading to checking.

Sid

[Wood_workur]

First thing. Never ever turn down good wood.

Yea, but from what I've found its soft, weak, and brittle, about the same as white pine. I'm not exactly sure if this would be ideal for a table top, especially with the grain running vertically.

[ironhat]

<snip>

So, the question is, if you had this piece of wood, assuming it is in good condition (as in usable from the middle to the bark) what would you do with it? I'm not sure that I've got the room for a table made from the entire thing, which makes me wonder if I'm better off letting someone else have them (who will use the whole thing for a table) and then salvaging what good wood is left for a table or 3. We do have 2 or 3 good sized cross sections that could easily make 4 end tables.

If you haven't the room for the entire cross section why not try to use the deepest split as a cut line. You will have an arc on one side and a straight edge on the other. Now you can have a nifty, primitive bench for the porch or make a base per George Nakashima's site and use as a coffee table. Hmm, that may not work because any split will cut the slab in half which may or may not be big enough for your. Your call.

[Wood_workur]

If you haven't the room for the entire cross section why not try to use the deepest split as a cut line. You will have an arc on one side and a straight edge on the other. Now you can have a nifty, primitive bench for the porch or make a base per George Nakashima's site and use as a coffee table. Hmm, that may not work because any split will cut the slab in half which may or may not be big enough for your. Your call.

That is a good option.


What would you guys do about legs? I can't imagine plain old straight legs looking good on something like this.

[crokett]

I would do natural legs. As long as the slab has bark on it, find some appropriate stock that has bark on it as well. Dowel the ends and drill the slab for the dowels.

[cabinetman]

You could use dimensional lumber and create a joint to the slab, like a M&T or dowel, or a loose tenon. Then clad the lumber with "woody" stock to go along with the slab.
.