Crack Master

I am one frustrated carver (with "carving sickness") that has lead me to believe that there are three givens with wood...It's cracked, it's cracking or it's getting ready to crack. Then Murphy's law kicks in and "It happens at the worst possible time". Jeez! One good thing is that I am becoming an artist at repair.

[Hugh]

Mike, you must be using green wood, and if so, most woods crack when drying. Cedar is the worst offender in my estimation. next basswood. A lot of trees are cracked even before they are cut down. Swaying in the wind, they crack when they are felled, or cut down. Lots of ways for wood to get cracked. Buying quality wood, kiln dried is the most expensive way, but seems the best. To air dry wood is a slow pains taking affair, and not as reliable as kiln dried. Cracking is generally caused by the uneven escape of moisture in the wood.

Thanks hugh. I live in Florida right in "Hurricane Alley" and have acquired a lot of fine wood from downed trees. You really know your stuff because the cause of my recent woes...red cedar. Splits like a ripe watermelon after it is carved. It was actually making audible cracking sounds as I was sanding on it. I was able to make invisible repairs on my life size juvenile great blue heron. I am pleased with the results.
Mike

[AlArchie]

Mike, Hugh has it right...a lot of wood, especially wood salvaged from storms is what is termed "wind shook" by the mills.

Looking at a cross section of a log you see the growth rings. Now, think of these rings as tubular "pipes" of wood, extending the entire length of the tree. In strong winds, or even when felling, the trunk of the tree is flexed past the shear point between these "tubes" and the wood separates along the entire length or at least in some sections. When the tree is straightened and milled, these "slipped joints" are hidden in the board. When you carve or otherwise work these woods, you relieve internal stresses and allow some of these "shakes" to separate.

That will explain some of the splitting in otherwise dry or fully cured timber.

Other internal stresses that may be relieved while carving include differences in weight bearing portions of a tree, ie. around where brances were growing from the trunk, or trees that have grown in a windy environment with winds prevailing from only one direction. This builds compression wood on the downwind side and tension wood on the upwind side. Wood cut from large brances have the same type of internal stresses. The down side of the branch has compression wood and the top has wood grown under tension. When you cut into these woods, the tension and compression are released and will cause warping or cracking, depending on the amount of difference in the two opposing forces.

Carving wet wood....well that's been pretty well covered.

Probably a lot more than you wanted to know.

Sorry,

Al

Wow! Al, what a wealth of information. I had no idea. I began carving when I had all this nice timber that had fallen. I bought a carving bar and chain for my chainsaw and found that I was okay at it. As I began to get into more detailed work, the cracks became a problem. Now I understand why. Darn! I have a large inventory of red cedar, palm (no worry with cracks there) and pine. Wish I would have known this before I started collecting. Thanks very much for the helpful information.
Mike

[Kenny_S]

I know a plumber who is a "Crack Master".
Then, My little bride tells me I am "cracked".

[Mryooper]

Originally Posted by Hugh

Mike, you must be using green wood, and if so, most woods crack when drying. Cedar is the worst offender in my estimation. next basswood. A lot of trees are cracked even before they are cut down. Swaying in the wind, they crack when they are felled, or cut down. Lots of ways for wood to get cracked. Buying quality wood, kiln dried is the most expensive way, but seems the best. To air dry wood is a slow pains taking affair, and not as reliable as kiln dried. Cracking is generally caused by the uneven escape of moisture in the wood.

Diamond willow does it also. I have found that it will crack even at the diamond. seal the ends and it just fractures within hours .

[Hi_Ho_Sliver]

haven't had a problem with basswood, anything else, I seal the ends with parafin wax and haven't had much of a problem there either

[Mr.T]

I carve cut -logs I find on the shore of the Hudson River here
in Haverstraw,N.Y.(30 mi. north of NYC). I work big and with
what I assume is green wood. I have several finished pieces which are cracking,and I want to know what I can fill the cracks
with when they are finished cracking. Can I make some saw dust out of the wood that is cracking and mix it with some sort of glue
so the crack won't be noticed? Other wise I'm going to have to
fill it and seal it and then paint it to look like stone. Mr. T

[Robson Valley]

I have given up on trying to control cracking in western red cedar. I've got log pieces that look perfect and others that could very well be shattered all the way through. The cracks I can see, I can deal with using a cedar-colored wood filler. I can hide a thousand sins with paint.

The cracks I can't see are the most discouraging. POP! and another fist sized piece cracked off late this afternoon. Have glue drooling all over the place. Wound up with a gouge wood chip glued to the top of my shoe!

Less than a month ago, I did a general clean up, looking for my table saw. Must have tossed 6-8 carvings in the wood bin. Just too frustrating, do something else (like sit here and rant.)