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Yesterday I received some wood with a crack at one end. This is ok, it's outside the area that I need for building but I was wondering if I should try to do anything about it while I have the wood in storage for the next year or so. If left alone, will this crack tend to propagate? Should I cut off the whole end of the board now? Should I try and close it up and glue it with CA? Any advice is appreciated.

Thanks,
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Since you are considering CA, I assume this is hardwood. There are a lot of variables that will affect how the wood will react as it acclimates. The major is the current moisture content of the wood. I assume you will have the wood stickered. If the crack will close now and the wood is a darker wood you can use CA. If a more reddish or light color wood I would use hide glue. So what species it?

I may be way off on this idea...so correct me at will!

I know with glass you can sometimes stop a crack by making a perpendicular cut/scoring at the end of it. Would drilling a small hole at the end of the crack serve the same purpose?

-Matthew

I have the same problem with a ¼" spalted maple electric top. I don't know what to do, the crack is expending...

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Francis Richer, Montréal
Les Guitares F&M Guitars

Thanks Michael. I should have said that the species is macassar ebony. The idea of drilling a small hole at the end of the crack has also occurred to me.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

I would certainly glue the crack if it will close tight. If this were a thick plank of wood I would bind the end together tightly with wire or a metal strap. Since this would destroy a guitar set, so you could simulate this by gluing a narrow strip of wood across the end of your ebony. If it's no wider than the crack it should also fall outside the guitar outline.

Peace,
Sanaka

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...imagine there were no hypothetical situations...

I would glue it up, I would not bind it tight with metal straps. Glue it and sticker it that is all that is needed. If the wood needs to move it needs to be allowed to move. Binning it with metal will likely cause more checking and cracking if it needs to move to acclimate to the environment. Plus you can get galvinistic staining with some woods when in contact with metal.

Also, if what's causing the crack is some internal stress in the wood that originates further up, then drilling the relief hole might simply result in there being a hole part way along the crack! I think cracks in glass propagate in quite a different way than in wood, as glass is much more homogeneous.

Peace,
Sanaka

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...imagine there were no hypothetical situations...

Drilling a hole should definitely help,the hole is less of a stress riser. The sticky part is how do you know where the end of the crack is located..? Miss it by even the smallest amount and you may as well have not drilled at all.

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A person who has never made a mistake has never made anything!!!

Just a few things you might try. Hard to tell exactly the cause.
End checking is usually a result of wood drying too fast. It is possible the ends are not sealed well and may have had a higher than normal moisture content and dried very quickly. The ends will ALWAYS dry faster than the inner wood causing checking like you describe.. Put your wood in a plastic storage container with a slightly dampened sponge for a few days and see what happens. It may close up a little. Seal those ends good with wax, enamel paint or anything that doesn't breath. Put it back in the container until sponge is dry...then store at the usual humidity you plan on building at.
One other possible factor. If the end of your wood was cut near a knot or log imperfection the grain stress of directional fiber relief can cause a check. Most of the time the check will only travel as far as the grain stress.
I would also trim off any excess wood you are not going to be using as stressed grain fibers on either side may also be pulling the crack apart.
Good luck
Kent

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Wood Creations by Kent A. Bailey
EXCELLENCE IN SCULPTURE, CARVING, LUTHIER, ARCHITECTURAL MILLWORK AND DESIGN

http://www.kabart.com

If left alone, the crack will most likely contunue on so i would glue it .This will probably keep in in check until you use it, however as soon as you cut past where you glued it later it could still continue on if the crack is from tension in the board where the tree was under tension when it grew, which is almost impossible to stop.Trees under tension when they grew will create boards that will crack as soon as the board is milled and the supporting wood is taken away by the milling process.I would keep an eye on it for a while once you start to use it for that very reason because it might continue to crack when the glued end is cut off.