Working Crack?

[NYArrow]

In TBB Vol I there is a reference to tool marks, small cracks and splinters being ok in some instances. (can't find where I read it now) With that said...The bow I recently completed has had a small crack along the back from the day I completed it. It's only 3/16 long on the edge of the mid upper limb. I figured the bow would explode after shooting a few times but now has roughly 500 arrows through it and still has not failed or grown. I know I should back or wrap it however was wondering if it would be fine left alone? I have tried super glue to no avail. Just wondering if any of you guys have experience with this or any additional input.

[Pat B]

Even though your bow has not suffered yet, it probably will unless you address this problem. If you added super glue, this may be sufficient. Have you rounded all the edges? If not this may eliminate the crack.

[John Scifres]

I have made cracked bows that survived without repair.  But I don't trust 'em so I don't shoot them much.

[George Tsoukalas]

Superglue, wrap it with artificial sinew or B 50, etc, and put epoxy over that.  Wrap the corresponding portion of the other limb. That's what I do. Jawge

[No-sage]

Is it a crack or a check?  

Checks seldom cause any problem at all.  Cracks, on the other hand, are never good.

I don't shoot a bow well if I any doubt of it's integrity.

[NYArrow]

I had a feeling that's the response I would get. I suppose I will wrap it up. The super glue does not hold. After the glue dries the moment I draw the dreaded "click" happens cracking the super glue. I guess I'll wrap it with b-50 since that's really the only thing I have. After its wrapped I just coat it with epoxy?

[Pat B]

If super glue will not hold it when drawn once and it is a check, a wrap is necessary. Apparently it is in a working portion of a limb. If it is a crach the glue and wrap may or may not hold it and that will depend on where the crack is and how it got there.

FYI...a crack is broken wood fibers and a check is seperated wood fibers. Cracks are probably fatal eventually and checks are rarely fatal unless they run off the edge of the bow.

[SEMO_HUNTER]

Excellent definition and explanation Pat, I've experienced both and your advice is spot on.
If the super glue pops off when drawn that's a warning sign. I would back it with something.
You could always sand the back down flat and put some boo on it or another piece of hickory?
Maybe rawhide or sinew? Any of those should work fine and then the crack should be a mute point after it's backed.

[Pat B]

Will you post a pic of the crack and the ara where it is?

[NYArrow]

Here is the pic. Pat according to your explanation it would be a check. The odd coloring is the two layers of super glue under the stain.


 

[Pat B]

Was there a knot there? If not it must have been a swirl in the grain.
Being that it is on the back you could possibly grind down the back and add a hickory backing(also elm or maple backing)but short of that I'd say it won't last long.

[NYArrow]

There was what looked like the beginning of a knot. This only my second ever attempt so I figured the wood was worth the experience in trying at least. Yet it seemed to finish up nicely and shoot pretty well too so now I'm really hoping to save it. If I had a elm or hickory backer do I need to grind it down? Also will I have to remove the overlays or can the backing start below them? Finally there is a small lamination for my handle on the back (to add a bit of contour) would this need to be removed as well. I suppose the real question here is does the backing have to run tip to tip?

[don s]

i have the same problem with one of the bows i made.i wrapped mine with b-50 and put a few coats of CA glue on top of it. it held fine. but, the bow i did is a lightweight target bow of 35#. if a check is a seperation of wood fibers. then a check will run with the grain. correct? yours is going across the grain. don

[NYArrow]

Except there was a grain violation at that point. Or what is sometimes referred to as a run off. A "swirl" or pin knot was formed on the edge of this location making the grain run off. I think I'm just going to back it. Any ideas or experience with this would be appreciated.

[Pat B]

You can back only the limbs but you will get better results if you at least run the backing across the handle area and out the working portion of the limbs.  
  If you used TB glue you can heat the overlays and the glue will release. Clean off the old glue and glue it back down to the back of the handle.
  You will have to get the back pretty flat to get a good glue joint with the backing.

[NYArrow]

Ok, thanks Pat!