Broken elm bow, had a feeling this was coming (pics)

[ricktrojanowski]

One thing I've found is that a bow that loses weight really fast when tillering seems doomed to fail.  This happened again to me.  It was a simple elm bendy handle flat bow.  Once on the tillering tree, the bow lost weight at an alarming pace, coming in way under desired draw weight.  I tempered the belly in hopes of picking up some weight.  I took my time and tempered very thoroughly.  Possibly too thoughorly?  I then let the bow rehydrate for 4 days in humid conditions.  After letting it hydrate I got it back on the tree.  Only minor tiller adjustments were made.  Oddly enough no draw weight was gained.  However  after tempering  3" of reflex was induced, and nearly 2 inches remained after first session on the tree.  I had a feeling this bow was on it's way to be firewood, so for the next few days I exercised it on the tree, and it finally blew.  The first pics are of the bow right after tempering, and the following well.....

[Timo]

dbl bummer!

[juniper junkie]

the down side of playing with wood

[Josh]

Dang Rick sorry it let go on ya.  Looks like you had some time invested in that one too.  It was looking good. 

[ohma]

like said it will all break, but dont give up on elm, i can honestly say ive had less failure with red elm than any other wood ive worked.

[fusizoli]

If I see well the hot air flow turned on the back of the bow and treat it as well. It looking a tension failure for me.
I think this could happen more often on the narow limb bows.
Other wise that two elm bows I ve broken before had flat heat treated belly and crowned back.
 

[Mark Anderson]

I cut two elms down last summer and started several bows with them the first three blew up on me for no apparent reason. I finally got to looking closely at what was going on and it seems that the sapwood on these was really brittle. SUPER thin ringed and almost all early wood. Finally started chasing rings and found a good one and since then have had no failures. Elm is one of my favorites but these particular ones seem poor in the sap wood. Seems the last four or five years were tough on these trees.
Mark

[ricktrojanowski]

I think a couple of things happened. I pushed the limits on how narrow I made it. And you are right the back got a little brown in a couple of places.  I'm not going to give up on Elm. Just going to get back to an Osage one that I've had in the works for a while.

Josh, this one didn't really upset me when it broke.  I had my doubts about it early.  After breaking my sinew backed ERC last year no broken  bow seems to upset me.