Primitive Archer

Main Discussion Area => Bows => Topic started by: DC on January 26, 2018, 03:21:37 pm

Title: Post mortem please
Post by: DC on January 26, 2018, 03:21:37 pm
This is(was) my regular shooter. I couple of weeks ago the string slipped out of the nock and I dry fired it. I noticed a pinch beside a knot that was just under the belly. I scooped it out and put in a patch. I shot it for a couple of weeks, maybe 200 shots and today it broke. It looks to me like the back gave out but it's right at the end of the patch so maybe that contributed to it. In the first two pictures I kept it lined up with the grout line so you can relate front to back. The third picture shows how it looks like the break ran to the right until it hit that knot. Or is it possible that the break started at that right hand knot. I'm mostly wondering if the patch contributed but it looks like the glue joint is still solid. I didn't notice until I came in that there is a piece or two missing. I'll go out and look for them.
Title: Re: Post mortem please
Post by: JW_Halverson on January 26, 2018, 03:40:47 pm
Judging from all three pictures, but particularly the last one, I would say it broke.
Title: Re: Post mortem please
Post by: DC on January 26, 2018, 03:42:09 pm
And look what the string did. The nock point slid up the string stretching the serving as it went. Never seen this before. :)
Oh, I couldn't find any shrapnel.
Title: Re: Post mortem please
Post by: k-hat on January 26, 2018, 04:18:32 pm
+1 JW  :o
Title: Re: Post mortem please
Post by: DC on January 26, 2018, 05:10:26 pm
You guys are big help, thanks a lot ;D ;D ;D ;D ;D
Title: Re: Post mortem please
Post by: gfugal on January 26, 2018, 06:04:37 pm
Judging from all three pictures, but particularly the last one, I would say it broke.
haha
Title: Re: Post mortem please
Post by: upstatenybowyer on January 26, 2018, 07:03:56 pm
I don't know what happened Don but I'm sorry it blew. Yew is my #2 in explosiveness, #1 being ERC. Hilarious title by the way.  ;D
Title: Re: Post mortem please
Post by: burchett.donald on January 26, 2018, 07:24:37 pm
DC,
           I would say the newly introduced patch and glue may have not been bending evenly with the original belly causing stress on the back in that area or maybe a simultaneous collapse of the belly around the patch...Looks like a deep patch...I have used sinew on linear cracks but never open heart surgery...Like you said there was a knot there in the beginning....Glad no one got injured  (--)...I think JW was correct on his observation  ;D
                                                     Don
Title: Re: Post mortem please
Post by: DC on January 26, 2018, 07:27:52 pm
I've broken a couple in the last while. They were small knotty staves so I guess I should have been more conservative. I discovered about 2" of draw length by straightening out my form so I guess it was to be expected.
Title: Re: Post mortem please
Post by: Hawkdancer on January 27, 2018, 01:17:12 am
OPPs!  I hope that doesn't happen to me!  Got to agree with JW - it broke, fatally, fire up the grill >:D (=)!  Hope you are ok!
Hawkdancer
Title: Re: Post mortem please
Post by: chamookman on January 27, 2018, 02:32:53 am
Your second sentence said it all - "Dryfire"  (--). Does violent things to a Bow (and string). Blow Taps over it and start a new one  :OK. Bob
Title: Re: Post mortem please
Post by: Del the cat on January 27, 2018, 03:31:56 am
I think a string breaking is worse than a dry fire as the bow can flex the wrong way, damaging the back, maybe a little crease opposte whe the belly splintered.
There was doubtless more damage than you saw... the patch only got maybe 85% of the damage...
Del
Title: Re: Post mortem please
Post by: DC on January 27, 2018, 09:29:01 am
The bow originally had about 2" of reflex in both limbs. After the dry fire and repair the limb that broke was straight so, yeah, the more damage works for me. Thanks guys.
Title: Re: Post mortem please
Post by: Pat B on January 27, 2018, 09:42:50 am
I would guess that the dry fire is somewhat complicit and along with the patch(which may have changed the dynamics of the limb) contributed to the explosion. You possibly over drew the bow which I know for a fact will break a bow.  ::)  Sorry for your loss but these things happen with our fun addiction.
Title: Re: Post mortem please
Post by: ohma2 on January 27, 2018, 10:42:29 am
Post mortem conclussion dead,donate any vital organs to the learning pile.sorry for your loss.
Title: Re: Post mortem please
Post by: Jim Davis on January 27, 2018, 11:06:52 am
DC,
           I would say the newly introduced patch and glue may have not been bending evenly with the original belly causing stress on the back in that area or maybe a simultaneous collapse of the belly around the patch...
                                                     Don

I looks like the patch and glue line were not taking up the compression strain as soon as the unpatched  wood beside it. That is why I make my patches a different way (only needed them on a questionable stave, not repairs). I make my plugs a tight fit such that it is necessary to bend the limb backward slightly to push the plug into place, that way, the plug is sure to be compressing as soon as the unplugged wood. These images have been seen here before.
Title: Re: Post mortem please
Post by: DC on January 27, 2018, 11:13:26 am
I've got 30 bows hanging on the wall waiting to be used. Breaking one every once in a while is a learning experience. I always thought I may be overbuilding my bows but I think breaking one every once in a while is proving  that I'm probably not. The dry fire is extenuating circumstances though. Lessons learned by breaking bows seem to stick with me better. ;D ;D The arrow I was using had a shallow nock that I kept telling myself to fix. Shoulda listened to myself.
Title: Re: Post mortem please
Post by: High-Desert on January 27, 2018, 12:13:03 pm
I think it would be a good learning experience for all of us to see a picture of those 30 bows hanging on the wall.
Title: Re: Post mortem please
Post by: NorthHeart on January 27, 2018, 09:19:53 pm
Sorry for your loss regarding this one DC.  Im with Desert.  Lets see the others!
Title: Re: Post mortem please
Post by: DC on January 27, 2018, 09:39:55 pm
For what its worth :D
Title: Re: Post mortem please
Post by: Selfbowman on January 27, 2018, 10:00:50 pm
May it Rest In Peace. The rest look great though. Arvin
Title: Re: Post mortem please
Post by: gfugal on January 28, 2018, 12:08:27 am
I've broken a couple in the last while. They were small knotty staves so I guess I should have been more conservative. I discovered about 2" of draw length by straightening out my form so I guess it was to be expected.
Yeah longer draws make it so much harder If i had a normal draw length most of my broken bows would still be around today.
Title: Re: Post mortem please
Post by: Yorec on January 28, 2018, 08:41:09 am
This is why I come here - I learn so much!

My my ability to express an expert opinion remain right at that JW first expressed.... for now, but it’s very educational to read the other ideas and theories!  ;D
Title: Re: Post mortem please
Post by: bradsmith2010 on January 28, 2018, 03:08:08 pm
dry fire in the winter,, when moisture is down,,is pretty hard on a bow,, (W
Title: Re: Post mortem please
Post by: bradsmith2010 on January 28, 2018, 03:09:22 pm
there was probably more damage to the bow than the patch could fix,, (--)
Title: Re: Post mortem please
Post by: Springbuck on January 28, 2018, 07:02:54 pm
there was probably more damage to the bow than the patch could fix,, (--)

That's what I think.  The patch job looks good, but there may have been underlying damage you couldn't or maybe just didn't see.  I also prefer a patch more like Jim Davis posted pics of, but your work looked just fine.  Maybe the patch was slightly stiffer than the surrounding limb, which forced it to flex right near and running into (but under) the patch.

Looks like a spectacular break, though.