Bow goes Kaboom!

[Pappy]

Sorry about that,but we all know it happens, I have had a couple blow in the last few months,one was the Tom memorial bow,I really hated that. 
   Pappy

[Gordon]

Swedis, I'm confident a grain runoff was not the problem. I was careful in my choice of woods in this regard.

Acker, I also use Moso and I am confident the break was not a result of a compression failure. I am thinking, however, of trying a lighter core wood next time.

Thanks Pappy, I'm really sorry to hear about the memorial bow.

The more I examine the bow, the more I suspect that the failure was related to the powerlam. Specifically I did not make it thin enough where it feathers into the core. This left a tiny gap and given the high strain of 80#+ bow at 29" I think the break started with a delamination at that point. One thing I am learning about high-poundage laminated bows is that if there is a flaw in your design or execution it will be magnified.

[recurve shooter]

to bad, that woulda been an awsome bow!

[cowboy]

Well bummer!! That was a nice bow there too, sounds like you have it figured out though. Good to hear from ya Gordon! Haven't seen ya around in awhile..

[Keenan]

 Sorry to hear hat Gordon. That was a sweet bow, but pushing that kind of poundage, it's going to happen on occasion. Good that it happened on the tree and not in someones hands.

[Rich Saffold]

Gordon, I don't know if you can purchase the 1 1/8th" stock of Ipe where you live, but I often use this for a stiff handled bow since it won't flex nor does it need a powerlam...Then maybe I'll glue a few strips on the top of it more for decoration than real strength even though it might help a little..

Often I also like the Yellow Giant Timber Bamboo because it doesn't have the crown that the smaller diameter bamboos do, and when looking at how the bamboo failed it started at the top of the crown where the strain was the highest and not distributed along a flatter back..Heavier bows do change things..I prefer the smaller diameter bamboos on the slender ELB styles  since they do flex through the grip, and don't have the limb width that comes with the same poundage and length rigid grip styles..

One reason I mainly use TB 3 on these bows is if there is a failure in the bamboo it tends to go along the glue line and usually( almost always) save the rest of the bow, and it can be re-glued  The last bow I posted the belly was off a bbi which the bamboo had a flaw and it de-laminated, but it didn't take the rest of the bow with it. As a result the belly is still working. on perhaps the first IBI that I know of .  I think a glue can actually be too strong for how we use it..

Rich 

[PeteC]

Sorry about your troubles Gordon,I can relate. I don't believe your skill is the issue however,and I'm lookin' forward to seeing your next success.   God bless

[Marc St Louis]

Quite frankly I would blame the Bloodwood before anything else

[denny]

Dang Gordon , I thought you had a winner there. Oh well, It sucks some times. I have had it happen one too many times with boo and hickory. I have had several to look close at,but haven't truly figured it out as every wood is different. I use mosco and make the bow no narrower than1 1/2" at the fades. And I really focus on the reflex areas,this seems to work. That bend really puts the stress on the mid limbs. And I will find the week link at the powerfiber crown. And kaboom , had one blow at both mid limb areas at the same time,one end came back and bit me . still got the scar.And I might add I was at the back side of the bow in a vise on a tiller gig. Sorry to hear of your demise,good luck on the next. Denny

[Jesse]

Im not an expert but my guess is that you are right about it being the powerlam taper. Thats an easy place to get an air gap if its not faded down to nothing. I had a bow come apart that I was making for a friend and it was due to a very small spot that had a bad glue joint. With that heavy of a bow once the weak glue area fails the bow hinges and kaboom I dont think you would have had any problem at a lower poundage.  Godd luck on the next. We all know you can do it Thanks for showing us the break

[Gordon]

You're right Keenan. Better it broke while on the tree rather than in in front of Buffalo's face.

Rich, I'm not ready to give up on a powerlam, I think I just need to make sure to taper the ends so they are paper thin. Good food for thought on using TB for glue-ups.

Thank you Pete.

Marc, I'm not sure what to think about bloodwood at the moment. I'm getting mixed opinions on the value of this wood for bows. That notwithstanding, I'm not sure how the core could cause a failure like this.

Denny, your experience is why I use a tiller tree. The break was quite violent and could do bodily damage if someone was standing in the line of fire.

I think you're right Jesse. I have made several lighter weight bows with the same powerlam taper with no problems. I think the higher weight exposed a flaw in my execution. From now on I will be very careful to taper the ends to "nothing".


Thank you all for your supportive comments.

[Dano]

I know from hanging out with the glass bow guy's, that getting the taper on the power lam is critical, just as the tapers on a glass bow, the slightest gap could be a weak spot. Getting them paper thin takes some time and good tools (jigs etc...)

[denny]

Hey gordon , I whole heartily agree the bow tree is the safest. I can't believe some bowyers still teach new guys a stick is still okay. That experience, sure cured me. And a bow like the one you were building could be disastrous. Either way as it has been said, I don't think it was what you did. Denny

[Blacktail]

thats to bad Gordon...i guess back to the drawing board...now,if the yew wood fails can you blame it on Keenan  ....i live in central Oregon BUT i have western Oregon blood.   ...how would vm hold up to higher poundage..john