Primitive Archer
Main Discussion Area => Bows => Topic started by: NTD on October 06, 2009, 10:17:31 pm
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But why'd I break this one???????
I was tillering a red oak D bow and had it at a short brace of 3 inches and pulling to 16 inches when I started hearing pops and cracks. I looked the bow over and found a small crack on the back about 9 inches from the handle. (http://i95.photobucket.com/albums/l144/NDanforth83/072.jpg)
It ended up breaking completely shortly after taking that pic and this is what it looked like. Any ideas what caused the break?
Here's the Back
(http://i95.photobucket.com/albums/l144/NDanforth83/071.jpg)
(http://i95.photobucket.com/albums/l144/NDanforth83/069.jpg)
And the Belly
(http://i95.photobucket.com/albums/l144/NDanforth83/070.jpg)
Nate Danforth
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Noticeing that you are from Tucson,maybe it got a bit too dry.Us Desert dwellers often have the opposite problem as others on here.
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Hmm..didn't actually think of that. Maybe I should invest in a meter at some point?? I'm at a loss with this one. I felt I had great taper, no dips, no knots, straight grain...Hmm it'd make me feel much better if I could blame it on the humidity or lack thereof.
Nate Danforth
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I had a red oak board bow do the same thing...got it at low brace pulled it back some heard some pops and there she went....my guess is what Traxx said...too dry
-Ky
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It looks like you're using a quarter grain board. What does the grain look like on the edges. Sometimes the grain runs out the back. Something you can't see when looking a the back or belly. Ron
PS Go Huskers
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Oh, man...does this bring back memories...too many of them. Just had a bow blow up on me a couple of weeks ago. That will wake you up! But like you said, "If you ain't breaking them then you aint making them!!!" Sooooo true.
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M-P, you from the great state of Nebraska too??
-Ky
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Here are some pics of the edge grain. This was a rift sawn board.
(http://i95.photobucket.com/albums/l144/NDanforth83/118-1.jpg)
(http://i95.photobucket.com/albums/l144/NDanforth83/117.jpg)
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The way it broke my vote is with Traxx. Yes I have seen that before. :'(
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I wonder if exploding bows can just be down to the fact that we use wood as material ???
What i am trying to get at is wood is a natural material so we just cant be sure that there arent any tiny faults that will cause a blow no matter what we do.
I suspect its half the reason we love the stuff ;D
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i had a white oak board bow break on me a few months ago when tillering. the break looked almost indentical to yours. can't blame mine on low humidity though, summer in MN is pretty darn wet. mine broke as it was nearly finished, i was pulling it back to full draw (not the first time) and it just blew up without warning, i punched myself in the face. it was a little embarassing since i was working on it at the arcery range over my lunch break. It was so loud everyone at the range looked in my direction, all they saw was a guy rubbing his cheek and looking around like what the heck just happened, kinda funny in hindsight.
i agree with dwardo, sometimes wood just does squirrely things.
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go wide with oak, i find...
aren't you the laburnum guy ??? get happening with the laburnum wood, man, let's see more of those!
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also...i found that the sooner i could get the bending forces out toward the tips, the better...then i would finish tillering by moving toward the handle
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The only red oak bows that I ever made that didn't break were made from rough cut air dried lumber. The kiln dried broke like it was mad about something and would fly everywhere. At times I walk by the lumber rack at Home Depot and want to look but I know better now .That stuff has been bake like a cracker and the binders in the wood have been cooked till there crisp. If someone want to make a oak bow I alway tell them back it, with silk, burlap, drywall tape, rawhide, ect. my friend put his in a reverse bend and used the old spider wire of his fishing reel put it on with tight bond looked and shoot good that stuff is tough .Ain't broking ain't making sound like it was a statement made for oak self bows
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DIdn't read all the posts so I may be repeating. If you are having low moisture problems try a hickory stave it loves the low moisture conditions. Ron
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Its wild the way red oak snaps clean in two like that, ive had two bows do this, one was over drawn and the other was under massive stress and was rift sawn.
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I agree with Aires. I think you forced it, Nate. Looks like good grain on that board. Jawge
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Considering this happened in exactly the same way on a second piece I am convince it was too dry. As far as forcing I really doubt I did that as I never go above target weight during tillering. The target weight of this bow was only 45lbs. And I'm pretty ginger with my new bows during tillering. I alway exercise them well and always pull them to draw weight 30 times after wood removal before I judge tiller. I nurture my boards during the bow building process ;) ;D I turned out 3 d-bows previous to these two with near perfect tiller(according to you guys ;) ). I got 4 pieces of red oak at the same time back in september. I made 2 bows right away from those 4 peices. One of those 2 was a 64" long 1" wide red oak drawn to 28" @41 lbs if any of them were overstrained it was that one. These other 2 pieces sat in my entry way for the last 2 1/2 months. I thought about the fact that we have entered the dries time of year in one of the driest states in the country and the wood was sitting in the driest/hottest part of my house. When I made the first 2 we had just exited our monsoon season. The suggestions of being dry makes sense to me.
So I will reevaluate how I store my bow wood from now on.
As far as that Ipe, how long should I let it sit in a humid area to regain some MC before I start working on it? How many showers should it take with me :)??
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Hi Folks,
I'm coming around to believing the oak was too dry and or over stressed. If you try again with bamboo ipe I don't think you need to worry as much about the moisture level.
Ipe is very dense. I wouldn't expect it to change moisture content very fast and a bamboo backing should be pretty strong even if dry.
Kyler. Yes I'm a Husker born and raised, though I do live in CA now. Ron