Primitive Archer
Main Discussion Area => Bows => Topic started by: Diligence on January 30, 2010, 12:31:27 am
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Okay gang - been lurking for a long time. I've been shooting my first bow, and it has developed a problem. I need your help.
The specs:
-60" Nock to Nock
-self bow of choke-cherry
-bend thru the handle
- 45# at 26" and 53# at 28" (tillered to 28")
-approx 1.25" wide at handle by 0.75" thick
-even taper (but thicker at the knots) to 7/8" wide by 1/2" thick at the nocks (approximately)
- this bow has seen maybe 200 shots, tops.
- it has about 3" of set (resulting from me tillering it when it was still a bit green)
- no belly tempering, no backing, no ring chasing (just removed the bark)
edit to add....this bow has a natural, but slight recurve at the tips...
It's developed some belly chryssals/frets in one section of the top limb and it has also developed a compression fracture adjacent to a knot (in the same location as the chryssals). I know that I was starting to get a bit of a hinge in this area during tillering, but thought I had gotten it out. Poor tillering caused this I think.
Here are the photos:
-full draw (the spot of concern has a bit of black tape on it)
-the pencil is pointing to the fracture and the area with surface chryssals is only the length of the pencil
-several close-ups showing the details (note that just above the fracture is a couple of tool marks, they look like dents)
My question:
Do you all, in your combined wisdom, think that this particular compression fracture should be fixed?
If it should be fixed and not ignored (with prayer for the best), should I use Dean Torges' method? (ie. cut out a sectiopn & glue in a patch) Or, would the rawhide patch method (per Gordon's bow build-a-long) be a better option.
I really, really want this bow to last and not blow up while shooting on the line in my new archery club. Mr. Murphy definately showed up last night. My first time at a club, full of ONLY compound shooters, and my bow starts to break.....wonderful.
What do you think?
Jaye in Calgary
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Now remember ...you asked....... 8)......Now I think that Choke Cherry is a poor wood to begin with...It has a tendency to fret no matter what you do....if the Tiller isn't Spot On...It will tell on You...and it did...Here is what I see...and I say this knowing I may be wrong...but this is my Opinion....The Top Limbs Tiller is way out...making the Spot with the Knot work way too much...and it could not take the Pressures of doing all the Work... :P...So it fretted...and Fractured on You...Now for the Fix...I would soak the Knot with Super Glue...and retiller that Top Limb to get the Outer Part of the Limb working like the Bottom one is...I would either Wrap the Chrysalled Area with Sinew and Hide Glue...or a Rawhide wrap to slow down the deterioration of this Spot...nothing will save it forever...JMO
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I am gonna agree with EL D. He has helped me alot and by his photo it shows you need to adjust the tiller on the top limb. Now about the chokecherry, I worked a piece today. I cut some a few months ago and split a month ago, I was trying a small kids bow just to see how the wood behaves and it seems very soft unlike any other wood I have worked. So I think it would fret very easy. Plus the sapwood is supposedly weak in compression and it looks as if that is what your bow consists of.
I would wrap the freted, knots with sinew and hide glue, and retiller and see what happens.
Tell
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I think it's going to go bang eventually...
In the pic where you have the pencil, you can see the grain bending out to the left, you havn't allowed the grain to go out and around the knot (E.G The left edge of the bow should bulge out wider where the knot is) and that's been a contributory factor.
The other crysals you could brobably live with, but the crack to theft of the knot looks like an accident waiting to happen.
Just my opinion of course...
To improve it, do like the other guys say, but also take wood off the lower limb, to allow this to flex more and take some load off the upper.
If it's any consolation, I just made a little experimental bow backed with rawhide which is chrysalling a tad...mind it is my 'one hour bow'.
You can always have it as a 'lookin at' bow rather than a 'shootin' bow ;)
Del
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Me I would either shoot it till it fails or hang it on the wall, then make another.
I think the biggest problem is 1 1/4" is just to narrow for a 60" cherry bow especially at 28" draw.
Your tiller may not be perfect but its not that bad either so I believe the answer is wider and longer.
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I'm kinda leaning toward what dana said....I've had a couple of bows get away from me too ;D But I did get a "fix" in that helped enough that neither one has "gone away" yet. You could try to tillerr in a little more bend on both sides of the problem area....and then even out the bow's tiller by working down the lower limb profile to match the upper.....you might loose 5 to 8 lbs but it saved my two "problem childern.
I know a lot of the fellas also add super glue to the problem areas (probably couldn't hurt) but I start all my bow finishes with 6 coats of "watered-down" lacquer (50 / 50 reduction with acetone) it soaks in real good and helps stabilize the wood cells (I think) hope you try to save it....even if it has to be a little "less stout".
half eye ;)
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The design is a problem. It is under built, apparently as I never used it, for the wood. The one glaring thing is the knot. Knt's are weak spots and therefore, should appear stiff in relation to the rest of the limb. That knot is bending too much. Jawge
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I would get started on a new bow. You can shoot it in the meantime but I might not take it to the club shoot if you don't want to be embaresed in front of the compounders. Get you a good clean piece of seasoned osage and you will have a much better shot at a durable long lasting bow. Kenneth
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Good information from everybody so far.
As for starting a new bow, well, I've got several staves with bow outlines drawn on them, just have to get into the shop to finish them. I'll go longer and wider with the next one for sure. At the knots, I will be extra generous in width and thickness. For the record, this bow has 11 knots in it, but this knot is the only place where the back of the bow isn't raised at a knot....live and learn I guess.
However, I am curious about a repair technique.
I can re-tiller the two limbs to drop some weight and hopefully lower the stress on this spot, but is this type of a failure a good candidate for a patch job (i.e. grind out and replace a piece)?
Anyone care to offer some more repair advice?
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If you have more wood just build another bow. Don't waste your time trying to patch up that one when you could be using it to build another one. jmo....
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If that bow was mine, I'd set it in the corner and make another. You could spend as much time trying to fix it, as you would making another, with no guarantees it would even work out. You made some mistakes... learn from it and move on. I have quite a big bin of mistakes in the corner of my shop, and every once in a while when I look over there, I remember the lessons.
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I REALLY REALLY hate to say this but I agree with Dana.
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I REALLY REALLY hate to say this but I agree with Dana.
Bout time ya saw it my way ya big ol cracker :D
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I've been shooting my first bow, and it has developed a problem.
That's all I needed to know to come up with my answer to you. You only get one First Bow. What you have ain't bad, lots of our firsts never even made it to the tillering stage, much less thrown so much as a single arrow. Time to put her up on the wall with a little love and respect.
Don't give up on chokecherry, just go a little wider, leave all knots unbending, and make sure you fully respect the grain of the wood. Post pics of your next bow, too!
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I have to agree with RyanO, and Mr. Cat, an accident ready to happen.
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Okay everybody....thanks for the info. Sounds like the general consensus is that I need to build another bow... who knows when I will be able to get to it though.
I still want to retouch this one to make a shooter out of it...albeit at a low draw weight - I'll tackle that some other day.
I hate to sound like a stuck record, but I am still curious if this kind of failure, in this spot, with these circumstances is appropriate to fix with the Dean Torges method, (i.e. cut out the bad portion and replace - I don't know what else to call it).
I'm trying to learn the limits of what is okay, what is bad and what is just gray area. Thanks for tolerating me.
And I do need to tell you all that I've been looking at all the great bows you folks put out, and I'm always astounded! Surfing through the pictures and the threads really helped me to get through a few long nights this past year....thanks for that.
Cheers,
J
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I've used Dean's scalloped belly patches to repair chrysals and hinges before. You've got to make them right for them to work. (I learned the hard way.) They need to taper gentley into the limbs. If the taper is too abrupt, the patch will be prone to lifting, starting at either end of the patch. Also, use Urac to glue them in and only use a VERY light clamping pressure, just the minimum to hold it in place. I got that tip straight from Dean. These things don't seem to work as well with a razor thin Urac glue line.
In any case, that chrysal looks bad. It's deep and right at a bad knot. I don't know that a belly patch would save it. Especially since there are alot of other crysals forming, I'd hang it up or if you can stomach it, just use it for kindling. I'm not big on dicey fixes or just shooting bows till they blow up. (I can't believe people actually do the latter. I have an aversion to loud bangs in my face, painful smacks, and spilling blood.)
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Actually, destruction testing can be a useful tool, it will let you feel just how much that wood can take. sometimes it's a surprise.
whenever I try something new I use the 'bad' staves I have lying around...it's impressive how much abuse some of 'em can take.
It all helps give you the feel and eye you need to make bows... or 'experience' as it's sometimes called.
I rawhide backed my 1hr bow and pulled the darned thing back to 28"...it didn't break...that taught me a lot more than pussy footing about at 26" and treting it with kid gloves.
Del
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It sounds to me like you are attached to this bow, and really want to save it and I say go for it! The choice is pretty much up to you, and I don't know anything about the Dean Torges method or how well it might work. Myself, I would squirt layer after layer of Tightbond II or III into the knot and then wrap with real sinew, and do a wrap on the other limb in the exact same spot just so it's symmetrical and the compounders won't notice it and laugh at the repair. You can even paint over it so that it looks more like a design than a repair. Nobody but you and us will ever know.
But the thing you absolutely MUST do is as Destructo first said, retiller the bow. You will need to scape (or sand) some off the bottom limb to weaken it just a tad bit, and then start about an inch above the knot in question on the top limb and reduce from there out so that the limb bends more. The bow ain't gonna last forever, but no wood bow does. But I say by all means, patch it however you like. You will gain the experience and extend the shooting life of the bow, at least a while.
CP
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Thanks again to all for the good advice. Yes, I'm really attached to this bow. Mainly because it is my first, but also because I think it was a very hard stave to cut my teeth on.
El_D and Cacatch are right, it's amazing how much out of tiller that bow looks after the fret occurred. The tiller was previously spot on, but that fret really caused some havoc.
I'm going to put this one on the wall for now, I'll fix some time in the future when I feel I understand more about repairs, etc.....as JW_Halvorsen said,"you only get one first bow"...and I'd hate to wreck it in ignorance.
I've already started on a new bow. I'll post some pics and get your thoughts as I move along in the tillering process.
Cheers,
J
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Good Luck...and Smart Move...because you do only get one....First Bow...... ;)
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You could try gluing on a rawhide patch right over the chrysals. Seriously, do tiller knots to not bend as much as the rest of the limb. :) Jawge
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take a trip to BC and get some yew
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as JW_Halvorsen said,"you only get one first bow"...and I'd hate to wreck it in ignorance.
My first bow developed a crack across the upper limb, slight lifting of grain, could possibly be repaired by superglue and sinew backing the bow. But I have left it like this for the last 6 years because if it didn't work then it would look worse and I'd know that I had really killed the poor thing. No, she is on the first peg on my bow rack and will for always hold that special place.
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definately a black eye waiting to happen. i'm all for other people experimenting with different woods but this is one of the main reasons i use osage. it may cost a little more but worth it in the long run.