Primitive Archer
Main Discussion Area => Bows => Topic started by: Muina on May 13, 2010, 02:21:09 pm
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I've just finished an Ash backed Ash R/D bow, finished tillering, put 6 coats of danish oil on and I noticed a tiny chrysal line running across a knot that I didn't see before. I thought it looked small enough to just sand out and it wouldn't change the tiller at all or pose any great threat to the bow. But I've just taken it out for a couple of final shots (I'm supposed to be selling this to my friend) and the chrysal's basically grown into a fully blown fracture.
I'm really worried that the bow might break any time soon, and I may have to start from scratch (I know it doesn't sound like much work but I'm doing a technical theatre course at college and we're just coming into show time so I'm going to be seriously busy).
Does anyone know of any ways to "cure" chrysals or think it won't pose much of a threat to breaking the bow?
(http://i230.photobucket.com/albums/ee155/Muina/GEDC0015.jpg)
(http://i230.photobucket.com/albums/ee155/Muina/GEDC0012.jpg)
(http://i230.photobucket.com/albums/ee155/Muina/GEDC0014.jpg)
Thankyou for any help
Anthony
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Oh yea, forgot the specs:
65# @ 28"
65" n2n
16.5mm thick and 29mm wide at the chrysal
Quite a decent tiller, maybe bending a little bit more on the outer limbs but not really bending much at all at the chrysal
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That looks pretty bad. You can do a patch with wood. You have to cut out the section. You have to fit in the piece. I' ve never done that.
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That's what I hate about Locust...it loves to chrysal....but I have never had trouble with Ash....especially a quarter-sawn Board....abut I am with Jawge....looks wicked.....I sure would not sell it to anyone....JMO....
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I think once you have chrysals the bow is just going to loose cast and get more and more sluggish.
Sanding 'em out doesn't help (yeah, I've tried) as you are removing some of the compressed supporting wood...you're just inviting more wood to compress, unless you remove a whole layer deeper than the chrysal and put a new belly on it (or turn it into a kids bow, which I did with a chrysalled Elm ELB)
My 'one hour bow' with a rawhide back chrysalled real bad, it shot great for a while but started to get more and more puddingy. (I did abuse it hugely to see what it would do).
Del
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Are they all over the limb. I think I see some others. Chrysals that are localized means that the tiller is bad. It's bending too much in that one spot. Chrysals that are spread out over the length of the limb mean the design is inadequate (too narrow, too short). I've put on rawhide patches. Never did a rawhide patch. I think I've built 7 ash bows and all but 2 chrysaled. Jawge
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Just checked over the limb and there aren't any other chrysals, I think it's just because it's right on a knot as the tiller's pretty much spot on and hasn't changed since the chrysal got worse.
I think I'll keep this one for myself and just cut a new belly for it, and start from scratch for my friend (I'm really not having much luck lately, about the past 8 bows have had something seriously wrong with them!)
Thanks for all your help guys
Anthony
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Just checked over the limb and there aren't any other chrysals, I think it's just because it's right on a knot as the tiller's pretty much spot on and hasn't changed since the chrysal got worse.
Anthony
Yes, you are absolutely right there the knot is the trigger.
If you have a piece of the ash left without any knots ;) you can repair the bow in a couple of minutes.
You only need a rasp , or a bandsaw a bit of epoxy and some linen or hemp + a piece of good wood.
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Wider. Yes, I say a little wider for knotted areas. When tillered they need to be left a bit stiff if possible I know hard to do with the small ones. Jawge
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From my experience, osage is always less likely to dissapoint. I have had poor luck with hickory. Good luck. kenneth
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Thanks so much, I'll give that a try this afternoon, I don't have any hemp but I do have a little bit of deer sinew if that'd work?
Would you have to leave that area almost completely stiff in case it popped out or is it ok to tiller it like usual?
Thanks again
Anthony
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You can tiller it like normal,the piece you glue in needs to be thin enough to bend some ,right off the bat or it will pop off just like a handle dose if the bow bends in the middle. Deer sinew will be fine. I have fixed several with a patch like that. It was probably bending just a little more in that area.Like others have said I will leave an area around knots a bit wider and have them bend a little less, sometime the tiller is a bit off but they will shoot fine,You are dealing with wood not Glass
so you need to take what it gives you. Good luck. :)
Pappy
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Thanks for the advice :)
On the sublect of starting again, do you think Titebond III will stand up to the design and weight? I used West System Epoxy last time and I grooved the laminates a little too deep (first time Epoxier :P) so I'd rather use Titebond this time.
Thanks
Anthony
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That's why I don't sell many bows, to many problems to worry about. Sorry yours developed them.
VB