Help! Have I got chrysals??

neocaligatio

New member
My ever-so-slow attempt at a longbow (using a stave from Irondale Longbows) has hit a hurdle: Are these chrysals in the hickory backing?





If so what can I do?

Chris
 

Et-Tu-Brute

New member
Those aren't chrysals, chrysals are compression fractures which appear in the belly of the bow, not the back. They look more like lifts to me, which indicates that part of the bow is failing in tension. Personally I would bind over that area tightly with a strong thread or similar then soak the binding in glue, this has worked well for me in the past.
 

neocaligatio

New member
Thanks for the information - I'll wrap those areas once I've finished the tillering - Here's a picture showing the tiller so far and where the two 'lifts' are. The larger one above is the one near the grip, which is intended to be non-working, and the smaller is the one near the left hand tip.



The tiller needs some work too - any advice? The left limb bends much more, so I intend on scraping more from the right limb, is that sound logic?

Chris
 

TheBigTwang

New member
The one in the middle will hopefully be hidden by the handle. String and varnish or glue is a good repair. You could also use rawhide or sinew.

The one at the tip is strange, maybe due to a stiff tip. I'd try and get that side bending a touch more to even it up.

Nice combo, hope you get to shoot it.

TNT
 
Thanks for the information - I'll wrap those areas once I've finished the tillering - Here's a picture showing the tiller so far and where the two 'lifts' are. The larger one above is the one near the grip, which is intended to be non-working, and the smaller is the one near the left hand tip.



The tiller needs some work too - any advice? The left limb bends much more, so I intend on scraping more from the right limb, is that sound logic?

Chris
Hi there, it looks to me like a potential hinge is devolping in the lefthand limb, you need to get it bending with a more even arc. Eg. mark where the bend is more severe in the limb then take wood off evenly from either side of that area. Once the left hand limb is bending evenly try to balance the limbs. Yes your logic is sound! It's very important that you don't pull the bow very far whilst the limbs are uneven or hinged as this would impart to much strain on the weak areas causing these areas to take set therefore reducing the woods ability to store energy in the future = slow arrows!
My best advice is to get the Bowyer's Bible books start with the first one - make lots of bows - buy the 2nd one - make lots of bows - etc....!
By the way hope it turns out well for you!
 

neocaligatio

New member
Well I'd thought I'd taken enough wood out exactly as you described, but unfortunately I was wrong! The hinge is still there and the limb has taken on some set :(

I'm going to keep trying anyway and see what the end result is.
 

tinkerer

New member
Because your arrows mark places that are hardly bending, I would have thought it unlikely that there would be problems but binding and gluing would be a precaution.

The right hand limb shows a good tiller. Try working on it evenly and as it slowly bends more the faulty left hand limb will gradually straighten, but because it has already taken some set it may never quite catch up.

The left hand limb may be worked on closer to the handle (below the barrel)to help smooth out the bend.

Doing all this will reduce the draw weight of the bow so you may undershoot your intended poundage. The bow should also balance physically about it's centre point and working mainly on just the one limb may disturb that.

Looking at the bow again, it's nearly very good; just a bit too much taken off at the hinge. So wood has to be taken off everywhere else. You'd be wise to have the bow bending a bit closer to the handle.

David
 

mezaman

New member
the first photo looks like there is a wave or bump in the grain where the wood is starting to splinter. If the back of the bow is perfectly flat and not following the bump in the grain then the fibres will have been violated.
De-crowned wood must follow a single growth ring and all the lumps and bumps in the grain, if fibres are violated then splintering will occur.
check the whole length of hickory backing to see if grain undulations have been followed faithfully.
You could back the bow with cotton, linen, rawhide or sinew, if a single growth ring hasn't been followed then I would back the entire length of the bow.
Beware a longbow with any other backing than wood isn't a longbow as far as GNAS are concerned!
But a broken longbow is just kindling to light a fire with!
As far as tillering goes, the bow looks too flat in the handle and too whip tillered at the tips - if you want to check each limb is tillered the same amount, then check this by floor tillering. If one limb is stiffer you'll feel it against the floor.

Good Luck
 
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