sinew "bandaids"

[jayman448]

I remember reading in bowiers bible wrapping a hinge or small crack with sinew as a bandaid solution. Would it be worth it to try this on light chrisels

[IndianGuy]

Belly fractures are usually caused by putting to much pressure on the bow before it was tillered properly, black locust is the worlds worst to let you know if your tiller job is off by getting these little fractures.
A sinew wrap will not fix the problem and when you usually have one failure more are likely to appear over time. You can heat treat the belly of a bow to help harden it and this will help eliminate the problem to some degree, but once they are there you can't getting rid of them.
just my .02$ worth.
E

[bubbles]

j think the most widely accepted cure for chrysals is to start a new bow. You can use a torges patch to repair it, and i have had success with those.  Essentially cutting out the failed wood and reglueing new wood in with urac or resorcinol. 

[jayman448]

So, why would it work for patching some forms of weak spot and not others?

[wizardgoat]

Because there's no compression strength in sinew.
Are the frets in a hingy spot? Post pics it helps

[mikekeswick]

If a bow chrysals then it's been severely overstressed in this spot. The woods strength in tension was all that has stopped it from blowing. Wood is naturally weaker in compression therefore you get chrysals.
This has already happened and cannot be reversed.
So what you are left with a section of the belly that doesn't have the resistance to bending that the rest of the undamaged belly has and therefore receives a 'double whammy' of stress. It was already overstressed just before the chrysals showed up, if this weak spot had been caught earlier in the tillering process then you could have made the necessary adjustments needed to stop that section of bellywood getting damaged.....but that didn't happen so now you have this weak spot AND damaged wood at this weak spot.
Putting sinew on the back will eventually make that section of limb 'stronger' and therefore take some load of the belly BUT your bellywood is still damaged. Sinew has little stretch resistance so you will have to put lots on the 'cure' this problem.
The best fix is to start a new bow and tiller it well. Wood speaks to you as you tiller through set (however small) and will tell you that it's about to chrysal..... An actual chrysal though is like the wood giving you a smack on the back of the head.....and shouting you should have listened to me!

[George Tsoukalas]

You can try putting on a patch of rawhide over the chrysals.

There are actually 2 causes for chrysals.

First, is a tillering issue. The stave bends too much in one spot and the belly collapses. Chrysals are localized. Had plenty of these. One never knows how long a chrysalled  bow will last. I've shot one for a good year.

I have not had many BL bows chrysal but have had lots of white ash chrysal. So much so that I stopped using ash.

Second, is a design issue. Chrysals occur over most of the limb. I have not had any of these but I've seen bows that exhibit this type.

Jawge

[PatM]

Still not getting why you keep recommending rawhide as anything more than an out of sight out of mind solution.

[Marc St Louis]

The title says it all.  A bandaid covers the wound until the wound heals, not likely the wood is going to heal here.

[George Tsoukalas]

My reasoning is that the rawhide would keep the limb from bending too much in that area. Take some of the compression. I've used it. Quick and easy.
I would not waste time doing a wood patch.
Rawhide is a bandaid.
Jawge

[PatM]

Make a bow and then rawhide the whole belly and see if it provides any sort of compressive strength.

[George Tsoukalas]

Pat, what are the other choices for prolonging the inevitable failure caused by chrysals?

You can retiller leaving the chrysalled area alone and removing wood from above and below the spot? Retiller the other limb also to match. That works.

You can do a patch. Too much work.

You can do the rawhide. That works.

You can make another bow. That works too.

Whatever makes you happy.

Jawge

[PatM]

I am saying that it makes no difference. Rawhide just isn't stiff enough to take that sort of load. You might as well stick a piece of duct tape over the chrysal or a dab of paint.

[jayman448]

This is just a hipothetical question to possibky gqin a to fkt the toolbox. I was mre thinking of if you were to sinew all the way around the bow as if wrapping a bandaid around your finger (not just the back ) in hopes of stiffening that one area was my thought process. I see the majority wont bother tho. Interesting to see everybodys opinions tho 

[PatM]

Bow material needs to run  from end to end, not around.