Birch bow attempt

[paulc]

Anyone have any advice, other than don't use birch :-)  This is my first attempt-using the worst stave to learn on.  Pretty sure it is destined for the burn pile but maybe not.  It is pretty straight but it definitely have a good bit of prop twist in one limb.  If I were to try to steam out the twist would I steam the entire limb, or just the area where the most of the twist is located..?  And with all that is going on in that one limb not I am not use I should even try.  Stave is close to 70" long currently, about 1.5" wide and about .75" think most of the limb length.

Any thoughts?  Thanks, Paul

[Pat B]

Keep it long and as wide as possible the full width then taper the last 6" to 8" from the tips. Heat treat is well before you go too far into the tillering process.

[willie]

I dont bother to split birch. sawing seems to work.

keeping a uniform  thickness while trying to take the twist out seems like a good idea. maybe reduce some from the 3/4 i,f you can,  before steaming the limb

if you want you can steam more than just the local area . It's hard to tell from your pics just where the twist needs fixing.

the pipe wrench with a weight thing works while steaming too.

[paulc]

Not sure these pics show you anything useful....where I see the need for steam bending is right on the knots so worried the wood won't handle the stress of steamed corrections and then bending....thoughts?
Just go for it..?

Paul

[zoomer]

It's not too much twist. You can leave it with no problem. But if you want to correct it, it's better to do it during heat treating. Steam is more suitable for more severe bends, dry heat for mild bends. Remember to untwist further than needed, as it will twist back some.

[paulc]

Here I am so far with the birch stave...i have no idea how to handle the limb that is wavy.  I heat treated the belly, tillered, heat treated again and tillered again.  I did my 3rd heat treat yesterday and will try tillering more later.  The left limb is easy as it is nice and straight, my gizmo works well to show me if I have an even bend.  I don't think I can use the gizmo on the right limb as there is a wave or dip every 8 inches or so.  I have taken to trying to watch closely while pulling the tiller sting to try and tell where the limb is bending...

maybe a little bit of set, but only a tiny bit...

Thoughts?  Thanks, Paul

[willie]

yes, birch like to be wavy. How come the trees look so straight?

you mention "third heat treat". are you heat treating the belly or just using heat to straighten the limb.?
trying to take out the waviness?

DC mentioned a method he used that I want to try next time on birch.  he has a backdrop behind the tiller tree he can trace out a series of lines on for various draw length profiles.I think he uses a bow of similar profile but with smooth straight limbs.

[Del the cat]

I reckon you'll be ok as long as you don't get too ambitious with the draw weight/draw length. 20# @ 6" you'll be fine 
Del

[paulc]

Heat treat is to try and keep weight up and prevent set, not to correct limbs in any way.  It seems to not be taking set yet but I am also not drawing it very far yet.

And yes, I am hoping for a bow I could hunt with but as long as it doesn't blow up on me I will be okay with whatever comes out of it :-)  I have several more staves with which to try again....

Paul

[willie]

Heat treat is to try and keep weight up and prevent set.......as long as it doesn't blow up on me

I have been tempted to heat treat to increase weight, but use narrow crowned staves, so I have been hesitant. so far, all my birch bows have just taken set if overdrawn. Please let us know if you experience a blow-up
thanks

[loefflerchuck]

I love yellow birch. It's not the fastest, but makes a good dependible bow.