Questions on how to handle reflexing tips and straightening body of bow???

[1776J]

Hello fellas.

Well, I've taken down the stave some, beginning to rough it in as can be seen in the photos below.
Of course I still have a ways to go till I get it into a closer roughed in design resembling the general design and layout.
I'm basing this on a Lakota Souix design, also an Ed Scott bow shape that I have become interested in shaping up.

I have THREE questions that I am contemplating regarding the bow....

1) 
I will need to make this a reflex/deflex bow and turn up the stiff tips *(refer to the photo of the Ed Scott bow design, looking at the tip curves)*
So, in doing this, I find myself running into a bit of a problem.  I have that knot cluster area that I have to figure out exactly how to handle.

I was examining the process at which ends are turned up via dry heat from a heat gun and was trying to judge how long the ends are from the beginning of the bend (reflex) to the end of the tips.  After looking closely
at a video online of Ed Scott bending the ends, looking at the size of his thumb placed on the stave when he bends it, it appears that this area (from start of bend to bow tip) seems to be around about 12" -13" inches?
Of course I'm using this video on youtube as a reference point for working this stave up....hence the measurements and questions.

Look at these photos of the limb area with the knot cluster,... where should I begin the bend of the reflex here?  Don't want to jeopardize the bow due to a lack of knowing how to handle this area!

**(Sorry, that should read "reflex" not "refles" in photo below!)**





2)
The bow stave has a slight twist in it and the side bend.

a)  At what point do I want to start to straighten these out? 
     Now, at this stage of having roughed it in, or later, after I have roughed it in more, more towards the tillering stage?  (or will that "twist" just come out on its own "during" tillering?)

b)  Do I want to fix both the twist AND the side bend at the SAME time, or which would I want to fix first and second?
     (Does it even matter which is fixed first?  Does it play a part in the outcome of the bow?  If so, why? How?)










3) 
At what point will I want to put in the reflex on the ends/tips?
I'm thinking earlier, rather than later.  I've seen Ed Scott do it right after roughing out the bow (thinner than what I have here of course, but still MUCH thicker than a stave worked up to the tillering stage!!)
This way I'm thinking, if there are any thin or hairline cracking that appear in the outer layer of the belly by chance, I'll just shape it down "past" that affected ring or "rings??"  to unaffected rings?

What do you fellows do when working on a bow such as this one's design?  I know there's more successful ways to do this than just one!

***(For reference,...a youtube Video of Ed Scott's working up a stave while it is still pretty thick)***

(NOTE)*** He mentions in the video that he bent this piece of wood while it was still "green" and not dried out.  To compensate for a dried piece of Osage that's been dry for about 2 yrs, (which is my stave here), would I want to still use dry heat with the heat gun, OR, try putting in some moisture bu spraying it with a spray bottle and heat it,.. or make makeshift steam box over the stove with a large pot and makeshift tent with the limb inside of it? (or any other successful idea??)

 - Link to video
http://www.youtube.com/watch?v=hgNm2TxrqFY&NR=1

The style and profile of bow that I'm looking to resemble when all is said and done. 
Bow will be 58" long, 50-55# at 27" draw length.
*(photo references below, thanks to Ed Scott)*



Thank you very much for the help in advance....
and Have a VERY Happy New Year! 

[sailordad]

looks like yor goimf for a mollie style or holmie style bow
 wait for rich aka halfeye to chime in
hes probably one of the best with that design of bow on this site
as far as beding that wood,there are many guys here much more qualiied thani to help with that
but if it was mime i would get it a little closer to floor tiller if nit completly floor tillerd
then use dry heat and a form and take the lateral bend out first
then i would work on the twist by heating and placing wedges a needed and clamp to form to counter the twist

[osage outlaw]

I remove a lot more wood before I heat straighten.  I get the limbs to about 3/4" thick and then use the heat gun.  Less wood = less time heating.

[1776J]

I remove a lot more wood before I heat straighten.  I get the limbs to about 3/4" thick and then use the heat gun.  Less wood = less time heating.

I was figuring less wood=less heating, but on the other hand,...
when do I want to put the reflex and deflex into it?
I'm thinking not to far from where I'm at now so that if I get little cracks in the belly as its bent (which I've heard and read is common) then I'll be able to take down the wood into a good ring/layer on the belly, past any hairline cracks, etc.

What's your thoughts fellas on when to put the reflex and deflex into the bow?  Like I said I'm thinking early on rather than later on??

[Pat B]

Depending on the stave but generally after floor tillering(getting each limb tip to move 4" or so with even bending limbs) and sometimes also nearer final tiller. With too much wood you have to get the wood hotter thus a better chance of checking as any residual moisture leaves. The closer you are to final shape the less heat needed and corrections are more effective.

[1776J]

Oh ok,.. thank you Pat.
I'm taking notes!  

At the point where I have it bending that much, won't it be pretty thin by then,... with a 58" stave?
Just don't want to get it to thin then  have to take off to much wood "IF" thin cracking show up on the outer ring on the belly, ya know?
Are thin cracks on the belly commonly seen after bending?
If not, why would they show up generally?

....not enough heat?....to dry, lack of needed moisture?....to tight/drastic a bend?
Are there any calculations for how tight a bend relating to the thickness of the wood being bent?  (just generally speaking, of course it all depends on the wood, or its dryness factor I'm guessing?)

Thanks!

[1776J]

?

[Pat B]

At floor tiller your bow should be way over draw weight.   Actually the thinner the wood the less chance if it cracking. Less stress on tension and compression side.   If you are heat bending a tight radius there is a chance of the belly cracking across the grain. Again, the thinner the better. Also if you take the belly down to one solid ring just like the back there is less chance of splintering.
   I really think you are over thinking the whole process and you are trying to walk before you crawl. The bow design you have choses isn't an easy design to master. Maybe you should start with a simple bow design, learn proper tillering and how wood works then when you have that figured out go for whatever design you fancy.

[1776J]

At floor tiller your bow should be way over draw weight.   Actually the thinner the wood the less chance if it cracking. Less stress on tension and compression side.   If you are heat bending a tight radius there is a chance of the belly cracking across the grain. Again, the thinner the better. Also if you take the belly down to one solid ring just like the back there is less chance of splintering.
   I really think you are over thinking the whole process and you are trying to walk before you crawl. The bow design you have choses isn't an easy design to master. Maybe you should start with a simple bow design, learn proper tillering and how wood works then when you have that figured out go for whatever design you fancy.

Actually, I "did" work on an osage piece I had here a while back (last month I had a small stave, long story,..don't ask). 
I simply didn't share it right away due to a little bit of insecurity till I got a decent ways into it before deciding to share (which I didn't at the time)
I found that learning to tiller properly wasn't very hard, (as I was hoping) however, working much to late one evening I made a blunder and had made a gouge with a rasp (don't ask me how I managed it!!??),
didn't catch it, and when I drew it back the one end snapped.  When I looked at the area I pulled a Homer Simpson (with a slap to the forehead)
So, after having read, read, and read some more on tillering, I pretty much took my time, went slow (except for that one late night) and got a nice tiller going (before that late night "oops"!)  I still had more tillering work
to do as can be seen in the photo below, but it had been coming along nicely.

I had tried with it to bend the tips, (see makeshift jig I put together) but did not actually intend to pull the tips to bend them to that actual radius, but rather used the round pvc ends to only give me a good round, solid surface to work with.
I got small cracks AND the thing is, I had already taken the bow's limbs down quite a ways,... TO MUCH as I didn't have enough wood left to work out those tiny hairlines that appeared.
Hence all my cautiousness and most likely an over-abundance of questions and as you mentioned, quite possibly a bit of "over-thinking" bending the ends.
I'd rather over think it at this stage, find I was indeed over thinking it, and learn by having my concerns turn into nothing to worry about, than not as, not over think it, and find myself with an issue of any sort. 

Here's what I had a while back (before the death of it last month) 
(Yes, it is the kitchen,... I had better luck with taking photos there instead of my work area, just better lighting,.. I'm not actually working in my kitchen though! hahaha!)



Here is the make shift jig (just something I threw together on short notice) and the cracks I saw:

[Pat B]

Those are compression fractures(frets, chrysals). They occur when wood is bent too much in one small area. The surrounding wood crushed the wood fibers at that point. It is not from the heat. It is from uneven tiller(most of the time).
 I don't understand your jig either. Why are you trying to hold your stave in deflex?

[1776J]

Why are you trying to hold your stave in deflex?

That was an error on my part when I threw that together.
I know "now" that didn't need/should have been done that way.

[1776J]

PatB,...
in making a forming buck, would I simply be well of with a piece of 2"x8" or 2x10" pine from, say my local home depot?  Thinking about an inverted "T" design for a bow forming buck.

I figured that would work out well for a form, but figured I'd out it out there first.

[Pat B]

It depends on what you plan to do. I mostly build selfbows so I use a form like this to straighten out limbs and add some reflex. It is a 2x4 cut to shape and mounted to a 2x6.


For just workin limbs and adding reflex and heat tempering I use a simple, one limb form like this...


and for putting in recurves I use one like this. I have others with more drastic recurves too

[Pat B]

I don't know where that first pic came from. Here is the form made from 2x4 screwed to 2x6..
  Whell, photobucket is screwing up. I'll post pics of that form later.

[1776J]

I don't know where that first pic came from. Here is the form made from 2x4 screwed to 2x6..
  Whell, photobucket is screwing up. I'll post pics of that form later.

Oh ok,... yeah I'll be looking forward to those photos!

On the forms you have, you just work one limb at a time then,... interesting to see how fellows work.  I've seen a few that were a two-limb form,... basically doing the whole bow at one time. 
Nice C-clams as well,.... I like the old wing-nut ones like those as well, just picked up a few real cheap at an antiques store, almost no one buys old tools around here, a + for me! 

PS.
What is that first bow backed with??  Looks pretty neat!  Zebra-like!