Board Bow, RedOak - Tillering Quest'n

[Canoe]

Howdy Folks,

So, on this beautiful day, I'm pleased to be making a pile of curly wood shavings with my trusty, flat spokeshave.  One of my projects is this RedOak Board Bow; 66" Long, 1-3/4" Wide 'til mid-limb where it tapers to just under 1/2".  It's an American Longbow style bow (I think?), with a stiff handle area.  I'm shooting for about 50#@29".

Here's the question...  At what point I'm I ready to put the bowstring on? 

Currently, I'm using a "long string" that is made of a non-stretching material, the loops (the length) are tied so that I have to bend the bow some to hook the loops onto the knock groves.  (Although, once the "long string" is on the knocks, the bow isn't bent.)  With this setup, it's bending evenly, and (using my digital fish scale), I'm getting 20#@15" and 30#@20".  I'm shooting for about 50#@29".  Again, at what poundage / draw length do I string the bow to enter into the final tiller stage?

And...  With N-to-N at 65", what is my bowstring length supposed to be?

Thank you very much for you help and guidance,
Canoe

[mullet]

 If you already have it at 20". I'd increase the pull using a tight tillering string with about a 4" brace height. Pull  untill you reach your target weight and see where you are at on your draw length. If you are within an inch or two I'd string it and scrape the belly till you reach the draw length you are after. I usually make my strings 4" shorter than the N to N length.

[George Tsoukalas]

How long is the non bending handle? How long straight is the grain on the edge and back? 65" is short for a 29 in. draw. To answer the question, I long string tiller out to 10 inches making sure the limbs are bending well. I check weight all along never pulling beyond 5# over target weight. When I get target weight or 5 # over at 10 in. with the long string I string it at a very low brace 2-3 inches. As I tiller I increase the brace hight assuming all is well with the limb bending. More on my site. Jawge
http://mysite.verizon.net/georgeandjoni/

[Canoe]

Howdy George T.,

Hmmm...  It sounds like I may have taken too much off already?

"How long is the non bending handle?"
I left the limbs stiffer near the handle area so to be sure I wouldn't get it bendding too much near the fades, as I have done in the past.  If I still can, I'll be sure to get the whole limb bending so to help make up for it being too short for a 29" draw.

"How long straight is the grain on the edge and back?"
I'm pretty picky about that when selecting Red Oak boards from my local home building supply store (HD).  This board is Really nice... very straight grained on both the back and edge.  It's quarter sawn - I think.

So, at this point, I'll brace it at about 4" and see what my draw length is at 50#.  If I still can, I'll be sure to get it bending near the fades and out to about 5" from the tips.  No matter the final draw weight, I'd like to bring the draw length out to 29".  It's a gift bow for a friend, and if the draw weight is a little low, he'll use it for practice shooting.  (Or, is it just TOO short?)
I have another nice Red Oak board in the basement - ready for another attempt at a 50#@ 29".
 
What length bow (N-to-N), do you recamend for 29" draw? 
And, what about the width (1-3/4") - is that OK for a Red Oak board bow, 50#@29"?

Thank you both, George T. and Mullet for your input...  and I'll buy a 51" bow string for this bow.
Canoe

P.S.  I also have a pile of White Ash staves dried and sitting under the basement stairs... maybe I'll use one of those for this project?

[George Tsoukalas]

Evening, Canoe. I guess I would have gone high 60's ntn. The other possibility is to let the handle bend but you already glued on a piece. Just make sure the bending starts at the end of the fades and hope for the best. I'd say 27 in. is doable. Get as much bending as you can. The other thing is to consider a backing like linen, burlap or silk (in that order). I'd do that before the first stringing. I'm glad it is straight grained. Have fun. If it breaks, so what. Are you on a rope and pulley? I hope so. Jawge

[Canoe]

Howdy George T.,

Yup!!  I took too much off already.  It's now about 47#@28"

The limbs are still pretty stiff near the fades - too stiff.  On one of the limbs it's stiff a good 3"  away from the fades, and that limb has a bad string angle - stacking.

In general, I'll give it a very low grade for tiller shape ==>  hinges and flats.  (And No, I'm NOT posting a picture! 

For this one, I'll back it, and then work on getting it bending more smoothly.  I'll try to get it shootable at my 28" draw.
 
You suggested a backing - I have some silk and some of that (nasty) drywall tape (w/ F-glass)?

You also suggested a string and pulley type tillering tree.  Well, I'm big into safety.  And, if I don't follow your suggestions, then I shouldn't be asking you for help.  So, my next project will be that string and pulley setup.  I already have most of the stuff I need to build it - including a pegboard back board to use as a grid for checking limb symmetry.

Meanwhile, I'll layout my next Red Oak boardbow with a N-to-N length of about 68" or 69" for a 29" draw.  And I'll reread the tillering guide on your web site.

Thanks,
Canoe

[George Tsoukalas]

Morning, Canoe. I've never used fiberglass. I tend to stay as "natural" as possible in this 21st century. It's ok of you want to. It's good you got it to 28 inches. Probably a good idea to back it before you go for 29 inches. Don't be shy about posting. I'll guarantee you I've made every tillering mistake there is to make. Jawge