Help me with Flat Bow Dimensions

[Okie]

Alright it's time to try something a little different. I've built a couple of board bows and 8 Osage longbows and I want to build an Osage flat bow now. It probably won't get started until after the new year rolls in but I'd like to get some ideas on a lay out.
Here's what I'm thinking.
62"N2N, 4" handle/1-1/2" thick, 1-1/2" fades, Limbs- 1-1/2" @ fades up to 10" from tips then tapering to 1/2" tips.
Does this sound right?
How thick do I start the limbs at for a 60# bow?

Thanks for any help.

John

[1/2primitive]

Sounds good. Osage was made for flat bows . You might not need the full 1-1/2" width, but I would play it safe, and narrow it if needed.
Also, if you're looking for a 28" draw length, you could make it at about 66" long for saftey. If, however, you want it shorter, I completely understand (me being the short bow advocate that I am ).
As for the thickness, just take it down to where it starts bending with a floor tiller, then go from there.

And... show some pictures when you're done.
      Sean

[Jbell]

What is your draw length? That may also determine your dimensions. You could narrow your limbs a bit it you would like, down to about 1-1/4 at the most for 62" unless your draw length is really long. Will you be adding any reflex? With 2-3" of reflex I usually start the floor tillering process at about 3/8" limb thickness at the edge, but the center of the  belly will be a bit thicker with my bows since I use a slightly round belly. But really this all depends on how much reflex you add if any. If I were building a straight limb bow I would probably start with about 5/8".  You can also just slowly remove wood until the limbs begin to bend.
Good luck and keep us posted.
 Justin

[Pat B]

For a 28" draw the 62" is OK. Like Sean and Justin I would go about 1 1/4" at the fades but I would begin the taper there and go to 3/8" tips, maybe go out 3 or 4" before tapering to the tips if you want a stiffer handle area. I like my limbs bending right to the handle.
   Like Sean, I go to floor tiller stage and work from there. 64" or 66" are good lengths for 28" and would be a safer start. I've been building 62" to 64" bows for myself with a 26" draw.
   If you have the stave handy and the backed is chased, you could cut out the shape of your bow and between now and the new year you may need a little "away" time so you sneak out to the shop and do a little scraping.

[Badger]

Something I do on osage a lot or any wood for that matter is to find a single ring on the belly, right down the center of the belly as I round mine just a bit, this will get you properly oriented, then I just start removing the rings till I get a bit of flex, at that point I start to slow down and watch the tiller, 90% of the time depending on the thickess of your rings you will have a couple of V's form in the grain line that point right toward the tip. To me it goes faster when starting from one ring. Steve

[Pappy]

John that is about what I use,but I do tend to overbuild a bit.
   Pappy

[GregB]

Those dimensions sound good to me other then agreeing with Pat that narrower tips are preferable. You'd be surprised how narrow and small tips can get and still handle the stress...ought to see some of Sawfiler's bows...

[Okie]

Thanks guys. These are just for starting dimensions. I am wanting a little wider bow. I will be tillering it to 26" for me. I am really just curious about trimming the belly thickness as the bows I've been building have all been rounded belly bows that I cut faucets in. I am planning to attempt to recurve the limbs. Steam or dry heat? I have cracked a bow before with dry heat so I'm thinking steam for the recurves.
Agian thanks for the help.


John

[sulphur]

if your looking for the real flat bow look (which is so cool looking imho) wider limbs will allow a flater profile.  1 have used 1 5/8" then then taper to 3/8 tips starting anywhere from 2"-8" out from the fades.   that should get you a 62" ntn bow easliy enough.