Primitive Archer

Main Discussion Area => Bows => Topic started by: simson on December 16, 2017, 10:59:34 am

Title: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: simson on December 16, 2017, 10:59:34 am
This bow is made out of a unique stave. The back is along almost the entire length homogenous concave. This is enormous mass saving, but tillering is a bit more complicated.

The belly ridge comes out of the fades and ends with the tips. Cross section is more or less a 5edge with a concave base (back) and tapers at the last inches into a V-shape.

The bow is very light by mass and I think it would be a good candidate for flight shooting too. I’m curious about the calculation with Steve’s mass theory.

One minor crack at one side of the upper limb (probably a wind check) was filled with thin super glue – no problem.

The bow seems to be stiff handled, but it isn’t. There is a very little gentle bending in the handle and the built up is therefore done with three layers of sole leather. Another piece of leather glued onto the back made the handle deep enough for a comfort grip.

The handle is wrapped with black leather lacing and linen yarn.

Black buffalo tip overlays.

The back is darkened with osage soup for a two tone appearance.

I like this bow very much and hope the new owner also.

49#/28”

ntn: 57”

bh: 5Ό”

max w: 2”

mass: 428 grams

asymetric

bendy handle (very, very little)

08”: 07,0

10”: 12,2 (+ 5,2)

12”: 16,8 (+ 4,6)

14”: 20,9 (+ 4,1)

16”: 25,0 (+ 4,1)

18”: 29,1 (+ 4,1)

20”: 33,0 (+ 3,9)

22”: 36,8 (+ 3,8)

24”: 41,0 (+ 4,2)

26”: 44,6 (+ 4,6)

28”: 49,3 (+ 4,7)


(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-1-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-2-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-3-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-4-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-5-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-6-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-7-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-8-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-9-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-10-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-11-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-12-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-13-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-14-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-15-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-16-von-17.jpg)

(http://primitive-bows.com/wp-content/uploads/2017/12/osage-concave-back-5curve-4-17-von-17.jpg)

 
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: DC on December 16, 2017, 11:29:22 am
Ah, inspiration! I have a stave just like this with concave back. I've been unsure what to do with it. Now I know :D
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: bjrogg on December 16, 2017, 12:01:45 pm
Oh those are some nice curves
Bjrogg
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: ohma2 on December 16, 2017, 12:09:39 pm
Beautifull
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: osage outlaw on December 16, 2017, 01:23:12 pm
Those concave backs are a pain to chase a ring on.  Great job on that bow.
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: mullet on December 16, 2017, 04:13:54 pm
Dang, Dude, you're a machine this month. :BB :BB :BB :BB ;D
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: Pat B on December 16, 2017, 07:53:13 pm
Fun to tiller too, Clint.
 Another nice one Simon.   :OK
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: Yard Dog on December 16, 2017, 09:08:38 pm
Sweet !!!!
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: simson on December 16, 2017, 11:36:34 pm
Thanks guys!
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: Badger on December 17, 2017, 12:26:06 am
   Nice job Simpson, your bows are always on the light side but still within reason. I think this bow worked out at about 580 grams
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: jeffp51 on December 17, 2017, 12:30:11 am
This is almost the inverse of the HLD bows that we have seen lately.  I love it.
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: Parnell on December 18, 2017, 06:58:37 am
Its a study unto itself to just grasp what your doing with cross sections over the length of your bows, Simon.  The handle wrap is very handsome on this bow.  Well done.
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: leonwood on December 18, 2017, 07:19:39 am
This is really a one of a kind if you ask me, that back looks so smooth! Amazing!
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: simson on December 18, 2017, 10:34:15 am
Its a study unto itself to just grasp what your doing with cross sections over the length of your bows, Simon.  The handle wrap is very handsome on this bow.  Well done.

Steve, in my eyes more or less every design has been prooved and we've learned how to do the right length, the right front profile, the right side profile. But, there is still a wide range what we can experiment in tapering into different cross sections from fade to limbs to tips.

@jeffp51: a concave back is seriously limb saving mass - that's good, but is not an inverse HLD because here the cross section get work to do.
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: Marc St Louis on December 18, 2017, 11:59:27 am
Very nice bow Simson
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: Hans H on December 18, 2017, 12:07:30 pm
TOP! perfect in all aspects
Hans
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: Hamish on December 18, 2017, 04:51:18 pm
Holy crap Simon! You make great bows indeed.
Title: Re: Osage 5curve with a concave back 49#/28” part I (No. 97)
Post by: selfbow joe on December 18, 2017, 06:58:23 pm
Awesome looking bow