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Main Boards => The Bowyer's Bench => Topic started by: Goose Gossett on July 24, 2010, 10:20:00 PM

Title: Osage selfbow layout question
Post by: Goose Gossett on July 24, 2010, 10:20:00 PM
So here's my question here was some bug damage that I was able to scrape down to this.  The little pencil mark is the middle and there is a hairline fracture that is tough to see above the 2 others.
(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0582.jpg)
(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0594.jpg)
I did notice that there are some cracks from the original bug damage with the last crack 1 3/4" from the left side.  Here are the knots and the knot closer to the riser and the second knot are on the side without the cracks or clean wood.  Can I angle the bow around the last 2 knots and leave the knot next to the riser or would it be better to follow the wood and include them all but the last little one?  
(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0595.jpg)
(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0597.jpg)

(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0599.jpg)
I'm still new to this and I'm enjoying the process.  Suggestions would be great!
Title: Re: Osage selfbow layout question
Post by: walkabout on July 24, 2010, 10:33:00 PM
i would try to find a grain line that would snake around the larger knot near the middle, although you may not find one. if not then still find a grain line for center that will let you incorporate the knot. if you can avoid the knot itll make for great character in the bow. depends on how wide the stave is too, if you can manage to avoid the knot and still get 1 3/4"  wide you should be good.
Title: Re: Osage selfbow layout question
Post by: Goose Gossett on July 24, 2010, 10:56:00 PM
Ahh yes dimensions... 70" long 1 3/4" at the widest from the cracks and 3 1/2" at both ends.
Title: Re: Osage selfbow layout question
Post by: walkabout on July 24, 2010, 11:12:00 PM
im guessing you could find a grain line that would get around at least one of the knots with those dimensions. just find a line that starts at a prefered side on one end, then moves arouynd tha knots to center and back to the other end. the little knot on the end isnt too bad you may end up avoiding it too depending on your layout\\design
Title: Re: Osage selfbow layout question
Post by: Goose Gossett on July 25, 2010, 06:15:00 PM
I tried my best to find a bow away from the cracks in the stave.  This was the best I could do with what I have.  Do you think the little crack near the fade will have an effect?  (I plan on super gluing and possibly hemp chord wrap)

(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0603.jpg)

I drew up what I thought would be a good outline.  Tried to follow the 2 knots on the right side the best I could.  Would they be potential problems where they are on the limb?  Planning on a 70" bow with these dimensions 1 1/2" wide til the taper at the tips with the tips being 3/4" allowing room for thinning later.

(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0605.jpg)
(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0604.jpg)
(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0601.jpg)
(http://i803.photobucket.com/albums/yy316/goosegossett14/IMG_0602.jpg)
Title: Re: Osage selfbow layout question
Post by: John Scifres on July 25, 2010, 06:30:00 PM
Why so long?  I would go shorter.  Cut it off an inch outside that knot and make it 64".  Any osage bow I've made over 66" really was a hand shocker.  That knot at the end will make the mass even greater out there.
Title: Re: Osage selfbow layout question
Post by: Goose Gossett on July 25, 2010, 06:52:00 PM
The marks on the end of the right limb are 3 1/2" apart. The knot is between 11-12" from the end of the limb.  If I took it off the bow would be 59" from the end of the knot.  I can go around it without staying in the grain lines but I hear that is a no no...  Thanks for the input so far guys.
Title: Re: Osage selfbow layout question
Post by: Art B on July 25, 2010, 07:36:00 PM
You can cut that thing in half and splice back together. Do a 180 with that knotty end and get 'er back near the handle. That would still leave you with a 64" ntn bow. I would much rather deal with that smaller knot out near the tip.

Listen to what John has to say about your intended length. Anything longer that 66" with osage and you need to stiffen the outer third of your limbs and keep tip weight to a minimum or they will rattle you teeth. ART
Title: Re: Osage selfbow layout question
Post by: walkabout on July 25, 2010, 07:52:00 PM
john and art both bring up good points as far as the length and dealing with the knots. i personally cant pull off a splice very well with my bandsaw so i never try it with good wood.lol. but if you can get it right it is definitely an option.
Title: Re: Osage selfbow layout question
Post by: Goose Gossett on July 25, 2010, 08:04:00 PM
If a bandsaw isn't an option?  Don't have one at the moment.  

Handshock on the length noted.  I'll see what I can't come up with if I were to splice it but that is totally new ground for me.  I guess there always has to be a first.
Title: Re: Osage selfbow layout question
Post by: walkabout on July 25, 2010, 08:16:00 PM
yea without a bandsaw splicing would be hard to do.
Title: Re: Osage selfbow layout question
Post by: Stiks-n-Strings on July 25, 2010, 08:40:00 PM
Should be a fine bow in that piece of wood. don't cut your handle area out yet you may need it later to get the string tracking good and leave your tips a little wide to start for the same reason. you can narrow them down last and get your handle shaped after you get it tillered.

John makes a sweet bow so I would take all the advice he and others have here and glean from it.
Title: Re: Osage selfbow layout question
Post by: Goose Gossett on July 25, 2010, 08:49:00 PM
So I can go across the grain on my growth ring around those knots and heat bend it back?  I've heard that you don't do that and I'm waiting til I'm as certain as possible before cutting in.  

If so, I'm not afraid to leave the first knot and cut around the second and leave the 3rd completely off by following clean wood.
Title: Re: Osage selfbow layout question
Post by: John Scifres on July 26, 2010, 09:16:00 AM
This is tough to do with just a pic on the internet but if it were me, I'd shift the whole layout so that big knot in the working section is in the handle.  Then I'd figure out a way to get around those knots at the tip.  As long as the area isn't bending, you have some leeway in crossing hte grain.  The last 6" or so of the bow tip shouldn't bend much at all.
Title: Re: Osage selfbow layout question
Post by: Art B on July 26, 2010, 09:47:00 AM
Like John said, try shifting your layout.

Personally, I would shift the lay-out to the wide side of that big knot. First I would square up the edge of the stave opposite that big knot and then measure to see if there's enough width for the limb at that area. You can probably get by with 7/8-1".  Even less width there with a shorter design.

Maybe I missed it somewhere, but what is your draw length and desired bow weight that you're after. ART
Title: Re: Osage selfbow layout question
Post by: Goose Gossett on July 26, 2010, 10:52:00 AM
28" draw and 50-55lbs
Title: Re: Osage selfbow layout question
Post by: Art B on July 26, 2010, 12:04:00 PM
It's pretty easy to achieve those numbers with a semi-pryamid design using osage Goose. Starting with a 1 1/4" width at fades, tapered to 1" width at mid-limb and then 1/2" width at tip.

Belly taper from fade to tip is about 1/8" difference. For example: 5/8" at fades, 9/16" mid-limb and 1/2" thickness at tips.

These numbers are close for an osage bow of around 64" ntn for the way I build my bows. For anything longer just add a little limb thickness and I think you'll be close for your needs.