Primitive Archer

Main Discussion Area => Bows => Topic started by: osage outlaw on October 21, 2015, 11:21:37 pm

Title: Concave growth rings
Post by: osage outlaw on October 21, 2015, 11:21:37 pm
What is everyone's thoughts on concave growth rings on the back of a bow?  Does it help or hurt performance?  Should you make the belly more rounded?  I know it is a pain to chase a ring on a concave back.  I spent the majority of the day using a goose neck scraper to go down about 10 thinner rings on a stave today.  The entire back is concave from one tip to the other with a lot of pin knot clusters.   
Title: Re: Concave growth rings
Post by: Del the cat on October 22, 2015, 02:36:05 am
I love 'em, it's a nice bit of character. I like the thumb groove feel it gives.
See it quite a bit on Yew, As long as the edges are rounded I don't think it makes any difference concave convex.. whatever :laugh:
Dunno about Osage specifically, only used it twice... mind I got a bit from the giant tree tuggin' at my sleeve for some cat lovin'
Del
Title: Re: Concave growth rings
Post by: Badger on October 22, 2015, 06:32:10 am
  I have had it a few times, pain in the rear chasing rings on it. I treat the belly the same as I do on other bows, semi flat.
Title: Re: Concave growth rings
Post by: ravenbeak on October 22, 2015, 07:24:03 am
Of all the self yew bows i have seen fail,  low centre and high ridges  along the back has been a leading cause.  So,  not a big fan of concave back on a bow.  I think it puts too much stress on the corners.  Personally I would rather violate the rings to flatten the edges a bit than leave them high.   Just my experience
Title: Re: Concave growth rings
Post by: JoJoDapyro on October 22, 2015, 10:14:52 am
I am working on one that has a big knot. It goes from convex to concave to convex and back again. Not fun. I have single ringed the whole thing in about an hour, except the knot, and i'm about 3 in now, and still not done.
Title: Re: Concave growth rings
Post by: bradsmith2010 on October 22, 2015, 01:34:10 pm
i have made bows from back partially concave,, kept the taper even on tiller and had no problem ,, just as suggested very hard to chase a ring,, :)
Title: Re: Concave growth rings
Post by: bubby on October 22, 2015, 01:40:52 pm
I'd round the edges good almost trapping , not that i have done many concave backs but that would be my approach and a slightly rounded belly, that stave looked like a beast to chase too
Title: Re: Concave growth rings
Post by: missilemaster on October 22, 2015, 01:44:39 pm
flip it over and make the back the belly! ;)
Title: Re: Concave growth rings
Post by: paulsemp on October 22, 2015, 04:06:37 pm
A few times after I get the ring chased and that convex area still stands I take a little screwdriver and start tapping on the early growth and sometimes you can pop the whole thing out without damaging the other ring. I gotta really be in the mood to sit there with a gooseneck scraper and try to scrape it out
Title: Re: Concave growth rings
Post by: Drewster on October 22, 2015, 06:55:51 pm
I finished an Osage bow in the spring that had a pretty serious concave area in the back of one limb.  I patiently chased the back to one good ring and profiled the belly to follow the contour of the back.  So far, the bow has performed very well.
Title: Re: Concave growth rings
Post by: Buckeye Guy on October 22, 2015, 07:50:31 pm
If you stay centered on the rut it goes ok.
Title: Re: Concave growth rings
Post by: George Tsoukalas on October 22, 2015, 09:17:28 pm
I have not noticed any difference. A rounded shavehook makes it easier for me to chase a ring.
http://traditionalarchery101.com/osage.html
Jawge
Title: Re: Concave growth rings
Post by: osage outlaw on October 22, 2015, 09:59:30 pm
I like to cut large diameter trees which are more likely to have concave areas than smaller trees.  I have made a few that had concave backs.  One of them seemed to be a slow shooter.  I wasn't sure if the shape of the back had anything to do with it or if it was something else.  It was kind of snakey to.  That probably had more to do with it.  Thanks for the replies. 
Title: Re: Concave growth rings
Post by: lebhuntfish on October 22, 2015, 10:11:40 pm
flip it over and make the back the belly! ;)

I'm with missilemaster!

I made on that had a narrow, almost groove like section along most of the top limb. Pain in the rear to chase. But I sinew backed it and just made it smooth!
Patrick
Title: Re: Concave growth rings
Post by: osage outlaw on October 22, 2015, 10:41:05 pm
Chasing a belly ring wouldn't work on this one.  I was trying to avoid some side checks and needed the width of the back of the stave.