Primitive Archer

Main Discussion Area => Arrows => Topic started by: WhistlingBadger on October 26, 2019, 01:02:09 pm

Title: Does compression straightening affect spine?
Post by: WhistlingBadger on October 26, 2019, 01:02:09 pm
Subject line says it, pretty much.  My chosen method of straightening a stubborn shaft is to roll it on a table until the high part of the warp is on top, then rub it a few times with a bottle, mason jar, or smooth stone.  This takes bends out of POC like a dream, and it works pretty well on sitka too.  My understanding is that it compresses the top, longer fibers (a lot like what a sinew backing does on a bow), pulling the shaft into alignment.

Since I'm all into tuning at the moment, I'm wondering if this technique affects the spine at all.  My guess (and hope) is no, since you still have the same amount of fiber.  Anybody with a spine tester ever done a before-and-after?  If so I'd be interested.
Thomas

p.s.  I'm really going to have to just suck it up and buy or make a spine tester, at some point...
Title: Re: Does compression straightening affect spine?
Post by: DC on October 26, 2019, 01:31:30 pm
They are really easy to make. Get to it. I made mine from junk around the shop. But I do have a lot of junk ;D ;D Start with this http://bambooarrow.com/dialface.gif
Title: Re: Does compression straightening affect spine?
Post by: Pat B on October 26, 2019, 04:28:14 pm
It may affect the spine on the compressed side but depending on the orientation of the compression side it may not matter. If possible you want the stiff side of the arrow against the bow and secondarily against the shelf or at least the under side.
Title: Re: Does compression straightening affect spine?
Post by: WhistlingBadger on October 26, 2019, 05:04:34 pm
Makes sense, thanks.  DC, yep, yep, yep.  I need yet another project for this winter to keep me busy until I get my deer hide back, whack a coyote or two, and can start sewing a new quiver...  (lol)
Title: Re: Does compression straightening affect spine?
Post by: Woodely on October 26, 2019, 05:21:25 pm
That's the problem with organic material,  the stiffness is never the same 360dg. and varies from shaft to shaft.   Even if you are the best Archer arrows with variance can affect the grouping. 
Title: Re: Does compression straightening affect spine?
Post by: WhistlingBadger on October 26, 2019, 05:24:16 pm
That's the problem with organic material,  the stiffness is never the same 360dg. and varies from shaft to shaft.   Even if you are the best Archer arrows with variance can affect the grouping.

Well, good.  Always good to have something to blame when I miss.   (lol)
Title: Re: Does compression straightening affect spine?
Post by: Strelets on October 27, 2019, 12:56:55 pm
I use either ash or tulipwood (American poplar) for arrow shafts. I straighten them by heating over a gas flame and bending over the base of my thumb, then laying them on a flat surface while they cool. I have measured the stiffness before and after this process. It does not affect the spine, at least not within the limits of accuracy of measurement. And yes, you do have to mark the shaft so that you measure on the same axis each time.
Title: Re: Does compression straightening affect spine?
Post by: TSA on October 29, 2019, 02:50:53 pm
we use a compression straightener to do all of our shafts, but it has a concave surface that matches the diameter of the shaft- prevents any flat spots on the finished shaft.
Title: Re: Does compression straightening affect spine?
Post by: WhistlingBadger on October 29, 2019, 04:04:48 pm
we use a compression straightener to do all of our shafts, but it has a concave surface that matches the diameter of the shaft- prevents any flat spots on the finished shaft.
Good idea.  I'm not sure if it matters to flight, but if nothing else it would look a lot better. 

Edit:  By the way, is this Wayne or Neil?  I'm about to place an order from you guys!  :)
Title: Re: Does compression straightening affect spine?
Post by: TSA on November 01, 2019, 09:43:19 pm
hi
 this is wayne ;D
Neil works for us as admin and order processing, the idea is to give me more time to design and build all the machinery this industry is so hungry for! (f) and keep the shop crew in good stead!

you can get a good roller straightener from  ace broadheads, its all aluminum, and i find the groove a tad shallow, but its a very good little unit
one other project we have been working on is, commercializing  our straightener,
 we already make our own, with yew wood handles ( warmer and prettier), but need to make a bunch for inquiries we keep getting.
this may inspire me to finish up the parts for a batch ;D.
Title: Re: Does compression straightening affect spine?
Post by: Hawkdancer on November 01, 2019, 11:11:21 pm
Put my order in for the first run!  Glad to see you survived the modifications to the operation!
Hawkdancer
Title: Re: Does compression straightening affect spine?
Post by: WhistlingBadger on November 02, 2019, 08:46:34 am
hi
 this is wayne ;D
Neil works for us as admin and order processing, the idea is to give me more time to design and build all the machinery this industry is so hungry for! (f) and keep the shop crew in good stead!

you can get a good roller straightener from  ace broadheads, its all aluminum, and i find the groove a tad shallow, but its a very good little unit
one other project we have been working on is, commercializing  our straightener,
 we already make our own, with yew wood handles ( warmer and prettier), but need to make a bunch for inquiries we keep getting.
this may inspire me to finish up the parts for a batch ;D.

Hi, Wayne.  Sign me up along with Jerry!  Feel free to shoot me a prototype along with my sitka shafts, if you must.  ha ha  I've thought about the Ace straightener; it seems a little pricey for a job that can be cone with a glass jar or a smooth rock...that, and I'm an incredibly cheap person.  Blame my Scottish ancestry...
Title: Re: Does compression straightening affect spine?
Post by: Hawkdancer on November 02, 2019, 10:24:43 pm
Wayne,
Pm sent?
Jerry
Title: Re: Does compression straightening affect spine?
Post by: Deerhunter21 on November 02, 2019, 10:32:46 pm
How do the rollers work?
Title: Re: Does compression straightening affect spine?
Post by: TSA on November 02, 2019, 11:28:37 pm
certainly for coniferous tree shafts, for hardwoods heat first then use the roller or other preferred method
https://www.youtube.com/watch?v=ofhYWRX2KlE
Title: Re: Does compression straightening affect spine?
Post by: Hawkdancer on November 03, 2019, 10:43:39 am
Wayne,
Your inbox is full, cleaning time!
Jerry
Title: Re: Does compression straightening affect spine?
Post by: TSA on November 03, 2019, 02:16:20 pm
thanks mate,
 i did clean out a pile yesterday- but obviously not enough, i find it really hard to discard meaningful correspondences i have had with folk (=)
Title: Re: Does compression straightening affect spine?
Post by: Hawkdancer on November 03, 2019, 10:31:43 pm
You are a popular chap!  My pm was was a bit in jest, anyway! >:D (lol)
Hawkdancer
Title: Re: Does compression straightening affect spine?
Post by: TSA on November 04, 2019, 01:39:56 pm
no offence taken mate ;D
i appreciate the heads up, always.
i think all of us trad/primitive archers are quite sentimental at heart- hence our preferred pursuit, and i like to hold onto the nice conversations i have had in the past, often like to go back and read them again, see how i have changed my ideas on somethings, and not on others >:D

i need to find a way to copy them into another file on this dang 'puter thing, so i can clear the box for new and interesting conversations!
i need to get my 17 yr old daughter to give me a hand with that i guess!!!
Title: Re: Does compression straightening affect spine?
Post by: Hawkdancer on November 04, 2019, 10:54:37 pm
That might be a "copy & paste" maneuver, but I'm not a wiz at this stuff, either!  I'm lucky to post pictures via  Imgur (lol)!
Jerry
Title: Re: Does compression straightening affect spine?
Post by: Todd Mathis on November 07, 2019, 03:59:28 am
Makes sense, thanks.  DC, yep, yep, yep.  I need yet another project for this winter to keep me busy until I get my deer hide back, whack a coyote or two, and can start sewing a new quiver...  (lol)
hahahahaha!   Don't we all!   I hope some of this shows up at OJAM so I can see it for real.  Great share.  Thanks.
Title: Re: Does compression straightening affect spine?
Post by: WhistlingBadger on November 07, 2019, 08:04:13 am
hahahahaha!   Don't we all!   I hope some of this shows up at OJAM so I can see it for real.  Great share.  Thanks.

I had to look up OJAM.  You know, I hardly ever wish I lived back east...but stuff like that almost makes me with.  That looks really run.  There are a couple of other guys I've run into recently who shoot trad bows, but nothing like that.  I'm grateful for this forum--it's good not to be trying to figure this stuff out totally on my own anymore.