Primitive Archer

Main Discussion Area => Bows => Topic started by: ajbruggink on July 27, 2015, 08:46:13 pm

Title: How should I bend this limb?
Post by: ajbruggink on July 27, 2015, 08:46:13 pm

Heh guys,

I'm working on a red elm stave and it had a natural reflex in one limb and is pretty straight on the other limb. I want this to be unbacked bow, my first instinct would be to steam the straight limb and bend it to match the other limb but I'm wondering if there's a better way to do it? Can I use direct heat to accomplish this, like a heat gun? Also, I worked the limbs' thickness down to about 3/4" all along their length, the straighter limb is slightly thicker right now, should I trim the thickness so it is like 3/4" from the fade-outs, 5/8" at mid limb and 3/8" at the tip or should I let the tillering process handle that? My goal is a 55 lb bow at 28" at 66" ttt, 64" ntn, right now its length is 70", I left it this long just in case, and its limb width from flares to mid-limb is 1 3/4", where it then tapers to 1/2", I have left the handle full width for now as well. Your replies and advice are greatly appreciated.

Thanks,

Aaron

p.s. the board in the pic is only to compare straightness

Title: Re: How should I bend this limb?
Post by: Badger on July 27, 2015, 09:10:36 pm

  I never measure thickness, I just take the limb down until it floor tillers nicely. ( this is usually about 20# heavy) Then I would put in on a cawl and heat both he limbs too match.

Title: Re: How should I bend this limb?
Post by: Pat B on July 27, 2015, 10:42:57 pm

I agree with Badger.
 Check my build along in the "Archives" section, "60" Elm Static Recurve". It has quite a bit about straightening, bending and tempering elm with a heat gun and olive oil. Any veg oil will work.

Title: Re: How should I bend this limb?
Post by: bubby on July 27, 2015, 10:56:07 pm

Yeah just even them up it's not near as bad as this http://www.primitivearcher.com/smf/index.php/topic,53350.0.html

Title: Re: How should I bend this limb?
Post by: fiddler49 on July 28, 2015, 12:35:03 am

Heat gun will work fine, Just get the limbs to floor tiller thickness, around a half inch thick. I took out 5 inches of deflex on a vine maple stave. It now has a 1/2" of deflex after 500 shoots. cheers fiddler49

Title: Re: How should I bend this limb?
Post by: mikekeswick on July 28, 2015, 04:03:58 am

Personally I'd just make the bow. There is no need to have the limbs 'matched' if you don't want to. Reflexed limb would be my upper limb.

Title: Re: How should I bend this limb?
Post by: ajbruggink on July 28, 2015, 10:22:36 am

Thanks for the replies

If I took mikekeswick's advice and didn't match the limbs, what would happen? I thought about matching the limbs because I thought tillering this stave would be more difficult this way. Am I wrong? How would the bow perform without the limbs matching?

Thanks,

Aaron

Title: Re: How should I bend this limb?
Post by: bubby on July 28, 2015, 10:26:54 am

The bow will perform fine but the bow will be easier to tiller if the limbs match

Title: Re: How should I bend this limb?
Post by: ajbruggink on July 28, 2015, 10:45:29 am

Well that's a good reason to do it for me, thanks bubby.

Title: Re: How should I bend this limb?
Post by: Pat B on July 28, 2015, 11:44:49 am

It will be easier to tiller if both limbs are even but as long as both limbs bend evenly and together it really doesn't matter. You'll get the same end results.

Title: Re: How should I bend this limb?
Post by: bubby on July 28, 2015, 12:15:45 pm

Make sure you post pics 😉