Primitive Archer

Main Discussion Area => Bows => Topic started by: ShinneryOak on November 27, 2007, 07:06:41 pm

Title: Tension & Compression -Ipe vs. Osage
Post by: ShinneryOak on November 27, 2007, 07:06:41 pm
Hi, I posted a little last year but have been away a while. I am restarting a project, trying to make an Osage flatbow backed with Ipe. I remember reading that one wood was stronger in tension, the other in compression, but couldn't remember which was which. I got the idea just because I'd never seen it done but want to be somewhat  logical about it. Obviously would want the backing stronger in tension, belly stronger in compression. I might even flip-flop and try Ipe backed with Osage depending on this. Can anyone set me straight? Yeah, I know bamboo would probably be wiser but I had to be different.
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Coo-wah-chobee on November 27, 2007, 07:52:03 pm
                    Osage is stronger in tension, ipe in compression. That bein' said back ipe with osage. But why bother ? Hedge (osage) is fine by itself . Ipe can be made ta be much stronger in tension but it takes a while and ya need ta know a coupla tricks fer the wood. Rich Saffold is the "guru" of ipe so maybe he will weigh in ta the discussion.........bob
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Kegan on November 27, 2007, 07:56:08 pm
Bamboo backed ipe is a legendary combination. Strong, fast, and with minimal set. Osage might be too dense for a backing, but that's just me ???.
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: D. Tiller on November 27, 2007, 08:53:07 pm
Hickory backed Ipe and Osage are wonderfull!
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Coo-wah-chobee on November 27, 2007, 10:07:31 pm
...Why would anybody back osage, except ifn ya want somethin' ta do ! ???.....bob
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: mullet on November 27, 2007, 10:17:00 pm
  I've got a R/D bamboo backed osage almost tillered that will show somebody why backing 'sage is nice.I think it is going to scream. :)
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Coo-wah-chobee on November 27, 2007, 10:23:30 pm
 Hey Eddie, I hope it does scream ! So what ? Ya kno' what I am gettin' at ! ;)......bob
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: adb on November 28, 2007, 04:11:26 pm
Hi,
In my opinion, osage and ipe are both belly woods... excelling in compression. Never heard of an ipe backed anything. Osage is just fine on it's own, but if you have a marginal piece, you can back it with bamboo or hickory. I think Dean Toges may disagree on why you'd back osage.
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: D. Tiller on November 28, 2007, 06:29:02 pm
Ossage is a fantastic wood for shorter bows. But, the denisity makes it a problem for longer bows like English Longbows up to arround 90# but beyond that its still fantastic. If you back ossage with Hickory from 35# to 90# the bow turns into a real slinger and tosses them with authority and speed where ass an unbacked ossage of 74" pluss would be slower. Nice thing about this combination, from what Pip Bikerstaff has mentioned, is that it will take a small set and then seem to actually pick up speed after getting worked in. It also makes a bow that will last a very long time!
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Rich Saffold on November 28, 2007, 09:56:38 pm
S Oak, Like mentioned the bamboo is good on either woods, and either wood makes a good selfbow. It easier to do with osage in our continent, and I'm sure the Amazon natives would prefer ipe..I have some friends with some sweet ipe longbows, and Kowechobe's longbow graces the first page of my article on ipe in Aug. PA. Pyramid style works well since it give the back of the bow more area.

  We just don't have the lapacho tree( ipe) growing here so boards are the only option. It's not a bad one personally since I feel like a kid in the candy store when I go to the yard and see a mile of fresh wood to pick through..

So use bamboo or hickory on the ipe, but don't be afraid to try a selfbow since its only going to cost a few bucks for the wood..

Rich-
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: mullet on November 28, 2007, 11:39:01 pm
  Hey Rich,What do you think about backing Ipe with Hard Maple?Since I have some lam's for free and was told I have some Ipe arriving tommorrow thought I might give it a try. :D
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Rich Saffold on November 29, 2007, 01:24:31 am
Eddie, I would use it.  On a heavier bow I might use 1/4" or more backing.  I have had good results using nearly 50% bamboo thickness on a  r/d elb styles using very dense ipe. Really lowers the limb mass and does good things to the arrow speed so don't be afraid to venture in this direction.

Title: Re: Tension & Compression -Ipe vs. Osage
Post by: ShinneryOak on November 29, 2007, 05:19:09 pm
Thanks for the replies. Rich, I read your article, still have the issue with your first Ipe article. I've made a couple of attempts with Ipe since then but never had any luck. A few questions for you-first, how do you make a selfbow (unbacked) from Ipe boards? Just like a "decrowned" selfbow? Also, Ipe is rare as hen's teeth around here. I tried mail ordering some but got a piece with crooked grain which broke. Any reliable mail order source?   
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: mullet on November 29, 2007, 05:26:55 pm
 Just got the Ipe this morning,sure does look good.When it comes to bending this wood which is best,heat gun or steam?
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Pat B on November 30, 2007, 12:05:14 am
Eddie, Most of the tropicals are difficult to bend with heat. If you are gonna back it and want reflex, pre-tiller the belly wood first then add the backing with 3" to 4" of Perry Reflex. For a recurve you will probably have to cut the tips horizontally, add a spline and and clamp into a recurve form.    Pat
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Rich Saffold on November 30, 2007, 06:47:22 pm
Shinnery Oak, Selfbows take a board which can have a perfect back, or one where a good ring can be reached for the back..Also humidity plays into this a bit..Amazon natives don't have a problem, and some of their bows look similar to the same ones I have made.. Ipe is the name for the lapacho tree and there are a 100 sub species all dense, and fairly straight. There are boards which look almost like a dense black walnut board which I would make a selfbow out of. I don't always see a board like this at the yard, but I do find plenty which work great with a bamboo backing. 

I have found it much easier for most to tiller out a blank with bamboo on the back as opposed to a selfbow..Partially because ipe being so dense is much different than NA woods, and this causes folks to try and string these bows when they are too heavy for their design or have a small hinge somewhere which get exxagerated in the limbs since they are smaller relative to "normal" bows.. Getting a perfect curve floor tillering is what I do and I make sure it's not too hard to string..even on the heavier ones..When I string an ipe selfbow for the first time it looks like a finished bow, and then I finish tillering it with the string on.. Yes its more challenging, and a bit gut wrenching, but the results have been worth it..and if over time it lifts a splinter due to grain or dryness, then a backing will solve this..

The backed bows have proven themselves in the driest and wettest of conditions..Selfbows generally like a bit more humidity.  Just make it longer for drawlength, and if it holds up the shorten it if you want more poundage...
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Coo-wah-chobee on November 30, 2007, 06:52:04 pm
                      Like Rich said. Ipe calls hope the tropical jungles. It likes humidity like he said. Grease a selfbow good and keep it greased and if made properly should not lift a splinter. If it does like Rich said back it.........bob
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Pat B on November 30, 2007, 11:27:18 pm
This is a bit off the wall but does ipe handle sinew well. ??? As oily as it is I would kinda doubt it.  Being that it isn't effected much by humidity, it might be the perfect wood for sinew backed bows in the South and Eastern US.    Pat
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Coo-wah-chobee on November 30, 2007, 11:29:28 pm
...............Ipe LUVS sinew. Have made many of em'.Try it Pat ya will like it. Ya gave secret away hahaha ! ;D ;D....bob
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Pat B on November 30, 2007, 11:31:10 pm
What glue? What to degrease with? Any other secrets? If they are TOO secret, PM me. ;D    Pat
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Coo-wah-chobee on November 30, 2007, 11:37:52 pm
 Glue is hide glue of course, degrease with white wood ash and water (Paste )like but a little runny. Ha ! Remember most foks said "no-no ipe cant make a unbacked selfbow" Lots of secrets hahaha !. ;D.........bob
Title: Re: Tension & Compression -Ipe vs. Osage
Post by: Pat B on December 01, 2007, 01:33:30 am
 ;) Mums the word!!! 8)      Pat

ps. I'll give the ipe a try. I've wanted to try another sinew backed bow ... a shorty.