Primitive Archer

Main Discussion Area => Bows => Topic started by: JNystrom on December 06, 2017, 01:30:16 am

Title: Sinew backing a twisted/missaligned stave
Post by: JNystrom on December 06, 2017, 01:30:16 am
Hello everyone!

This has bothered me for a while: will you have problems if you sinew back a stave that you heat corrected earlier? Will the moisture from sinew backing and sinew pulling to reflex missalign or twist the stave to its original form? I have some good osage staves for example that i would like to make short sinew backed bows, but they would need straightening before. I have done quite some heat corrections before, but what i don't have is experience with corrections and sinew back!
Any ideas?

Thanks in advance!
Title: Re: Sinew backing a twisted/missaligned stave
Post by: Pat B on December 06, 2017, 04:05:50 am
As long as the bow is tillered evenly and the sinew is applied evenly you shouldn't have a problem. I've heat treated just about every bow I've sinewed.
Title: Re: Sinew backing a twisted/missaligned stave
Post by: Stick Bender on December 06, 2017, 07:38:22 am
The last osage/sinew I did I heat corected reflex in and shellac the belly prior to sinew to minimise any cracks never got any cracks or deviations but the bow never made it to being a bow do to a weak spot on the mid/outers !
Title: Re: Sinew backing a twisted/missaligned stave
Post by: DesertDisciple on December 06, 2017, 07:40:10 am
I corrected and heat treated my sinew backed hickory and it held. Allow more time to cool and dry than you have patience for and you should be okay.
Title: Re: Sinew backing a twisted/missaligned stave
Post by: wizardgoat on December 06, 2017, 08:34:10 am
After making a bunch of sinew backed bows, I now only opt to use near flawless staves for then.
The process is so time consuming I just want the best chances of it surviving.
I've made small heat corrections with a fully cured sinew backing, on wood and horn bows.
I will add though, I've never made a sinew backed Osage bow.
Title: Re: Sinew backing a twisted/missaligned stave
Post by: JNystrom on December 06, 2017, 08:47:13 am
Good, I think this just gave me the courage i needed. It is true that you don't want to waste time on bad staves, so you have to keep that in mind also. Thanks again.
Title: Re: Sinew backing a twisted/missaligned stave
Post by: Stick Bender on December 06, 2017, 09:02:43 am
I agree with goat I had a lot of time processing 1100 grains of sinew and 16 weeks of cure time & the build on that bow before I had the issue I wont do it again on questionable stave sinew bows are forgiving but they dont mask bad wood !
Title: Re: Sinew backing a twisted/missaligned stave
Post by: JW_Halverson on December 07, 2017, 12:10:36 pm
I agree with goat I had a lot of time processing 1100 grains of sinew and 16 weeks of cure time & the build on that bow before I had the issue I wont do it again on questionable stave sinew bows are forgiving but they dont mask bad wood !

And even if you succeed in polishing a turd, take a good hard look at what have you got in your hand?
Title: Re: Sinew backing a twisted/missaligned stave
Post by: Limbit on December 07, 2017, 07:26:40 pm
I had that happen to a short sinew-backed mulberry bow I made once. While the sinew was drying on it, it twisted the tip on one side off alignment. Funny thing is that I had already left the tip quite thick just in case something like this happened. I think two things could have solved the problem now. 1: lay the sinew more carefully insuring that all the threads are totally straight. 2: keep the bow a bit longer or wider than you want so that you can shorten it or thin it if it decides to twist. Of course if it does a propeller twist, you are just screwed unless you leave the bow significantly thicker...which would eliminate the treated belly. In the future, I will be more careful when I select wood for a bow like this! My advice, just play it safe and use the best piece of wood you've got. Sinewing is a real time investment.