Strongly reflexed bow turning inside out!

[WhistlingBadger]

Well, dang it!  I've got a juniper/elk sinew bow on the tree.  The sinew put about 6" or reflex into it, which is great and should make a hard-hitting bow.  The limbs are a little snakey, but I got them unkinked enough that the string crosses the center of the handle.  But today I got it bending to about 8", put a string on it, and the thing turned itself inside out!  Is there any way to make it not do that, short of peeling off the sinew and starting over? 

[Hamish]

What brace height did you string it at?

You need to get it to the point where it can be strung at a decent brace height, at least 4". If you try and use a loose string or a low brace height even a moderately reflexed bow will want to "flip".

[Mo_coon-catcher]

I was just about to say what Hamish did. Highly reflexes bows pretty well need to be taken to full brace skipping the low brace stage.

Kyle

[Pappy]

What they said 😉😊😊 Pappy

[pierce_schmeichel]

Definitely do not take sinew off. If you need to make it bend more just take more wood off the belly very slowly. It is very very easy to remove too much wood when tillering a high reflex juniper bow. Once you get past that snap back point the bow doesnt have as much draw weight as you think. Thats actually one of the things that makes sinew backed juniper bows so darn powerful haha. Kinda straightens the draw weight curve out a bit.

[WhistlingBadger]

Interesting.  So the solution is to brace it higher.  That's counter-intuitive!  I'll give it a shot.  Thanks, guys.

[WhistlingBadger]

And tiller slowly, Pierce.     No problem there--this thing is so snaky I think I'm going to do most of the tillering with a cabinet scraper.

[Badger]

   Wood is not really suitable for highly reflexed bows. The reason is because a highly reflexed bow has to have very short working areas to maintain any kind of stability and wood will either break or take too much set if it doesn't have enough working limb. Look at the modern Asiatic bows, they have very short working areas. Your desing has to be able to tolerate the materials you are using.

[willie]

how much wood to sinew proportions? where is it designed to bend? a pic or two would be nice.

[WhistlingBadger]

I'll try to get some pics once I get it strung.  I'm a little nervous about trying it again, since juniper is so weak in flexion.  If it pops over backwards with a shorter string, I'm afraid the belly will break.  But nothing for it but to try, I guess.

[Bob Barnes]

I always clamp the grip to the tree when using the long string, but most of my bows have heat induced reflex.  Once I get it to brace height, and get a string on it, it's not a problem.

[Badger]

Bob, about how much reflex are you talking about? I find that the more reflex I have the stiffer my outer limb needs to be. About 4" is where it seems to really become an issue, unless the bow has already taken massive set, which is usssualy the case with highly reflexed bows.

[Bob Barnes]

Bob, about how much reflex are you talking about? I find that the more reflex I have the stiffer my outer limb needs to be. About 4" is where it seems to really become an issue, unless the bow has already taken massive set, which is usssualy the case with highly reflexed bows.

Steve my reflex caul only adds 2-3" of reflex, depending on the length.  Even 2" of reflex will cause one to flip on a long string sometimes, so I just clamp the grip to the tree.  I don't use more reflex than that because I don't enjoy hunting bows that are hard to string easily.  It sounds like WhistlingBadger got more than he wanted once the sinew induced more reflex.  An ERC belly won't like it I suspect.