Sinew backing green staves

[JW_Halverson]

Mike Yancey at Pine Hollow longbows does it all the time. I have roughed out 2 green Osage staves and heat bend them on a R/D caul for a couple weeks and then applied sinew and let them cure together for 6 months and finished them off. No problems.

Correct me if I am wrong, but I do believe Mike does not use hide glue, but rather he uses TiteBond glues.

[loefflerchuck]

PatM- Is it lateral shrinking or moisture escaping too fast from the belly that cracks? I would not argue either way, but both a strip of tape or a coat of hide glue on the belly prevent this. I just finished a sinew osage bow. The sinew was curing 6 weeks before I tillered it removing the glue and it split from handle to tip. This is the first bow that split that long after sinewing. Like all the other bows that this happened to it shoots great but to others it looks broken.

[loefflerchuck]

I've made plenty of sinew backed bows from green wood. They turn out good but like has been said, waiting for the wood to season is best. I like to shape the wood green with steam, but then let the stave season before backing.

One thing to keep in mind is to use compression or tension staves. Side split staves may warp as they dry after sinew backing.

[High-Desert]

I always assumed it was the belly drying faster than the back because of the sinew layer. I tried the tape on the belly, which worked until I removed it and began tillering. Ever sinew moving to this desert environment, I've had every sinew bow crack on me, no failures, but it bothers me and I'm trying to find a method to avoid it.

[PatM]

Probably a bit of both but ultimately if it's cracking after then the sinew matrix  must still  be shrinking in width.

[PEARL DRUMS]

Mike Yancey at Pine Hollow longbows does it all the time. I have roughed out 2 green Osage staves and heat bend them on a R/D caul for a couple weeks and then applied sinew and let them cure together for 6 months and finished them off. No problems.

Correct me if I am wrong, but I do believe Mike does not use hide glue, but rather he uses TiteBond glues.

No. He rips the bark and sapwood off from green staves with zero regard to grain or violations. Then he slaps a crap load of sinew and TB3 on and leaves it for however long, then he makes bondo with TB3 and sawdust using it fill in the sinew job and sits it aside to dry. Then after its dried he rasps the bondo smooth and into a shape he wants. Then he adds rawhide over that and most often add skins on top if that.

[BowEd]

Mike Yancey at Pine Hollow longbows does it all the time. I have roughed out 2 green Osage staves and heat bend them on a R/D caul for a couple weeks and then applied sinew and let them cure together for 6 months and finished them off. No problems.

Correct me if I am wrong, but I do believe Mike does not use hide glue, but rather he uses TiteBond glues.

No. He rips the bark and sapwood off from green staves with zero regard to grain or violations. Then he slaps a crap load of sinew and TB3 on and leaves it for however long, then he makes bondo with TB3 and sawdust using it fill in the sinew job and sits it aside to dry. Then after its dried he rasps the bondo smooth and into a shape he wants. Then he adds rawhide over that and most often add skins on top if that.

Well...that oughta make em bomb proof!!!

[BowEd]

That belly cracking must be a pretty powerful force yet then especially in an arrid enviornment.Even enough to crack horn also on turkish bows I've read if below 30% humidity.I've been lucky I quess but will remember to use tape or something from now on especially if a lot of sinew over 3 ounces is used.Maybe putting on the sinew in stages will help with that too.A little at a time a week apart.
Personally I've sinewed quite a few bows with 3 ounces maybe the most overall.I usually do it in 3 sessions.4 to 7 days apart.Usually with dried wood too.I'm sure my area is more humid than yours but I've never experienced those cracks yet.Annoying I'm sure.I usually keep it in a cool place the first couple days is all for it to gel and set properly.Then out into a warmer area with a little air flow by it maybe.I keep humidity gauges around to monitor things myself.
Keeping it a cool enviornment at first a while to slow that drying down and even upside down[back to the floor] by the floor level in a more arrid enviornment like yours that is.Using a humidity gauge to keep it above 45% to 50% humidity at least in the beginning stages.Possibly in the bathroom??All things to slow that drying process down some so it does'nt dry or shrink so fast.
I'm wondering if you see cracks lengthwise on your sinew while drying also?Because it drys from both sides also.That can be a problem of too thin of hide glue used too.
It sounds like you know what your doing though.Good luck.
 

[PEARL DRUMS]

 

Mike Yancey at Pine Hollow longbows does it all the time. I have roughed out 2 green Osage staves and heat bend them on a R/D caul for a couple weeks and then applied sinew and let them cure together for 6 months and finished them off. No problems.

Correct me if I am wrong, but I do believe Mike does not use hide glue, but rather he uses TiteBond glues.

No. He rips the bark and sapwood off from green staves with zero regard to grain or violations. Then he slaps a crap load of sinew and TB3 on and leaves it for however long, then he makes bondo with TB3 and sawdust using it fill in the sinew job and sits it aside to dry. Then after its dried he rasps the bondo smooth and into a shape he wants. Then he adds rawhide over that and most often add skins on top if that.

Well...that oughta make em bomb proof!!!

Something like that

[bubby]

Mike Yancey at Pine Hollow longbows does it all the time. I have roughed out 2 green Osage staves and heat bend them on a R/D caul for a couple weeks and then applied sinew and let them cure together for 6 months and finished them off. No problems.

Correct me if I am wrong, but I do believe Mike does not use hide glue, but rather he uses TiteBond glues.

No. He rips the bark and sapwood off from green staves with zero regard to grain or violations. Then he slaps a crap load of sinew and TB3 on and leaves it for however long, then he makes bondo with TB3 and sawdust using it fill in the sinew job and sits it aside to dry. Then after its dried he rasps the bondo smooth and into a shape he wants. Then he adds rawhide over that and most often add skins on top if that.

Well...that oughta make em bomb proof!!!

Something like that

Talk about adding excessive weight😐

[Bob W.]

J.W. Pearl answered your Titebond queastion.

[hoosierf]

I think TBBI talks about belly splits after sinewing and the authors concluded it is almost never fatal as long as there is no grain runoff and that lateral shrinkage of the sinew causes it. If that’s the case I’m shocked a piece of tape helps...most interesting.