Bamboo backed Ipe

[Mesophilic]

A couple of months ago I started this thread about a bamboo backed Ipe fail.

http://www.primitivearcher.com/smf/index.php/topic,67596.msg949420.html#msg949420

Well, the guy gluing up the staves sent me a replacement and I got it finished up.  He's pretty active on YouTube so if anyone is thinking about ordering on, PM me and I'll confirm who he is.

My ultimate goal here is to see if a bamboo backing will hold up to my ultra dry high elevation conditions without tooling up to work with bamboo backings and the stave was pretty affordable to have someone else glue it up.

There were two major issues with the bow blank on this second go around. 

1) he again used Ipe with questionable grain runout on one of the limbs.   

2) near the fade area of the upper limb, the Ipe belly was much thinner than the lower limb and had an aweful hinge from the get go.

Between these two issues the tiller came out with alot on inner limb bend as I didnt want to thin the Ipe too much out to where that runout started.  It shoots with a little hand shock,  but not too noticeable.

I'll email him and let him know my thoughts.

Anyway, 66" NtN and 52# @ 28".  Shoots 550 gran arrow at 165fps average.  The handle is built up with oak and cherry, the nocks are scrap pieces of stabilized oak, and the strike plate is piano key ivory.

[Pat B]

Too much bend about 6" above and below the handle and none beyond that. Each limb and each section of each limb should do their share of the work.

[PatM]

You must be holding it upside down.

[HH~]

That glue up hadle is purty.
 
The upper limb looks a little flat but in the pic its kinda hazy.

HH~

[Mesophilic]

Too much bend about 6" above and below the handle and none beyond that. Each limb and each section of each limb should do their share of the work.

I agree, just wasnt sure what to do about that ipe grain runout.  Alot of lessons learned here.  If it can hold up as our weather dries out to single digit humidity levels, then I'm thinking a properly tillered bamboo backed bow might be the way to go and may look in to commissioning  one.

You must be holding it upside down.

Well, I shot it both ways for a few dozen arrows to see how it felt, and chose which limb felt better up.  Then inlaid the strike plate.

[PatM]

I meant that the worse hinge is in the top.

[Pat B]

Can we see an unbraced profile?
If you live in a dry climate you should try hickory, both selfbow and boo backed. Hickory shines at about 6% m/c.

[PatM]

If you want a bow to survive in a dry climate, make sure it's built in one.

[Mesophilic]

Can we see an unbraced profile?
If you live in a dry climate you should try hickory, both selfbow and boo backed. Hickory shines at about 6% m/c.

Pic below as requested.

I've played with hickory a bit, and haven't been able to get much performance out of it.  I haven't had hickory break on me yet so that's a good thing, but I can't seem to get a hickory selfbow abovr 10 gpp arrow faster than the high 150's fps.  I know that's fine for a deer sub 20 yards but I have my sights set on elk one day.  I think good chunk of that is I can't seem to master the art of heat bending recurves in to the tips. 

As much as I want to make it work, making bows may not be my thing.  Might have to consider procuring my dream bow another way.

[PatM]

There must be some other issue preventing better speed.  Are you sure your Hickory is getting as dry as you think it should.

[scp]

Anyway, 66" NtN and 52# @ 28".  Shoots 550 gran arrow at 165fps average.

It's almost incredible that the bow performs so well in spite of the hinge. It clearly has the tillering issue. The belly Ipe is way too thinner at the hinge. If anything, it has to be thicker where there is the grain runoff issue. The hinge will get worse over time. It has to be addressed.

[Mesophilic]

There must be some other issue preventing better speed.  Are you sure your Hickory is getting as dry as you think it should.

My last hickory stave.  My only testing option right now. 

[PatM]

What sort of design were you using and how was your tiller?

[Mesophilic]

What sort of design were you using and how was your tiller?

My best one is a 66" flat bow that BowEd helped me work out some specs.  It's 60# at 28", and has thin rigid tips.  Attempted to toast the belly but in hindsight I think I needed to keep the heat gun on it longer.  I can't remember the exact numbers but it shot a 550 grain arrow right around 160 fps.

I got to thinking, and I do need a lower poundage bow for working on thumb release.  How much more ipe could I safely tiller off of this bamboo backed ipe?  Or should I just ride it out and keep shooting it to see if it fails at that hinge? 

[HH~]

I would not be concerned what that chrono says. Get the bow tillered correctly and if it turns out 35-40lbs itll shoot fine and you can hunt with it. The boo you have used looks un-planed? Would be good to have planed it out and have it thin where limb works and tips and thick in handle and fades. This goes a long way to proper tiller on a Boo backed R&D bow. Your bows profile looks good. Get the outer third of bow limbs working or that ipe will give it up on inner third.
 
Think that shape bow would do great with a Planed bamboo backing, a thin tapered hickory lam core and a osage belly (solid with riser section). Then glue up tiller like any other bow. Can glue reflex in or R&D. Just think Osage is better on compression side for belly wood. They are super fast and with that hickory lam in there are very forgiving. You dont have to R & D for the speed your looking either just glue in 3-4" of reflex and have at it.

Again with a solid belly section you got to make sure there is no grain run out to edges on belly side.

HH~