Why do my arrows fly better with the bow upside down!

[Tommy D]

I have a sinew backed osage bow that I am very fond of - a while back I heated in some reflex-deflex and backed it with sinew as it was taking some set (it used to be a self bow). It is also a takedown. The bow is a little snakey and twisted, and of course with the sinew I cannot now heat treat it to straighten/ adjust it at all.

I feel that it is tillered ok and since the string sits to one side, I made this the side for the arrow shelf and rest. I am shooting arrow dynamics trad lite arrows which are normally very forgiving to shoot, yet I can't get them to fly straight or consistently.

I have tried the following:

1) really heavy/ light points
2) longer/ shorter shafts
3) building up the arrow shelf (to ridiculous amounts)
4) changing string height and nock point

And none of these things seem to make much difference.... yet ....

5) if I turn the bow upside down (see picture) (so it looks way off center shot), the arrows fly great.

Is this purely an arrow spine problem, or could it be that the bow prefers to be shot this way? It is a little uncomfortable, but the arrows do seem to zing out of it.

Am I going to mess up the tiller like this?

Do I just accept that this is how it turned out or are there any other solutions I am missing? Perhaps shortening a limb slightly...

Here are some pics...



Bow Right way round, with arrow on shelf



Bow turned upside down, with arrow shot off takedown handle/bow wood joint. Note it sticks out left and looks awkward.



Bow strung - right way round - note string is close to center shot of arrow rest.

[George Tsoukalas]

I've had that happen too. I think it is because the arrow slap throws off the arrow.

I am a righty. If the string is off center to the left I usually flip  the bow around. It ends up being quieter on release and I get better arrow flight.

Jawge

[Buckeye Guy]

It's  probably  just what Jawge said but for future trys be careful  to notice as veiwed from the back not belly the overall lay of the twists and turns of your bow to see better where the more true lay of the string .
 The greater percentage of the bow may be twisted to a much differant location  then you are seeing at the handle
That gives you a much better pic of what can be going on and one more reason to not shape the handle till the bow is tillered out and shooting
I would just redo the grip and enjoy this one as is
Have fun
Guy

[sleek]

Try shotting a stiffer spined arrow if you prefer shooting your bow as built. Or just turn it upside down and reshape your handle, if you can.

[George Tsoukalas]

Yes, I see that the handle has a rest cut in. Is that correct Tommy?

As Sleek mentioned, in the future, leave the handle full width until at least first stringing and shape it track the string better.  Also, leave the nocks full width and cut one end further on both top and bottom nocks. So, in your example you would cut the nocks on the left side further in bringing the string towards the center.

As is can you ove it with a heat gun after coating  with some grease?

Jawge

[sleek]

Jawge does greawe protect sinew when using heat?

[Tommy D]

Thanks for the responses guys... as I mentioned the bow is a takedown, so that side was naturally geared towards being the side for the rest/shelf. In addition it was an unbacked bow that I liked, but that had taken set, so I heat treated it into a sort of reflex-reflex shape and added sinew.

Now of course (unless I am mistaken) I can't really heat treat it again with the sinew backing, or unglue the takedown sleeves and line them up again.

One option is that I could probably move the string back towards the center by adjusting the nocks as mentioned by George.

Like I said, arrow flys better upside down, but bow feels uncomfortable/out of balance to hold.

Do you think any of this could be a tiller problem - like the timing of the limbs coming fwds makes it more conducive to being shot upside down?

[Tommy D]

Not the best photos but they might help...

Back of Bow

Belly of bow unstrung



Bow strung

Full draw - 28 inches. Bow is 66 nth

Unstrung side profile

[Del the cat]

Note it sticks out left and looks awkward.
I'd say that looks correct.
Maybe you have it too close to centre shot when the bow is the "right" way up...
The sticking out left is what the archer's paradox is all about.
Even modern Olympic target recurves (spits on floor) have a little offset from true centre shot.
Out of interest try padding out the arrow pass by 1/4" and see if that improves it. (Unless that's what you meant when you said you tried building up the shelf?)
Del

[George Tsoukalas]

Thanks, Sleek. I missed that too. I'd say no on heating  a sinew backed bow. Sorry. Jawge

[George Tsoukalas]

Tommy,

One more thing...particularly if you cannot turn the stave around.

I once made a yew bow that came from a nearly perfect stave. It was really straight.

The stave was a gift so I want to do the bow justice. I even used calipers to make sure I was removing wood evenly from both sides of each limb.

However, when I strung it the string still leaned to one side. It was leaning to the left. Go figure.

I brought the string to the center by removing wood from the right side of both limbs slowly and with a scraper checking tiller frequently.

The upper limb is stiff mid limb on. Perhaps a little scraping on the right side of upper limb will bring the string to the right; bottom limb looks good. Up to you.

You may not have to touch the lower limb at all to even off the tiller.

Jawge

[Buckeye Guy]

Tommy,

One more thing...particularly if you cannot turn the stave around.

I once made a yew bow that came from a nearly perfect stave. It was really straight.

The stave was a gift so I want to do the bow justice. I even used calipers to make sure I was removing wood evenly from both sides of each limb.

However, when I strung it the string still leaned to one side. It was leaning to the left. Go figure.

I brought the string to the center by removing wood from the right side of both limbs slowly and with a scraper checking tiller frequently.

The upper limb is stiff mid limb on. Perhaps a little scraping on the right side of upper limb will bring the string to the right; bottom limb looks good. Up to you.

You may not have to touch the lower limb at all to even off the tiller.

Jawge

I was just thinking about it also and wondered if you could get it to twist a bit by that method
but I actully think there is a good bit that is stiff on both limbs that could be worked on to help bring it around
a little here , a little there and you may get what you need with out much if any reduced draw weight and may even shoot faster
listen to Jawge on this one and see where it goes

[sleek]

Or just shoot a much stiffer spined arrow. My guess is they go too far right when you shoot?

[bradsmith2010]

the string is not actually lining up like you have it positioned,, yes in the photo it seems to have the string across the handle in a certain way,, but when you actually draw the bow it has a different orientation,,than what it looks like at brace,,, so it shoots better off the other side,, or upside down,,this is quite common for a twisty self bow,, make the handle so you can shoot it the way it likes,, or adjust the tips and take more wood from the arrow side if the bow design will permit,,

[Tommy D]

Bradsmith - are you saying that you think that it is sort of an illusion that the string lies to one side and actually the bow is more center shot the other way  round if you count from the release point. In other words the braced picture is confusing things.

So you think I should make my cut out bigger?

I have my suspicions that the arrows might be too stiff - I shoot them from a much heavier center shot fiberglass bow of 78lbs and they fly dead straight. This bow is about 63lb.

I will try adding really heavy tips to the arrows and seeing if they fly better.