Expert bowyer eyes needed

[TNFrog]

Hi All,
About 2 years ago, I ordered a custom bow. I finally had the opportunity to shoot it more than once here and there. During the past sessions, i have had the string come off the bow while the arrow was being released. This has happened 4 times now. At first I thought that I had somehow rigged it wrong. Since the string came back and cut my left wrist,(i'm right handed) and left a couple of welts, I made sure that the string was properly secured and centered in the notch as well as checking the brace height every single time. Still, this is the third time the string has come off, despite checking everything and even changing string. I know that there are expert bowyers on this site and want to get feedback on the notches specifically. Do you see anything wrong with one of them or both? This is getting to be frustating and its' starting to create bad shooting habits.

[Kelly]

Recurve or longbow?

[TNFrog]

reflex deflex longbow

[jrstegner]

I'm by no means an expert, but I have built a few. I'm guessing that is a recurve. The top picture looks like the nocks were not cut in evenly. That will eventually result in severe limb twist, which can cause the string to jump off. Also, from the picture it appears the nocks were filed at a 90°. That is why you have those cracks in the glass. I'd be surprised if your string loops aren't  badly frayed. Eventually you are going to get moisture in there and have a delamination at the tip. I'd get a new bow.

[Possum Head]

I'm by no means an expert, but I have built a few. I'm guessing that is a recurve. The top picture looks like the nocks were not cut in evenly. That will eventually result in severe limb twist, which can cause the string to jump off. Also, from the picture it appears the nocks were filed at a 90°. That is why you have those cracks in the glass. I'd be surprised if your string loops aren't  badly frayed. Eventually you are going to get moisture in there and have a delamination at the tip. I'd get a new bow.

Seems your advice is correct but couldn’t the angle of filing be feathered in at this point and the shoulders evened out? Also, Frog send this post to the Boyers Bench forum for more advice. Sure hope you hear what you want to!

[TNFrog]

thank you. Much appreciated.

[Pat B]

Is the limb twisting as the bow is drawn?

[TNFrog]

not as far as i can tell

[Kelly]

Besides what has already been said, you might be torqueing the bow handle causing the limbs to turn, hence unstringing itself.

[Kelly]

What does the other side of limb nocks look like?

Also do you have a picture looking down the string belly side from one end to the other when it is braced so we can see if the string runs down the center of bow?

[Roy from Pa]

What does the other side of limb nocks look like?

Also do you have a picture looking down the string belly side from one end to the other when it is braced so we can see if the string runs down the center of bow?

What Kelly said..

[TNFrog]

Here you go. Thanks again for the help.

[TNFrog]

other batch of pics

[Orion]

The nocks could be worked a bit on the belly side of the bow.  I don't think they need to be made deeper, but the sharp edge/angle should be reduced.  It looks like the glass is already beginning to splinter on one of them.  That's a precursor to delamination. Reduce that angle and put a little super glue in the cracks if they remain.

How long is the bow and how long is your draw length?  If it's a short bow and if you have a very long draw length, you could just be pulling the string right out of the nocks at full draw. Of course, a severe torquing of the bow or a severely twisted limb could also cause the string to come off.  However, I don't see anything in the way the nocks are cut that would cause it.  String wear and potential delamination, yes, but not throwing the string.

One other thing.  Smaller loops would help keep the string on the bow.  Strings can go through some very unusual ocilations at the loose.  If the loops are big enough, that flopping around of the string (even though you can't see it) could cause the string to come off the bow. 

[TNFrog]

last pic

[TNFrog]

How long is the bow and how long is your draw length?  If it's a short bow and if you have a very long draw length, you could just be pulling the string right out of the nocks at full draw. Of course, a severe torquing of the bow or a severely twisted limb could also cause the string to come off.  However, I don't see anything in the way the nocks are cut that would cause it.  String wear and potential delamination, yes, but not throwing the string.

One other thing.  Smaller loops would help keep the string on the bow.

Thanks for the tip, the bow is 56. #50 @ 28". I actually draw at 27-2.75

[Orion]

Pretty short, but I doubt your draw length is causing it. 

[TNFrog]

I don't think I torque it. I hold the bow with thumb and index and the 3 other fingers are seentially curved in, not grabing the bow.

[TNFrog]

One other thing.  Smaller loops would help keep the string on the bow.  Strings can go through some very unusual ocilations at the loose.  If the loops are big enough, that flopping around of the string (even though you can't see it) could cause the string to come off the bow.

Duly noted. Thanks again

[Overspined]

Loops are too Big on string. Try them where they’re just able to get over the nock.

When the string returns to brace its causing a forceful slack in the loops and then it will drop past brace before returning. So it’s causing the loops to slack and pop off. Simple fix