Questions about strings

[ssrhythm]

Not wanting to start a “what’s the best string and why” thread; I’m in the process of experimenting with B55 and D97 and will figure out which one will be best for my bow, but so don’t want to screw anything up experimenting.

1.  Does strand count affect the amount of shock imparted to the limb tips?  Specifically, would a 12 strand d97 be more harsh on the bow than a 16 string or vice versa?  Or is the strand count you choose simply based on the strength needed to ensure the string won’t break?

2.  Why exactly would you add padding strands at the loops?  To absorb more shock and transmit less shock to the limb tips?  Or is this to protect against wear there, or both.

Comparing my Jeffery Classic Hunter recurve to my new bow via chrono speeds, I shot a 10gpp arrow from each.  The glass bow shot 177; 179.  My new bow shot 164, 167.  I realized I was using a 14 strand d97 on the Jeffery and built a 16 strand b55 for it so it would be a more apples to apples comparison.  With the b55 string, the Jeffery bow lost ~10-12 FPS.  So…I figured I might gain similar speed by twisting up a 14 strand D97 for my new bow.  I padded 14 strand D97  loops with 6 strands of B55, but I made it a bit too long, had to twist it a lot, and I only picked up ~2 fps…if that.

So, my takeaway so far is that if you have to twist a string to shorten it…make a new string, because it seems that the twist rate is a much more significant  performance factor than type or strand count of the string itself.

[bownarra]

Yes you see some strings that are so twisted they are like coiled springs!
You pad loops on dyneema strings so they aren't like cheesewires inb your nocks.
Shock has nothing to do with it. Essentially a good bowstring is the 'shockiest' string.
Dacron strands tend to break around 35#. Dyneema around 70 - 80# per strand.
String strength should be around 4 x bow draw weight.
So you can see most bows could be shot wit ha 4 strand dyneema string....strengthwise....but not comfortable to draw.

[bassman211]

A 16 strand B55 string is like tying a small rope on your bow. Up to 55lbs any thing more than 10 strands of B55 is a waste of material. I tested a 40lb.  recurve  bow years ago with a stock 16 strand B50 string, a 10 strand B55 string, and a 10 strand D97 string. Through a chrony the stock string shot 148 fps. The 10 strand B55 shot 156 fps ,and the 10 strand D97 shot 162.fps. I now tie 8 strands of B55, or 8 strands of D 97 on my self made bows up to 45 lbs., and 8 strands of D97 on most of my gl--- bows. Besides that what bownarra said above. Not telling you to do any thing that I do . Just my personal experience. May help , or not.

[Hawkdancer]

I am wondering about the effectiveness of mixing strand types, specifically D97 and Fast Flight, for both Flemish twist and continuous loop.  Surely someone has tried that.  My understanding is that they are very similar.
Hawkdancer

[bassman211]

D97 is called FF. It is 100 percent dyneema.  BCYX, Mercury,  8125, 652, and others are all low stretch strings. The difference is others are made with a blend of  dyneema, and vectran. Thinner diameter,and more string count. No real advantage to mix them.

[Morgan]

When making both Flemish and continuous loop strings do you use the same strand count for both? Or does one get more than the other?

[bassman211]

Same, but it is good to pad the loops to ensure proper nock fit, and if you are not going to put hard tip over lays on the bow keep the wood tips thick.

[ssrhythm]

Thanks for the info.  I never knew the “why” behind “don’t use FF on Jon reinforced tips.  I haven’t done overlays yet, as I want to come up with a method to reduce shear forces from popping one off when on a hunting trip before I try them.  It seems like I would be good to go with a 14 strand D97 and padded loops.  My bow is 62.5 at 28” so Id be good to go with 12 strands, but I’d need to get some thicker serving material or double serve with what I’ve got.  Regardless, I’m going to make a 14 strand D97 and make it where I won’t have to add many twists…I like the 1 twist per 3-4” b55 performance, so it should be smoking with D97.

Thanks again.

[bassman211]

For serving I use a layer of B55, a layer of dental floss, and one more layer of B55, and bond with super glue. I add a little more thickness to the dental floss if the string is thinner, adjust to  the nock you are going to shoot from the bow. Many ways to work around proper serving. That is just my way.

[Yooper Bowyer]

I've always thought that superglue would do something nasty to a string, either chemically damage it or make it to brittle.  I think that mixing B55 with D97 wouldn't make much sense because the B55 stretches so much more; it wouldn't do any work and is rather heavy.

[bassman211]

My strings are 95 grains when finished. I use B55 only as serving material. Crazy glue has never had any negative effect on the serving portion of the string. I have built  in the hundreds of strings over the years ,and to date none have broken.

[mmattockx]

I haven’t done overlays yet, as I want to come up with a method to reduce shear forces from popping one off when on a hunting trip before I try them. 

This is one way to achieve that:



Cutting the limb tip at an angle adds surface area to the joint and orients the glue line more perpendicular to the string forces.


Mark

[Don W]

I've never had an overlay pop off. I've tried to remove some to shorten a bow and unless I cut them, they typically end up coming off in pieces.

How often do they come off? I've never heard or read that concern before.

[ssrhythm]

I've read on here (I think) of at least a couple of instances where a tip overlay popped off.  I know there is a hog hunting video that Clay Hayes posted where he popped a tip overlay off getting out of his vehicle before daybreak.  I can't remember what caused it, but I'm thinking he dinged it on something. Regardless, he actually was able to find the overlay on the ground outside his truck once he realized it was gone, and he was able to reapair it and continue on with his hunt.  Fortunate.

I'm hard on my equipment whether I'm trying to be or not, and I can absolutely see getting my bow tip slammed in a door or stuck in the crook of a tree on the walk in or having it not clear my stand during a shot etc...any number of things that could cause it to pop off.  If it can happen to anyone, I can assure you it will happen to me.

I'm wanting to experiment on some scrap limb tips and try to come up with some type of hidden pin system or maybe just actually drill a couple of very small diameter holes completely through the overlay and the bow tip and pin them with  matching diameter contrasting wood pins...or even aluminum or brass or copper pins...something soft that can be filed and sanded smooth and would actually look like an asthetic addition or compliment to the bow.

I'm pretty sure that all the failures I've read about were due to a shearing type of force.
I'm certain that something was not done exactly right with the glue line and/or glue-up on these failures, but I'm equally certain that none of the boyers that experienced the failures thought that they were doing or realized that they did anything wrong. 

I figure that the additional stability and structural resistance to shearing forces that might occur in the plane parallel to the glue line and the additional and directionally-different surface area of the pins for glue adhesion would make any well mated and properly glued overlay/bow interface absolutely bombproof...and for novice wood workers like me, it would add a little insurance to a job where an unknown mistake was made during the glue up.

I'm definitely going to try it on the next bow I've got roughed out and will start working on when I get beyond my upcoming Elk hunt.  If anyone wants to play with this idea and put it into action prior to that, I won't be jealous that you beat me to it.
 

I'm difinitely going to try it though, as I would absolutely come unglued (pun intended) if I got to my hunting destination only to figure out that my bow was useless because of a tip overlay malfunction.

[Gimlis Ghost]

I ordered a 12 strand B55 string for my Bearcat 35# 60" bow last week, it should be here tomorrow.

I chose the lowest strand count they had because of comments on this thread.

The Bearcat, at least this model year, has a very simple nock. I'm considering adding a tip overlay but wonder if it will stay in place on the glass backed limb.
If it isn't likely to make a noticeable improvement I guess I'll just leave well enough alone.