Primitive Archer

Main Discussion Area => Bows => Topic started by: DC on February 07, 2019, 11:40:52 am

Title: String lift off
Post by: DC on February 07, 2019, 11:40:52 am
This is a picture of my current favourite bow at 27" draw. My normal draw length is 26.5". To me it looks like the string is just lifting off. Is there any advantage/disadvantage to having it lift of a bit earlier if I pike it a bit? The reason I ask is that with the almost 90° hooks it's a real pain to brace and also it looks like the string is barely hanging on to the nock. It's never come off but it makes me think every time I brace it. I think if I take an inch off each end it would help both things. I could also glue the tips on at a better angle to help the string drop into the nock better.
Title: Re: String lift off
Post by: Pat B on February 07, 2019, 11:47:18 am
I'd leave it be. Are you using a stringer? That would make bracing it easier.
Title: Re: String lift off
Post by: bradsmith2010 on February 07, 2019, 11:53:03 am
when ever I did that,,,,it slowed the bow down,, (--) also,, dont mess with your favorite bow,,, :D
Title: Re: String lift off
Post by: sleek on February 07, 2019, 11:53:19 am
That looks ideal to me. Piking it will do 2 things. Increase overall draw weight, and increase the amount of weight gained per inch of draw in the last few inches of draw, or more simply put, increase stacking.

If you want to see what piking it will do without cutting the tips down, cut a small block of wood and glue it where you want your new tips. Shape it so the mating surfaces match the curve of the recurve. You can then carve a string groove in the block and make a new string to fit.

If you arent looking for a change in performance and are only concerned about the string coming off and want to redo your tips here is a good looking idea. Just like you did an over lay, gring flat the sides of the tip and do a side lay. Then do a new overlay on top of that. Ta Da! Brand new tips. I have done it and it looks beautiful. 
Title: Re: String lift off
Post by: DC on February 07, 2019, 11:53:49 am
No, I'm not using a stringer. Wouldn't I have to use a double groove nock for a stringer. Here's a picture of the other tip at brace. It doesn't look quite as iffy as it is in real life.
Title: Re: String lift off
Post by: bradsmith2010 on February 07, 2019, 11:56:41 am
DC,,,please start another bow,, ok,, (=)
Title: Re: String lift off
Post by: Pat B on February 07, 2019, 11:58:30 am
The stringer I use has a cup at each end for the tips.
Title: Re: String lift off
Post by: hoosierf on February 07, 2019, 12:10:02 pm
I think putting string grooves on the sides, smaller loops, and maybe fewer strands would make it secure and won’t change anything else and isn’t to much effort. Stuff like this is why I have about a dozen and half “spare” strings laying around.
Title: Re: String lift off
Post by: PatM on February 07, 2019, 12:27:18 pm
You can make your back groove a bit deeper.
Title: Re: String lift off
Post by: DC on February 07, 2019, 12:38:51 pm
DC,,,please start another bow,, ok,, (=)

I thought I would get a "before" speed. I've been shooting this bow steady so it has maybe 1000 shots. With my machine I got 194fps with a 400gr arrow, the same as it was new. Maybe I should leave it.
PS Turns out the bow is 45#@28". Speed at 10gpp is 184fps

PatB I'll do some searching for stringers. I can't see how I can make a cup small enough to be able to slip the string on.

PatM Do you mean add a deeper groove just past the existing one.

Any pictures of stringers would help. :)
Title: Re: String lift off
Post by: DC on February 07, 2019, 01:07:24 pm
OK I lied. I tested the draw weight and it is 45@28" so I found a 450 grain arrow. It shot 184fps. That sounds a little more realistic. Sorry about that.
Title: Re: String lift off
Post by: bradsmith2010 on February 07, 2019, 01:16:58 pm
Wow nice shooting,,,congrats on that
Title: Re: String lift off
Post by: sleek on February 07, 2019, 01:25:27 pm
OK I lied. I tested the draw weight and it is 45@28" so I found a 450 grain arrow. It shot 184fps. That sounds a little more realistic. Sorry about that.

I wouldnt mess with it. And if you are inclined to rework it, ill trade ya that bow for another set of staves :)

Lets get some full draw, braced and unbraced shots of it!
Title: Re: String lift off
Post by: PaSteve on February 07, 2019, 02:07:41 pm
DC you're a much more experienced and talented bowyer than myself...but I can say if I got that kind of performance I wouldn't mess with it. Here's another option for a stringer. It works good with recurves and should work with small tips.
Title: Re: String lift off
Post by: DC on February 07, 2019, 02:20:35 pm
That is one option but I thought I remember reading that that kind of stringer loaded the limbs unequally and wasn't good for the bow. I could be wrong, I'm green as grass when it comes to stringers.

I'm wondering if I can get away with cutting another notch like the wiggly white spot in this picture. If I make the loop small enough it looks like it would stay in. It's the only way I can think of that will allow me to slide the string up the recurve. I'll make the tips a little longer on the next bow.
Title: Re: String lift off
Post by: PatM on February 07, 2019, 02:23:40 pm
I meant just file the groove deeper into the horn part.
 I string these type of bows by just placing the tips between two chunks of wood on the ground and pressing down the handle and slipping the string into the groove.

 Like a stringer but nothing gets in the way.
Title: Re: String lift off
Post by: DC on February 07, 2019, 02:28:14 pm
Thanks Pat I'll think about that. Sounds like a good idea. Meanwhile this is what I was thinking in the last post. It would fit a bit better if there was a groove there.

PS I did file the grooves a little deeper so that part is better. The string seats decently now.
Title: Re: String lift off
Post by: DC on February 07, 2019, 02:37:02 pm

 I string these type of bows by just placing the tips between two chunks of wood on the ground and pressing down the handle and slipping the string into the groove.

 Like a stringer but nothing gets in the way.

I just tried that. It works pretty good. :D Have you ever had a tip pop off? They probably get a little scuffed but i can deal with that
Title: Re: String lift off
Post by: ohma2 on February 07, 2019, 02:39:47 pm
I think you are ok with that ,that loop isnt coming out of that.id leave it alone and trust it.
Title: Re: String lift off
Post by: PatM on February 07, 2019, 02:41:49 pm
  I make the tip shaped so that the pressure is distributed well so nothing pops off.  I'll also use pieces of wood that have a bit of a dent etc. to slightly cup the tips.  Soft chunks of wood will dent anyway.
Title: Re: String lift off
Post by: DC on February 07, 2019, 02:44:43 pm
There's a couple of picnic benches at the range. I could probably slide them around a bit.
Title: Re: String lift off
Post by: PatM on February 07, 2019, 03:36:07 pm
I use chunks of firewood, logs etc.  Anything stable that can be placed at the right spacing works great. You can find something pretty much anywhere.
Title: Re: String lift off
Post by: Danzn Bar on February 07, 2019, 04:01:20 pm
Please excuse me but PatM I'm have a problem visualizing the stringing with two chunks of wood.  would you please provide pics.?
Thanks
DBar
Title: Re: String lift off
Post by: PatM on February 07, 2019, 04:05:41 pm
Can't post pics.  Should be clear if you take a sharp recurve and try it.
Title: Re: String lift off
Post by: DC on February 07, 2019, 04:40:20 pm
There ya go! posts should be a little wider so they don't wobble as much :D
Title: Re: String lift off
Post by: PatM on February 07, 2019, 06:12:06 pm
Having them wide side down is much more stable.   You only need enough room  for the handle to be pushed down far enough.   

 That shows the method well though.
Title: Re: String lift off
Post by: Badger on February 07, 2019, 06:16:40 pm
  I think your curves are timed just about perfect. It starts lifting off pretty early and is just about finished when you hit full draw.
Title: Re: String lift off
Post by: Badger on February 07, 2019, 06:20:02 pm
  Is that bamboo backed osage??  very good looking bow.
Title: Re: String lift off
Post by: Scyth on February 07, 2019, 06:25:37 pm
. . . possible thought . . . a string bridge . . .

regards,

Scyth
Title: Re: String lift off
Post by: DC on February 07, 2019, 06:25:57 pm
It's bamboo Yew. I posted it here https://www.primitivearcher.com/smf/index.php/topic,64730.0.html

The bow shown in the bracing photo isn't the one in the other pictures. I just grabbed one that was leaning against the wall.
Title: Re: String lift off
Post by: Badger on February 08, 2019, 08:17:50 am
  That's my favorite profile, Mark St Louis influence. I don't do many like that but really like it.
Title: Re: String lift off
Post by: DC on February 08, 2019, 08:22:25 am
I can't seem to break away from it now. I start on what will be nice straight bow and the next thing I know I've cut it in half and I'm splicing in deflex. It's starting to worry me ;D ;D
Title: Re: String lift off
Post by: Hawkdancer on February 08, 2019, 09:31:45 am
Hide your saws! :BB >:D (lol). I live close enough to the range to string at home, or just put my stringing tree in the suv!.  I like the idea of the Blocks as well.  They are a few inches longer than brace height?
Hawkdancer
Title: Re: String lift off
Post by: DC on February 08, 2019, 09:56:11 am
I just grabbed those blocks for the picture. They are kinda unstable for stringing a bow. You can see the one on the left tipping over. Like Pat says wider than tall is better. A couple of tables would work better.
Title: Re: String lift off
Post by: Badger on February 08, 2019, 10:29:30 am
Adjustable
Title: Re: String lift off
Post by: sleek on February 08, 2019, 02:32:32 pm
Adjustable

Hard mount those on a board, maybe on sliding tracks, with a boat winch in the middle to crank down on the handle, and you can have a heck of a tool.
Title: Re: String lift off
Post by: Danzn Bar on February 08, 2019, 03:33:44 pm
Got it
Thanks
DBar