Author Topic: Update on 120# yew warbow - I don't like to complain, but...  (Read 49434 times)

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Offline WillS

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Re: Update on 120# yew warbow
« Reply #15 on: December 14, 2013, 06:36:57 pm »
Thanks for the replies guys! All very interesting.

So far, I've tried only Flemish twist, with very few twists.  In fact my last attempt had no twists at all.

I tiller with a pulley system, and I draw the bow on the tiller to around 6-8" then string it with the short string, and when I release the tension the short string just stretches out until the bow is flat again.   I've even tried taking the bow up to around 12" on the long string and doing the same, and always the string (16 strand FastFlight Plus) stretches out.  The string is well stretched before I use it (I always use my strings as tillering long strings before shortening and using as short strings)

I'm convinced I'm either doing something fundamentally wrong either with the string making (never had an issue before though) or the particular batch of FF is crap.  Doesn't sound likely though!

As for the sidenocks, Simon Stanley is a big fan of double bowyers knots on super heavy bows with side nocks, so perhaps that's the way to go.  Not sure.  Steve Stratton has been experimenting with the theory that the sidenocks were removable, and were always kept tied to the string, and the bow would be strung by slipping the nocks onto the bow each time.  I know Dave Pim made a stunningly gorgeous Italian yew warbow with removable side nocks.  I'll have to play around with them I guess. 
« Last Edit: December 14, 2013, 07:06:11 pm by WillS »

Offline Marc St Louis

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Re: Update on 120# yew warbow
« Reply #16 on: December 15, 2013, 09:07:48 am »
I only use endless loop with heavy bows and FF as I found that the material is too slippery for a timber hitch
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Offline WillS

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Re: Update on 120# yew warbow
« Reply #17 on: December 15, 2013, 09:12:01 am »
That's interesting, thanks.  I've yet to try an endless loop as it requires a long jig (I think?) and I always make up my strings in the hand, as it's dead simple to do a Flemish that way.  I've got enough of the FF+ left to try though, so perhaps that's the best way forward before buying more material. 

Del has been incredibly generous and offered to send me a string, which is most appreciated but my autodidactic nature needs to at least attempt a few!

Offline toomanyknots

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Re: Update on 120# yew warbow
« Reply #18 on: December 15, 2013, 10:23:13 am »
That's interesting, thanks.  I've yet to try an endless loop as it requires a long jig (I think?) and I always make up my strings in the hand, as it's dead simple to do a Flemish that way.  I've got enough of the FF+ left to try though, so perhaps that's the best way forward before buying more material. 

Del has been incredibly generous and offered to send me a string, which is most appreciated but my autodidactic nature needs to at least attempt a few!

There is an awesome guy on youtube called the backyard bowyer, he makes pvc bows, but he has a lot of tutorial videos on there. One of them is a tutorial for an endless loop string jig, I made one and it cost me like 20 dollars, and was real easy to make. I also made a serving jig from a video he has, and it works better than my 20 dollar one, and cost like a dollar to make. He's like an archery macgyver.
"The way of heaven is like the bending of a bow-
 the upper part is pressed down,
 the lower part is raised up,
 the part that has too much is reduced,
 the part that has too little is increased."

- Tao Te Ching, 77, A new translation by Victor H. Mair

Offline WillS

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Re: Update on 120# yew warbow
« Reply #19 on: December 15, 2013, 10:46:26 am »
I actually watched that earlier, it was pretty well explained and laid out.  Looks like a whoooooole lot of faffing about though, when compared to a double laid-in Flemish.  Don't need any sort of jigs for Flemish...

I dunno, this is pretty odd.  Plenty of bowyers and archers I know and shoot with use double loop Flemish for warbows, so I can't see why that's the issue here. 

Bear in mind that the bow isn't finished being tillered.  I can't finish it, because I can't brace it!  So I have no idea how heavy the bow REALLY is.  All I know is that it's about 115# when it's drawn to 8" or so on the long string.  It's highly unlikely, and conversations with Del have made it pretty clear, but I guess there might be a chance the bow is way too heavy yet.  I just can't tell because I've never taken the bow off the short string. 

One thing that's really weird is that whatever string material you use must eventually stop stretching?  But I'm using a really, really old and well stretched string and I keep shortening it to get the bow to brace, and of course it stretches.  When I take the bow off the tiller, the string is in both loops, but hanging slack.  So I shorten it again, and the same thing happens.  This has been going on for months now, as I can only really do any tillering at weekends.  I just thought that eventually the string would stop stretching, but it seems to have infinite stretch!

Offline Marc St Louis

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Re: Update on 120# yew warbow
« Reply #20 on: December 15, 2013, 01:25:41 pm »
It's obviously not stretching but slipping someplace, if you have loops then your loops are slipping
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Offline WillS

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Re: Update on 120# yew warbow
« Reply #21 on: December 15, 2013, 05:25:13 pm »
Yep you must be right!

Well I've made one more double loop Flemish, keeping everything as tight as possible,  so I'll see how that goes and if there's no improvement I'll move onto endless loop. 

Offline sleek

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Re: Update on 120# yew warbow
« Reply #22 on: December 15, 2013, 05:46:26 pm »
They say a proper glue joint is stronger than the original wood. Si I wouldnt sweat the split. I would wear a helmet though...
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Offline meanewood

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Re: Update on 120# yew warbow
« Reply #23 on: December 15, 2013, 07:12:37 pm »
What I have found with the bowyers knots on both ends, is the lower limb one does not slip because it is pushed tight against the nock and is then left alone but the upper limb knot tends to slip and needs regular adjustment. This is because it is constantly tightened and loosened when stringing the bow. I have found that you can lessen this effect by keeping the wrap loops of the knot close together and use five of them, they end up looking like a hangmans noose. This makes the knot easier to loosen when de-stringing because by twisting the knot, this bulky part lifts out of the side nock slot and you can then pull the loop down the limb, opening it up!

I have a theory that perhaps a bowyers knot may not have been used on the upper limb, even though they had side nocks.
Perhaps they used a system that is a self tightening loop instead of self tightening knot (bowyers knot) or a fixed loop.
In one of the Bowyers Bibles it shows a string with a very small loop ( probably formed as you would with an endless string) and then the string is passed through it. I think native Americans may have used it!
This in effect is a self tightening loop and gives the advantages of both loops and bowyers knots!
The small loop which is bulkier sits on the outside of the side nock the same as with bowyers knots. The advantage of this type of loop is it is easier to get on and off (like a fixed loop), it wont slip ( like a bowers knot) and it is self tightening (which is needed to spread the strain of a heavy bow string all around the horn nock)

I shall make one and try it out soon and pass on the results

Offline WillS

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Re: Update on 120# yew warbow
« Reply #24 on: December 15, 2013, 07:29:53 pm »
That would be good, always worth trying stuff out I guess.

I just asked Michael Heinz what he uses as he's made plenty of heavy warbows, and he says he uses FF+ 16 strands for bows up to 120# with two Flemish laid in loops, so there shouldn't be any problem with that.  I must be making the strings wrong for them to slip constantly the way they seem to be doing. 

It probably needs somebody used to using Flemish loops on warbows to see what I'm doing and tell me what's going wrong, but until I can find somebody I'll have to try endless loops I suppose.

Offline PatM

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Re: Update on 120# yew warbow
« Reply #25 on: December 15, 2013, 09:31:19 pm »
Sounds like you're twisting something the wrong way. Can you post a pic?

Offline WillS

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Re: Update on 120# yew warbow
« Reply #26 on: December 16, 2013, 03:29:38 am »
Yep, here ya go!

As far as I'm aware, nothing's twisting itself undone.  I've made Flemish strings the same way for years, and never had a problem before.  It's something to do with the weight I guess.  Something I'm doing is fine for low poundage bows, but can't hold up to the heavier stuff?!  No idea! 


Offline Del the cat

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Re: Update on 120# yew warbow
« Reply #27 on: December 16, 2013, 04:57:24 am »
You really need one good long non stretch string and one of these.
It will save you sooooo much grief.
It's the Del the Cat Adjust-a-string available at a workshop near you.
Del
Health warning, these posts may contain traces of nut.

Offline WillS

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Re: Update on 120# yew warbow
« Reply #28 on: December 16, 2013, 05:19:41 am »
If you box it up, and draw a bow on the front I'll give you fifty quid for it!

Offline WillS

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Re: Update on 120# yew warbow
« Reply #29 on: December 16, 2013, 05:41:05 am »
As a follow-on, how do you guys work out the correct length for an endless loop string?  Is it the exact distance of the bow nock-to-nock, then you twist to accommodate for the initial stretch, or do you make it shorter than the n-t-n length?