Author Topic: ELB Musings  (Read 16644 times)

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Offline Del the cat

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ELB Musings
« on: April 29, 2019, 05:11:11 am »
I'm building a 50# ELB flight bow (well on on the mk5 at the mo'  ::) )
There are so many contradictory factors and questions.
I realise there are no magic answers, but I'm wondering about 2 things...
1. How narrow can you go whist retaining stability? Brace height will be a factor in stability too... which brings me to question 2.
2. One could have a fairly high brace and also a short arrow if the grip is padded out on the belly side by say and extra inch, the down side would be the string could whack your wrist (mind this could help damp out limb vibration/shock  >:D ::) )
Effectively an extra inch on the belly at the grip would allow a 1" shorter arrow.
Any thoughts, comments? (Derision and laughter also accepted  ;D )
Del
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Offline JNystrom

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Re: ELB Musings
« Reply #1 on: April 30, 2019, 03:27:38 am »
1:1 (width to thickness) ratio bows are quite doable as long as string tracks completely in the middle and the bow doesn't have more than a inch of reflex.
I don't know about that grip padding though, doesn't make any sense. :D In contrast im quite used to low brace heights and i like the efficiency that it comes with.
Actually i haven't noticed really a big difference with low or "normal" brace height in stability. With hornbows they tend to wobble back and forth, but i guess not with wood bows. Not totally sure...

With my bows, the best i've managed after numerous heat manipulation to get them stay straight was 1" x 1" osage 140# @31" with 1" reflex in the beginning. 71" long.
Then some tonkin-ipe longbows, a bit lighter at 80-100 pounds or so,
Nr.1 a bit less than 1" wide x 3/4" thick with 1 1/2" reflex (100# @28"), 72" long
Nr.2 1 1/6" wide x 3/5" thick with 3" reflex (82# @26") 67" long
Those laminates were glued with snaky tonkin and hide glue was used. Hide glue was pretty great, since i had to heat them a lot to straighten the alignment of string. I don't know if this would have been possible with synthetic glues.

Offline Del the cat

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Re: ELB Musings
« Reply #2 on: April 30, 2019, 03:57:09 am »
Cheers, thanks for the response ... the tumbleweed was beginning to roll across the screen  ;D
Sounds like I'm in the right ball park as I'm down to 0.875" width, and the thickness is much less as it's only a 50#. :)
I wonder if a high or low BH is better for reducing limb shock/vibration?
That's why this is so much fun... more Qs than As.
I've got 3 bows to play with so I can compare them and then re-work the worst.
Theoretically I should home in on a best combination  ;D... but I'll probably end up with them improved to the point of uselessness  >:D
Used to have an acronym in electronics MBR ..... mended beyond repair  ;D
Del
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Offline Hawkdancer

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Re: ELB Musings
« Reply #3 on: April 30, 2019, 10:00:21 am »
I think the "w'ist whack" would get your attention fairly quickly, but I've only been shooting about 70 years! >:D (lol).  I do like my brace height (fistmele) to clear my fletching, generally use 5" fletching, and my fistmele is about 5.5", when I can get my thumb up straight.  On the other hand "Mbr" is not quite as bad as "fubar"(f.u. Beyond all recognition)! >:D.!
Hawkdancer
Life is far too serious to be taken that way!
Jerry

Offline Badger

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Re: ELB Musings
« Reply #4 on: April 30, 2019, 02:07:38 pm »
  Del I think the small gains that might come with a low brace height can be easily recovered with giving top priority to clean arrow flight right out of the bow. This seems to trump almost everything else.

Offline Del the cat

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Re: ELB Musings
« Reply #5 on: April 30, 2019, 02:23:05 pm »
  Del I think the small gains that might come with a low brace height can be easily recovered with giving top priority to clean arrow flight right out of the bow. This seems to trump almost everything else.
That's sort of what I was thinking, but I wondered if I could cheat it:-
Take a bow braced at 6". If a 1" block is fixed to the belly of the grip, the actual brace height in terms of the stress and curve of the bow hasn't changed (although by conventional measurements it is now 5").
But... one could use a 1" shorter arrow, and correspondingly lighter/dynamically stiffer arrow (at risk of wrist slap) and if that 1" block is correctly shaped, it should hardly effect the flight from the bow.
I've tried to explain it better, does that make sense? Is it just smoke and mirrors or is there a potential gain?
Del
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Offline Badger

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Re: ELB Musings
« Reply #6 on: April 30, 2019, 03:11:45 pm »
At the u,s tournament that 1" block would not be allowed. We have to use our hand as a rest and it can't be pulled past the back of the bow.

Offline Selfbowman

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Re: ELB Musings
« Reply #7 on: April 30, 2019, 04:59:17 pm »
I am with you on shock Del. The one! I built had plenty. I think it's a matter of straightening the off tiller so you can move the hand where ever it's needed! To achieve proper tiller in a pinch. Remember this was designed for war and when the King said I need a thousand in to months. Tiller was important  of corse but maybe this gave them more lead way?? I am sure some one will correct me if I am wrong. And please do if need be. Arvin
Well I'll say!!  Osage is king!!

Offline Del the cat

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Re: ELB Musings
« Reply #8 on: April 30, 2019, 11:44:18 pm »
At the u,s tournament that 1" block would not be allowed. We have to use our hand as a rest and it can't be pulled past the back of the bow.
Hmmm, the difficulties of language :-[.... I'll draw a pic! ;D
The "block" is just a thickening of the handle.
In the pic you can see that with or without the orange block, the bow is actually drawn the same and the bracing stresses will be exactly the same.
The draw length, brace height and poundage will be exactly the same IF measured to the back..
But for flight shooting they will be measured to the belly.
With the addition of the thickened grip, a shorter arrow can be shot.
Del
PS. Can't be pulled past the back?... In uk you can pull it back as far as possible (e.g, just short of the belly) but no overdraw aid is allowed.
« Last Edit: April 30, 2019, 11:47:37 pm by Del the cat »
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Offline Badger

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Re: ELB Musings
« Reply #9 on: May 01, 2019, 02:53:41 am »
Del, You might be right about the back of the hand, my memory plays tricks on me now and then.

Offline Del the cat

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Re: ELB Musings
« Reply #10 on: May 01, 2019, 03:41:18 am »
Just tried some indoor test shots with an old rolled up duvet as an arrow catcher, worked great.
Impressively fast ;)  :o >:D
Del
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Offline willie

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Re: ELB Musings
« Reply #11 on: May 01, 2019, 03:19:56 pm »
if you are concerned that the bow will get too skinny, why not go shorter?

of course I know nothing of the old world warbow flight rules that constrain your design

Offline Del the cat

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Re: ELB Musings
« Reply #12 on: May 02, 2019, 12:00:04 am »
if you are concerned that the bow will get too skinny, why not go shorter?

of course I know nothing of the old world warbow flight rules that constrain your design
Yup, already there ... it's as short as the regulations allow (plus half inch for good luck ::) )
Del
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Offline avcase

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Re: ELB Musings
« Reply #13 on: May 09, 2019, 10:31:21 am »
Del,
Have you confirmed if the “regulations” will allow you to shoot the bow with the built up handle like you show in the picture?  I put the word regulations in quotes because when it comes to traditional bow types, there are the rules that were written down, then there seems to be a bunch of other unwritten rules that pop up as soon as you show your bow to the officials. ;)

Sorry if I am going off on a tangent. I have just developed a strong hatred for lazily written rules of competition. It makes it unfair to competitors because it opens the door to inconsistent enforcement.  Often, the rules say something like “must conform to the traditional shape of the English Longbow”, but I believe this assumes everyone has a common understanding of what this is should be. Unfortunately, there is no such thing as a common understanding of what traditional form is. I would like to see these rules tightened up.

Arvin had a similar question about a built up handle. It isn’t explicitly prohibited in the flight rules because it still meets the 5/8 ratio for minimum thickness to width ratio requirement.

Back to the question.  Yes, having a deeper handle can give you an overdraw effect, allowing you to shoot shorter and lighter arrows.  It also means you would be drawing the tip of the arrow further down the back of your hand. In effect, you are using the back of your hand like a Turkish sipur overdraw, except you don’t have the safety shield the sipur has.

Thanks,

Alan

Offline Del the cat

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Re: ELB Musings
« Reply #14 on: May 09, 2019, 11:39:03 am »
@ Avcase.
Yeah, I'm sure a bit of a riser would conform to ELB rules, as the Victorian longbows were like that with a longish grip section, the fade being known as "Buchans dips" after a well manufacturer of bows.
I take your point about it being more likely to stick the arrow into the base of my thumb tho.  :o
Del
PS. Result from my 50# Boo/Yew/Ipe  :)
« Last Edit: May 09, 2019, 12:02:09 pm by Del the cat »
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