Author Topic: Next step  (Read 900 times)

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Offline sleek

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Re: Next step
« Reply #30 on: September 15, 2020, 04:03:59 pm »
I think that the deflex just allows you to use a bit of the brace height to actually send the arrow. The brace height of a deflexed bow is only about 2-3" if you get my drift. That means you get about 3-4" of draw length without straining the bow any/much more. But then you stress it more by putting in a bunch of reflex. I dunno but there seems to be a net gain in there somewhere. It's hard to think about because everything depends on everything else. :D

I've been putting notes together on this subject now for years. I used them all for a basis to build my bow that did so well for me in flight and broad head shooting. Your explanation of how deflex works is spot on. There is a point of diminished returns and I have been working for the last four years to find that point of balance. I started off with a 48 inch long self bow drawn to 26 inches, and went up in bow length from there. I found 48 to be too short for any practical use for me, and the early draw weight suffered greatly from the deflex it took to make the bow work. As a result,, to keep bow energy high, I went way high in draw weight. I however did not start experiments with reflex to up the early draw weight yet back then so perhaps you will find luck with that with your 48 inch bow.
« Last Edit: September 15, 2020, 04:17:39 pm by sleek »
Tread softly and carry a bent stick.

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Offline willie

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Re: Next step
« Reply #31 on: September 15, 2020, 04:25:11 pm »
.
Quote
To start, what difference does the radius make?

my only thought was about keeping the working limbs length proportional to the overall length if you were thinking to scale the existing design down.

Recurves were also killed off by borderline dogma in TTBB.

  The old statics of the past were generally not TOO short in length of lever.   
 
 It's the  deflex in the handle that's a bit of a change but fwiw I think a non deflexed has the potential to shoot faster, even if it's only for a few shots.   That's all that matters in flight though.

Pat, can you be more specific about which dogma you consider borderline?

Offline PatM

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Re: Next step
« Reply #32 on: September 15, 2020, 04:35:34 pm »
That recurving is  not so great because it overly strains wood and heavier tips could smother cast. Add to that  sinew being looked down upon for adding weight and decreasing cast.

 Yet people back in the day made sinewed  statics that pushed closer to 600 yards.

 Of course this was very likely done with parchment fletching and overdraws but it seems like we once again have a class that will  accept these things again.

Offline Selfbowman

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Re: Next step
« Reply #33 on: September 15, 2020, 07:37:33 pm »
DC the bow you sent did well. If I could build to the same workmanship I would use the same caul same length but wider for a fifty pound bow. Arvin
Well I'll say!!  Osage is king!!

Offline sleek

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Re: Next step
« Reply #34 on: September 15, 2020, 07:40:09 pm »
DC the bow you sent did well. If I could build to the same workmanship I would use the same caul same length but wider for a fifty pound bow. Arvin
Agreed
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline DC

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Re: Next step
« Reply #35 on: September 15, 2020, 08:39:23 pm »
Well, I did that. I made an almost identical bow but 25% wider. It's 50#@28". I dug a little deep toward one tip and got a bit of hinge. I glued a splint in. It was 4" long and maybe a millimetre(1/32") thick. Best joint I've ever made. It almost disappeared. I shot the bow and got shot shot after shot over 200, best was 204 I think. Just for kicks I shot my lightest arrow which is 305 grains. I got 238 fps. I've never shot any arrow that fast. I told Badger and he told me that the splint counted as a lam(which it does) and that bumps the bow up to Primitive Complex Composite. I'm going to try again after I finish this 35# shorty.
Vancouver Island
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Offline Selfbowman

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Re: Next step
« Reply #36 on: September 15, 2020, 09:15:54 pm »
That will get it done. Pretty sure. Arvin
Well I'll say!!  Osage is king!!

Offline Badger

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Re: Next step
« Reply #37 on: September 15, 2020, 10:40:55 pm »
Well, I did that. I made an almost identical bow but 25% wider. It's 50#@28". I dug a little deep toward one tip and got a bit of hinge. I glued a splint in. It was 4" long and maybe a millimetre(1/32") thick. Best joint I've ever made. It almost disappeared. I shot the bow and got shot shot after shot over 200, best was 204 I think. Just for kicks I shot my lightest arrow which is 305 grains. I got 238 fps. I've never shot any arrow that fast. I told Badger and he told me that the splint counted as a lam(which it does) and that bumps the bow up to Primitive Complex Composite. I'm going to try again after I finish this 35# shorty.

  Great speed and very efficient, I normally have to drop down to about 200 grains to get that speed.

Offline bownarra

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Re: Next step
« Reply #38 on: September 16, 2020, 12:09:34 am »
I forgot to mention the obvious stuff before.....
Shorter bending section concentrating the bend closer to the handle.
More energy storage  :)
Sinew and as before the shortest, sharpest recurves you can manage.
If you want it for flight don't deflex the handle. If you want it to last for thousands of shots deflex the handle a little :)

Offline DC

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Re: Next step
« Reply #39 on: September 16, 2020, 09:42:10 am »
Does sinew just count as a lam for flight?
Vancouver Island
If you don't have any questions you must not be paying attention.

Offline Badger

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Re: Next step
« Reply #40 on: September 16, 2020, 09:49:23 am »
Does sinew just count as a lam for flight?

  Yes sinew is counted as a lam, or just one additional material. 2 materials simple composite more than 2 is complex.

Offline DC

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Re: Next step
« Reply #41 on: September 16, 2020, 10:01:44 am »
I don't have a lot of sinew experience but that seems like an opening. Surely a sinew backed bow would out shoot a comparable hard backed bow, wouldn't it?
Vancouver Island
If you don't have any questions you must not be paying attention.

Offline bradsmith2010

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Re: Next step
« Reply #42 on: September 16, 2020, 10:39:41 am »
sinew backing is infinitely variable and interesting,, I think it would be a great skill for you to learn,, its never boring,, :NN

Offline PatM

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Re: Next step
« Reply #43 on: September 16, 2020, 11:41:44 am »
I don't have a lot of sinew experience but that seems like an opening. Surely a sinew backed bow would out shoot a comparable hard backed bow, wouldn't it?

 I would say yes.  The trade bow I made a few years ago was a "tri-lam"    It impressed me with its cast.

Offline bownarra

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Re: Next step
« Reply #44 on: September 17, 2020, 02:17:06 am »
The trick is making it 'work' enough.
Concetrating the bend closer to the handle will give a faster tip speed. Combine with the shortest sharpest recurves. Sinew heavily crowned and concentrated in the inner limb to help that area, start to feather it out about mid limb.
Sinew will (should!) allow you to start off with more intial reflex. The problem is overstraining the belly.....once it starts to take set the return speed goes...
I haven't been making any fun bows for too long all this flight shooting and performance talk is giving me the itch again haha
Good luck on your journey DC :)