Author Topic: Width Vs String Follow  (Read 2231 times)

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PeteDavis

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Width Vs String Follow
« on: June 09, 2010, 10:43:40 pm »


I just tillered in a kit, red elm with a hickory back strip. Long bow, 1 5/8 wide and 67" ntn. I'll get some pics up when I get finished.

I glued this bow stave  up with 1.5" of reflex. As of tillering in, it now follows the string an equal amount.

Is is possible to reduce this follow, by narrowing the limbs and making them thicker to achieve equivalent weight? I am building these kits long and wide now, because it's easy and somewhat safe and stable. Will branch out on the next one.

PD


Offline Mark Anderson

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  • Mark Anderson Buckie, Scotland
Re: Width Vs String Follow
« Reply #1 on: June 09, 2010, 10:48:15 pm »
I am of the thought that thin and wide is the best way to keep string follow and set to a minimum so I think your original approach is best.
1.5" of string follow isn't bad at all. i think anything less than 2" is very acceptable. Maybe next time just introduce a bit more reflex to compensate.
JMO, other guys on here know WAY more than I do.
Mark
"Mommy some guys just don't know how to shoot REAL bows so they have to buy them, probably at Walmart and they have wheels on them."  Caedmon Anderson (4yrs)

PeteDavis

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Re: Width Vs String Follow
« Reply #2 on: June 10, 2010, 12:48:54 am »

Could you please explain trapping? This bow is just a tillered stave with string grooves. I have yet to glue a handle or final shape it.  There's enough weight to spare, if I decide to trap the edges. PD


Offline sailordad

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Re: Width Vs String Follow
« Reply #3 on: June 10, 2010, 01:01:56 am »
trapping= when the back is narrower than the belly,giving the bow a trapezoidial (sp? word?) cross section
               or it looks like a  trapezoid
i always wanted a harley,untill it became the "thing to ride"
i ride because i love to,not to be part of the crowd

Offline Badger

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Re: Width Vs String Follow
« Reply #4 on: June 10, 2010, 01:15:16 am »
     You may have higher than optimum moisture content where you live. 10% or more is bad for set. Also examine your tiller and see if you used up all the available limb for bending. I tend to crowd my tillers as I like stiff outer limbs and stiff out of the fades and pay the price sometimes. Is your set equal throughout the limb or concentrated in small areas? Steve

PeteDavis

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Re: Width Vs String Follow
« Reply #5 on: June 10, 2010, 01:53:32 am »


I kept the bend out of the handle mostly. Moisture is a real issue here, I live in Appalachia in a hollow with a creek.

Does elm get ansy with water??? I know hickory does. My backing strip is under 1/8th.

You guys are great!

PD


Offline Del the cat

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    • Derek Hutchison Native Wood Self Bows
Re: Width Vs String Follow
« Reply #6 on: June 10, 2010, 03:49:42 am »
Like the other guys sat it's the thickness that gives you set as there is more strain on the wood.
Wide is kinder to the timber.
A bit of set isn't really a problem, look upon it as 'conditioning' the belly.
even spring steel will take some set, ask the valve springs in your car.
If it doesn't have a little set then it's not working hard enough!
Del
Health warning, these posts may contain traces of nut.

Offline George Tsoukalas

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    • Traditional and Primitive Archers
Re: Width Vs String Follow
« Reply #7 on: June 10, 2010, 10:31:15 am »
To answer your question, no. For the record, you have 1.5 in of set and no string follow in your situation. At any rate the set is caused by the compression and subsequent collapse of the belly cells. The amount you have is quite acceptable and may make for sweet, smooth shooting bow. There is a way to mitigate set. Since it is caused by the collapse of belly cells in areas where the bow is bending you can reflex areas that are not. In most bows that's the handle area and the last 6 inches of each limb. That will work for a selfbow. Typically , most glues don't take well to heat so in your case I'd just love with it, Pete. 1.5 in is an excellent amount and indicates the design is adequate. :)  Jawge
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