Author Topic: Are there General Bow dimension guidelines  (Read 10577 times)

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Offline Beacon Archer

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Are there General Bow dimension guidelines
« on: January 21, 2013, 02:35:02 pm »
Hello,

I'm building my first bow just to see what to do. In the process of doing so, I keep asking myself a simple question: How do I know what the dimensions should be?

Is there a dimension guidlines for building Flat bows of various poundage?

Lost and in the dark,
Greg

Offline Hrothgar

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Re: Are there General Bow dimension guidelines
« Reply #1 on: January 21, 2013, 02:52:21 pm »
Stemmler Archery Co. of the 1940s-1960s had a general guide for building flatbows per weight and type of wood. If you do an internet search you might be able to find it.

In general, if you're just starting out, a rough guide would be to make your bow a minimum of 68" long, 2" wide, 4" handle with 2" of fade into each limb. 3/4" thick at the fade and tapering to 1/2" at the tips. These dimension should put you in the ball park for a #50 at 28" draw white wood flat bow. You can tinker according to your needs as you tiller.
Hope this helps, Eric
" To be, or not to be"...decisions, decisions, decisions.

Offline Will H

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Re: Are there General Bow dimension guidelines
« Reply #2 on: January 21, 2013, 03:49:58 pm »
Depends, what wood are you using? What's your intended draw length? Also what poundage at that draw?
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Offline Slackbunny

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Re: Are there General Bow dimension guidelines
« Reply #3 on: January 21, 2013, 04:15:44 pm »
With a whitewood, I would start somewhere around 64-68 inches long. Build the handle around your hand size with fades a couple inches long. I would go with 1.75-2.00 inches wide at the fades tapering to 1/2 inches wide at the tip. As far as thickness goes, start with about a 3/4 inch thickness and then tiller it down to the proper bend and desired draw weight.

This is a good starting point. But if you are working with a natural stave you have to work around its own natural characteristics which may determine your length and width for you.

Offline SLIMBOB

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Re: Are there General Bow dimension guidelines
« Reply #4 on: January 21, 2013, 07:37:23 pm »
I'm gonna go a little different direction here.  By your question, regarding dimensions for different poundage's, my assumption is that you are looking for a shortcut to get to a certain limb thickness for a particular draw weight.  No reliable formula exists IMO.  You have to start thick and work your way down.  All species of wood are different, and differences are too varied within a species of wood for any number to be anything more than a starting point.  The difference in a limbs thickness for a 55# bow and a 40# bow is very small.  It's mostly about feel at a certain point.  That comes with experience.  No shortcuts.
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Offline Beacon Archer

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Re: Are there General Bow dimension guidelines
« Reply #5 on: January 21, 2013, 10:01:21 pm »
Thanks for the information. I just have no clue as to where to start dimension wise. I see from what your writing, that it is something you cannot really plan but have to work to.

For my first bow I'm using Red Oak (only wood I could find at HD in my area). I would like to make it for a kid, so 20# draw max (Draw length is another question, is there a "child" standard?). I just have no clue if I can make it a 60" bow, how wide and thick it must be at that height, best distance to start the fades etc.

I can see I will have to just build it and go from there with the experience gained.


Offline steve b.

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Re: Are there General Bow dimension guidelines
« Reply #6 on: January 21, 2013, 10:34:04 pm »
I would say, if you have no clue, then you should read first.  Read traditional bowyers bible vol. I.  Not the whole book, just the chapter that pertain to your agenda.
« Last Edit: January 22, 2013, 01:22:51 am by steve b. »

Offline Beacon Archer

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Re: Are there General Bow dimension guidelines
« Reply #7 on: January 22, 2013, 01:21:26 am »
Steve,

I have all four volumes of the Bowyers Bible (almost finished volume 1, very dry reading and much of it is over my head at this stage), Several DVD's, bookmarked websites,etc. They do not give "general" dimensions. When I say I have "no clue", I mean I have no clue if I'm on the right track to make the bow the proper dimensions for the poundage I want.

No where can I find out if the thickness of the bow is different for a 50# bow as compared to a 20# bow, and if so, by how much? That is the type of question I'm asking myself and I'm unable to find any answers. So i figure I'm just gonna have to build them and answer the question myself.

Offline steve b.

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Re: Are there General Bow dimension guidelines
« Reply #8 on: January 22, 2013, 01:31:46 am »
In TBB vol 1 there are general dimensions, but not to the detail that you want.   The reason that is, is because every piece of wood is different.  So if you cut down two oak trees that are growing side by side and do everything the same in harvesting identical staves from each tree and make identical bows, they will be different, either in performance, shape, or quality.
So the general dimension thing only goes so far. 
I know what you want to do.. I would suggest you build some basic bows first and then when you "get it down", make a bow of the specs that you want.  By 'basic', I mean average size (not a shorty, no a longy), no backing, no snaky, no big knots, etc.  Whitewood or osage are good beginners.  Go for a large bow.  When successful, start scaling THAT bow down to the one  you want for this person.  Shorten it, thin it, narrow it, little by little, whilst checking tiller and weight, until its where you want.
That's one way to get to your bow.  OR, like I said, build a few that are successful, regardless of size and shape, then make the one you want.

sb

Offline rossfactor

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Re: Are there General Bow dimension guidelines
« Reply #9 on: January 22, 2013, 01:44:54 am »
The amount of limb thickness that separates a 50lb from a 30lb bow ain't much.  And it varies between different kinds of wood.  But you can always stay on the right track by frequently floor tillering, bending, and excersizing the bow on a tillering tree.  Once you've done this with several staves you start to get the hang of it. 

Bottom line is, you need to make some woodchips.  Chances are #1 may not turn out, but you learn everytime.  By number 3 you are miles away from where you started; by number 30 you feel like you've really got the hang of it; and somewhere around number 100 and something you realize that you actually don't know a damn thing about bow making  ;) And you'll need to make a few hundred more to really get the hang of it.

Gabe
Humboldt County CA.

Offline Beacon Archer

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Re: Are there General Bow dimension guidelines
« Reply #10 on: January 22, 2013, 02:12:29 am »
Steve,

I don't want details. Just a ball park figure for me to use as a base to start from. I understand that each wood is different, even if they are from the same cuts. I'm making this puppy on blind faith. I'm not to big on faith, I like to know what I'm doing and how to get from point A to B in detail. Which Bow building is not. I understand this. Bow making is more art then science. It can't be written down in exact moves. I understand, I just was looking for something to let me know if I'm on the right path on this build.

Rossfactor,
Thanks, I sort of figured that I will need to build a bunch (doesn't bother me, happy to do it). But as you know from experience, at first you are lost and unsure of yourself: asking yourself "am I doing this right", "am I missing something", etc.

BTW, I just started to tiller tonight. Very interesting aspect.

Offline bubby

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Re: Are there General Bow dimension guidelines
« Reply #11 on: January 22, 2013, 02:46:43 am »
so your building a red oak board bow for a kid, how old, and you started tillering so what numbers did you come up with, length width at fades, stiff handle or bendy, all this info is needed if ya'll want some help, Bub
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline osage outlaw

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Re: Are there General Bow dimension guidelines
« Reply #12 on: January 22, 2013, 02:55:26 am »
When I first started I was worried about exact limb width, thickness, and length.  The more bows I build the less I worry about it.  I rough the bow out a little extra in each direction, enough to know that it won't bend at all when pushing it on the floor.  Then I take my ferriors rasp out and start evening everything up and thinning it down.  When I marked the limb thickness on the last bow I built I didn't even measure.  I pinched the pencil just right and ran it down the bow limbs.  I guess what I'm trying to say is just go with it.  If your first bow breaks or ends up light, welcome to the club.  My first one came in 20 lbs under target weight. 

There are so many variables when it comes to selfbows its hard to predict exact measurements.  Just start off with more wood than you need and keep removing it until you have a bow.   
I started out with nothin' and I still got most of it left

blackhawk

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Re: Are there General Bow dimension guidelines
« Reply #13 on: January 22, 2013, 08:21:13 am »
With most normal proper designed bows of any wood(besides yew,or junipers) a good starting point is to make a 1/2" mark down from the back of the stave where your working limbs start,and make a 3/8" mark down from the back of the stave at your tips. Make these marks on both sides of each limb. Now grab a pencil and set it to where it is at the half inch mark using your finger tips to guide along the back of the stave so the line you draw will follow the contours of the back of your stave. Its called faceting a line...start at the half inch mark and try to slowly taper it to your 3/8" mark at your tips...do this on each side of each limb. This takes a lil practice,but its real easy to do on a board cus its dead flat straight. Now rough down to each line(but don't remove the line yet) at an angle creating a peak down the center of the belly of the limb...now flatten the peak down and start to round all your edges removing the line...all the while be feeling for an even thickness taper by running g your fingers down the thickness of your limbs. Remove wood at angles with any wood hand tool.  This will get you a floor bending stick ready for tiller with most any proper designed wood regardless of species for a normal hunting weight bow.

Offline Tom Leemans

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Re: Are there General Bow dimension guidelines
« Reply #14 on: January 22, 2013, 10:23:45 am »
Do you have a tillering gizmo? Tillering is the same basic process for any bow. As for thickness, that always depends on the width of the bow. The wider,the thinner. The narrower, the thicker. Get on over to bowyersedge.com and read some of Dean's articles for more insight and wisdom. CAUTION!: Dean is a literary master and you may need to re-read them several times before you fully understand.
;)