Bow Length Formulas

[THoward]

Please share your thoughts on a formula for bow length.  I would like to hear if you have any general formulas that take some of the guess work out of the mix.  Please include the wood you worked with when your formula worked well.  I have worked Osage, vine maple and will be working hazelnut and black locust soon.

[snag]

I am a newbie at this first off. Hope others that are experienced chime in here...but I have read that you can double
your draw length and then add 2".  For instance your draw length is 28"X2=56"+2=58". 

[bigcountry]

I have always thought it was 2XDL+10% so mine would be 2X29.5"+5.9"=~65"  and from that some woods like BlackLocust a tad more and soem like hickory a tad less

[stiknstring]

I always heard that twice your drawlength for a bendy handle bow and twice your draw length plus the length of handle and fades for the nonbending handle bow as a general guideline

[Bent Rig]

For a stiff handled bow - I use for a minium your draw length x 2 + 4" for handle + 4" for both fades .

[Pappy]

What bent rig said is about what I do.Al tho I usually make them a little longer.That is
what I use as a minimum if I am building one for someone else.I usually over build most
of mine and have seen a lot here that make them a lot shorter.I have a 25/26 in draw
so 60 inches is pretty safe but make most 62/64 depending on the quality of the wood.
   Pappy

[THoward]

Thanks for all the feedback.  It looks like everyone is on a similar page.  I am going to a bowyers outing this weekend and hope to finish my vine maple and work on a hazelnut.  Thanks again.

[radius]

One thing that didn't come up is draw weight?  For Instance, If i wanted to make a 30# bow, could I shorten it quite a bit and make it a lot thinner/narrower?  Look at the warbows:  they were all very long, in order to accommodate their thickness...I think draw weight has to be considered as well.

[Kegan]

Draw length x 2 + 16"= Good minimum length. Almost all woods work- can't think of any that can't. Bows from 40-80+#. Bend the full legnth, though it works the same with stiff handle. Just narrow the tips for speed and cast.

I really like the longer bows. They make accuracy easier at longer ranges, and are alot easier to draw. I can pull my 80#, 70" hickory longbow with ease and comfort, and easily peg the center of the target at 30-40 yards. Since using these longbows, I haven't shot a shoter bow I liked.

[michbowguy]

this is a very "loaded" question.
every bow is different as is every wood has different properties.

the only "standard" i know of is the dredded AMO...."whatever lbs @ 28" of draw"

i bet you that 1 or maybe 2 people out of ten has an exact draw of 28 inches to even use the stupid "guidlines"

the real question should be..."what is the proper length of bow for the APROPRIATE DRAW LENGTH OF THE INDIVIDUAL?"

then there is a couple surefire ways of doing this.

i say if you dont have an answer for either of these scenerios you should start out with a bow that is just about as tall as the bowyer, and then he/she will have a better chance at making a shooter and learning how to go about making the next one better.

self bows are beautiful in the way that no two are alike,and no two woods act the same and even no two bows made from the same tree will act the same as well

sooo many factors are involved.

if you want to make a shooter, just overbuild one...and start reducing accordingly , without getting hingy or whiptillered.

most of all have fun , dont get a headache over it!
mbg

[Pappy]

Well said mbg,I have that problem all the time with folks that come out of the F#@$% bows.
Some it is just hard for them to get over.I usually start with a light bow and have them draw it
to where they usually shoot and measure them,most don't draw near what they think and a few
draw futher.It is important for you to know that before you start,that way you know what you are going for as far as weight and draw length,say I want 50@26 no real reed to tiller out to 28,you
are just bending wood that won't be bent again causing more set.I usuall take them an inch more than I plan for the bow.
  Pappy

[JackCrafty]

I guess I'm bass ackwards.  My formula = 50" long.  That's it.  (I make short bows) 

From there I look at the wood species, final draw weight,  and final draw length.  This will tell me the width.  I use The Bowyer's Bible formulas to help me with this (I didn't spend the $ fer nothin').

If I end up with a bow that is below draw weight, I spike it.

Simple. (I wish)

[shamus]

it depends on the style of bow and your design considerations.


My rules of thumb for selfbow length:
http://analogperiphery.blogspot.com/2008/06/selfbow-length.html