First time bow, Help with measurements

[zaygone]

Hello!
Two years ago, I got hold of a nice nice piece of ash wood, for the purpose for making a longbow.
The stick is roughly 5x5 cm and around 2 meters long, along the (agelines?) of the tree.
I looked around trying to find the measurements of how to carve it.
I recently found it again, and reignited my interest, but this time I'll plead for help before I give up again.
The big showstopper is how to change the thickness along the bow. It get's thinner and thinner from the middle and out (duh), but I can't find anywhere explaining how much thinner.
Do anyone know, or know of somewhere I can learn more, about this?
Regards,
An aspiring Archer.

[Del the cat]

I'm assuming that by longbow you mean an English longbow?
The process is one of roughing out to approximate dimensions using bandsaw, axe, machete or whatever tools you have available.
You the see how it flexes and slowly remove more wood until you reach your desired draw weight and draw length.
There are several ways of tapering a bow.
1. A flat pyramid shape has virtually constant thickness and tapers in width.
2. An English longbow tapers a little in width and the thickness tapers at about 1.5 to 2mm every 6" for rough out... this should leave the tips a bit thick (say 15-20mm) the last 10" or so is then tapered further to about 1/2"
I make no apology for mixing metric and imperial as mm are v good for measuring thickness and width of bows but inches are good for length.

So your initial rough out dimensions depend on the required draw weight.
Assuming you want 60# or below you could rough out to 30mm square in the middle tapering to 20mm at the tips and then work from there.
The important thing to note is that virtually all tapering is done on the belly of the bow... the back is left as clean as possible.
If the belly has a problem the bow will take some permanent bend (set) or will shoot a bit slow... if the back has a problem it will explode.
Google bowyers diary where I blog up all my stuff including the failures... the search facility works quite well
Del

[Hawkdancer]

Say gone,
Welcome to PA!  I am a beginner,( or a newbie, as well),  you will get more replies I am sure.  Read several books:  "The Traditional Bowyer's Bible, Vols. 1-4", "The Bent Stick" by Paul Comstock, for longbows, I believe the title is "The Crooked Sticked", and several others!  A number of the folks here are very good at building longbows.  Ask lots of questions, take lots of pictures, and keep your cutting tools sharp.  Depending where you live, you may well be near another bowyer, watch, ask, listen, learn and have fun!  One of my favorite expressions is, "The only dumb question is the one you don't say!"  You will also find a pervasive sense of humor here.  The hobby is addicting!  By the way(btw), where are you?
Hawkdancer

[zaygone]

Hi again! Thanks for the answers, they really helped shape out the bow!
I've cut it as Del the cat described, and are in the process of bending it.
I have some questions tough that I couldn't find on your blog (however impressive that one is!)
1) What sort of string should I use?
2) How should I attach the string, I'm assuming cutting into the back is a bad idea.
3) Most importantly right now, how fast and how much should I increase the tension of the bending?
Right now I have it laying on a piece of wood, with the ends tied down and are slowly stacking pieces of wood up in the middle, essentially(though less sophisticated) doing the same thing as Del the cat has on his blog.

Sorry for the long delay, took me some time to get it done, being very careful^^

[Del the cat]

1.For the early stages you can use anything strong enough for a string. But commercial string material or linen make good strings.
2.https://bowyersdiary.blogspot.com/2012/03/filing-temporary-nocks.html
   https://bowyersdiary.blogspot.com/2012/11/temporary-nocks-and-string-line.html
3. Pull the bow to your full intended draw weight AS LONG AS THE BEND LOOKS EVEN.
Check out some of my Youtube vids....
Del

[lleroy]

look through the posts on this site a bit... there's something for everybody :-)

http://www.primitivearcher.com/smf/index.php?topic=20707.0
https://www.google.be/search?q=longbow+dimension+%2Bsite:primitivearcher.com&tbm=isch
http://www.primitivearcher.com/smf/index.php?topic=3895.0