Welcome, Guest. Please Login
SLINGING.ORG
 
Home Help Search Login


Page Index Toggle Pages: 1
Send Topic Print
board bow Conundrum (Read 3452 times)
MammotHunter
Interfector Viris Spurii
*****
Offline


Give me a rock, a sling,
and give me some room

Posts: 1020
virginia, for now
Gender: male
board bow Conundrum
Aug 26th, 2006 at 11:25am
 
I've got a pretty strange problem and question for the bowyers here on the site. I recently started my second board bow (first one was absolute crap. I use it as a hearthboard now for the bow drill) and I've got it down to the dimensions I want that in theory, should produce a  bow of the proper draw weight (target DW is 50#). It's red oak, about 1.5" across at the centre, tapers down to 3/4" at the nocks, is 5/8" thick at the centre and fades down to 3/8" at the nocks. It's tillered nicely and I can string it with no problem, but I can only draw it back about 20 inches, and when I release, I get a hellacious slap on the forearm from the string. Right now the inside of my left arm is red, black and blue and is very warm. :\I was wondering A) what causes that nasty stinging bruise on my forearm and how do I correct it? b)Why can I string it but not draw it back to full draw, and C) would soaking it in water for some period bring the moisture content of the wood back up to the proper level, around 12-15% I think it is, and subsequently help me to be able to pull it back to full draw?  Any help you folks can give me would be much appreciated.
Back to top
 

Foolish is he who frets at night,&&And lies awake to worry'&&A weary man when morning comes,&&He finds all as bad as before&&-Excerpted from "The Havemal"
palaeoEvolution  
IP Logged
 
CanDo
Interfector Viris Spurii
Past Moderator
*****
Offline



Posts: 1652
New England, USA
Gender: male
Re: board bow Conundrum
Reply #1 - Aug 26th, 2006 at 12:57pm
 
What is the brace height (distance from handle to string when strung)? I know that my bow really tore up my wrist and forearm until I set the brace height to ~6". Otherwise, it's probably just a matter of technique.
Argh, I have much more to say, but must leave now. I should be able to fully answer in a few hours....
Back to top
 
WWW  
IP Logged
 
cipher20
Tiro
**
Offline



Posts: 43
NJ, USA
Gender: male
Re: board bow Conundrum
Reply #2 - Aug 26th, 2006 at 1:15pm
 
Why can you only draw it 20"?  Is it an issue of strength or does it pull 50# @ 20" and you don't want to draw past weight?  If the former, then you need to tiller down to a lower weight.  If the latter then you need to continue tillering it down until it bends well and you get your 50# at your desired draw length.  Remember, just because you can string it successfully doesn't mean that it is finished.

As for snapping on the wrist, that could be a couple things.  Like mentioned before, brace height should be around 6" give or take.  When strung does the string run directly down the center of the handle?  What type of handle are you using?  It might also be the way you are holding it.  When you grip the handle, make sure that your thumb knuckle is in the middle of the handle facing you as you draw.  If you just have large forearms, then you may just want to make or buy a nice stiff leather bracer.

Finally, never soak your bow.  There are a few reasons that you would do that, but not in this case.  Your profile says that you live in virginia so I don't think that your moisture content would be too low unless you store your bow in a hot box all the time.  The normal humidity will keep your bow at a high enough moisture content (perhaps too high even).

Back to top
 
 
IP Logged
 
MammotHunter
Interfector Viris Spurii
*****
Offline


Give me a rock, a sling,
and give me some room

Posts: 1020
virginia, for now
Gender: male
Re: board bow Conundrum
Reply #3 - Aug 26th, 2006 at 3:22pm
 
The brace height is 7 inches exactly. The string, as near I can tell, does run pretty true to the centre of the bow. People have said I have pretty large arms, so maybe this is part of it. The reason I asked about the moisture content was that, this being a board bow, the lumber is usually kiln dried to a final MC of about 5%, or so i seem to remember hearing and iirc, someone once told me the ideal moisture content of a bow is somewhere around 12-15%. There is no real handle on the bow. It's a cherokee style D-bow, so it's just got a thickened section about 4 inches long in the middle about 5/8" thick that bends slightly and then tapers outside of the 4 inch area to the nocks where it reaches the final thickness of 3/8".
Back to top
 

Foolish is he who frets at night,&&And lies awake to worry'&&A weary man when morning comes,&&He finds all as bad as before&&-Excerpted from "The Havemal"
palaeoEvolution  
IP Logged
 
cipher20
Tiro
**
Offline



Posts: 43
NJ, USA
Gender: male
Re: board bow Conundrum
Reply #4 - Aug 26th, 2006 at 7:55pm
 
I would say it is probably the way you are holding/shooting it. then.  Try shooting with your thumb in the position I suggested once you get the 20" problem solved and keep us updated on your progress. 

Also, Kiln dried wood will not stay at the very low moisture content that it comes out of the kiln with.  After a couple weeks it acclimates to the relative humidity of your area and will gain a couple %.  I used to live in AZ and had no problems with moisture content in the desert when using kiln dried boards.  And I would really suggest that if you do control you MC to any degree, 8% is about ideal from what I have seen.  I wouldn't bother though.
Back to top
 
 
IP Logged
 
Bikewer
Interfector Viris Spurii
*****
Offline


I love Slinging.org!

Posts: 1627
St. Louis, Mo
Gender: male
Re: board bow Conundrum
Reply #5 - Aug 27th, 2006 at 5:41pm
 
Are you using a bracer? 

I'm about to pull the trigger and start building my first bow.

I think I'm going with the "board" design after reading through a bunch of pages on the net and thinking about what tools I have available.

I was fairly enthusiastic about archery years ago, say mid-70s.  I had a very nice Herter's recurve that pulled 63 pounds, and could shoot it pretty well.
However, during my brief motocross racing career, I broke a small bone in my shoulder and was in such pain for about a year that I could not draw the bow at all. 

That was when the compound bows were just starting to come on the scene, and no doubt I could have continued using one of these, but they just did not appeal to me.
Still don't....
Nothing against technology, but I was raised up watching Richard Greene play Robin Hood on TV!
Back to top
 
 
IP Logged
 
MammotHunter
Interfector Viris Spurii
*****
Offline


Give me a rock, a sling,
and give me some room

Posts: 1020
virginia, for now
Gender: male
Re: board bow Conundrum
Reply #6 - Aug 27th, 2006 at 5:48pm
 
There really is something to be said about the purity and simplicity of the old ways, isn't there? I've shot a few bows, including a compound bow, but to be honest, it didn't feel "good" or "right" in any way. I set it down after a few shots and never picked up another one again. I was watching a bowhunting show on the television today, and every one of the hunters was using this huge, expensive, convoluted looking compound bow, some of which they said could fire an arrow at some ungodly range and speed. Not to demean their hunting prowess, but it looked shamefull. It looked to me like they had strayed too far from what archery was/should/used to be. So, I've decided to make my own bow and one day, all things going well, I'll get good enough to make one with which I can harvest my own food. And knowing I did it with my two hands will make that meat all the sweeter. I don't need a bow with so many gadgets on it that it can shoot the arrow and cook the meat itself. Seeing that show today, I was disgusted.
Back to top
 

Foolish is he who frets at night,&&And lies awake to worry'&&A weary man when morning comes,&&He finds all as bad as before&&-Excerpted from "The Havemal"
palaeoEvolution  
IP Logged
 
MammotHunter
Interfector Viris Spurii
*****
Offline


Give me a rock, a sling,
and give me some room

Posts: 1020
virginia, for now
Gender: male
Re: board bow Conundrum
Reply #7 - Aug 27th, 2006 at 5:50pm
 
I've got pretty large arms (think like a gorilla, maybe but less hairy) and pretty wide hands, too. I measured my arms the other day, and the thickest part of my forearm is about 2 inches smaller in diameter than the thickest part of my calf. My wrist alone is about 8.5 inches in diameter. So the fistmele, at 7 inches, is really just above the tip of my thumb, maybe 1/3 of an inch above or so. I was practicing shooting it yesterday, both with and without arrows nocked, and I managed to hit my arm less and less so I think that may be attributable to my poor technique. All the same, I'm going to try to fashion a bracer for my left arm out of leather or thick suede. Who knew archery could be so painful, but pleasant?
Back to top
 

Foolish is he who frets at night,&&And lies awake to worry'&&A weary man when morning comes,&&He finds all as bad as before&&-Excerpted from "The Havemal"
palaeoEvolution  
IP Logged
 
siguy
Interfector Viris Spurii
*****
Offline


si vis pacem para bellum

Posts: 1714
connecticut
Gender: male
Re: board bow Conundrum
Reply #8 - Aug 27th, 2006 at 7:02pm
 
just out of curiosity mammot hunter, are you arms incredibly out of proportion to the rest of your body, or are you a giant?
Back to top
 

if you want peace prepare for war&&&&my site
WWW  
IP Logged
 
CanDo
Interfector Viris Spurii
Past Moderator
*****
Offline



Posts: 1652
New England, USA
Gender: male
Re: board bow Conundrum
Reply #9 - Aug 27th, 2006 at 10:33pm
 
Quote:
I've got pretty large arms (think like a gorilla, maybe but less hairy) and pretty wide hands, too. I measured my arms the other day, and the thickest part of my forearm is about 2 inches smaller in diameter than the thickest part of my calf. My wrist alone is about 8.5 inches in diameter. So the fistmele, at 7 inches, is really just above the tip of my thumb, maybe 1/3 of an inch above or so. I was practicing shooting it yesterday, both with and without arrows nocked, and I managed to hit my arm less and less so I think that may be attributable to my poor technique. All the same, I'm going to try to fashion a bracer for my left arm out of leather or thick suede. Who knew archery could be so painful, but pleasant?



Wait, are you sure it's 8.5in diameter or in circumfrence!?!? Shocked Shocked

I'd be vary careful (would absolutely never) shoot my bow without arrows. It's called dryfiring, and I'm not sure if it can damage selfbows, but my dad's (fiberglass?) crossbow shattered when somebody did that.
Back to top
 
WWW  
IP Logged
 
cipher20
Tiro
**
Offline



Posts: 43
NJ, USA
Gender: male
Re: board bow Conundrum
Reply #10 - Aug 28th, 2006 at 12:28am
 
You should NEVER EVER dry fire a selfbow.  That is perhaps even more damaging to wood fibers than to fiberglass bows.  It can cause all sorts of mayhem that could lead up to a painful end to your bow.  You should take a magnifying glass and carefully examine your bow after dryfiring to ensure that no damage was done.  When wood bows blow they can send wood splinters and large pieces of the limb flying at extreme velocity.  Please be very careful as injuries sustained from that can be devastating.
Back to top
 
 
IP Logged
 
MammotHunter
Interfector Viris Spurii
*****
Offline


Give me a rock, a sling,
and give me some room

Posts: 1020
virginia, for now
Gender: male
Re: board bow Conundrum
Reply #11 - Aug 29th, 2006 at 11:37pm
 
And so it all came to an end today when the bow snapped on me as I was flexing it after a rather exhausting sanding and planing session. It wasn;t a terribly violent explosion, really, but the bow did snap on the diagonal across the midline of the thing and so, I was left with two, big triangular pieces of bow limb connected by a rawhide string. I was about to get upset, when I had an idea. Bows are really fun, and challenging, but they're also expensive (relatively), challenging (in a frustrating sense) and big. But what do you get with half a bow? An atlatl! my favourite weapon of all time. So, I've drawn up plans to make two new atlatls with the busted bow. I've neglected atlatls for a couple of years now. I came to this site an atlatl fanatic. actually, it was a search for atlatl plans that led me here, and it was partly my choice for my username, that I chose it because I loved to use atlatls, which were designed to hunt things like mammoths. I picked up the sling, trashed my atlatls to the side and threw out my darts. But I think this bow breaking was a good thing. I've gotten back to my beloved atlatls once more.  The MammotHunter is back, baby!
Back to top
 

Foolish is he who frets at night,&&And lies awake to worry'&&A weary man when morning comes,&&He finds all as bad as before&&-Excerpted from "The Havemal"
palaeoEvolution  
IP Logged
 
cipher20
Tiro
**
Offline



Posts: 43
NJ, USA
Gender: male
Re: board bow Conundrum
Reply #12 - Aug 29th, 2006 at 11:50pm
 
That's great that you are making the best out of a bad situation.  There's no reason you shouldn't try again though.  Constructing any weapon is a very satisfying process and bows are some of the toughest to get just right when you look at all the things that have to be just-so in order to maximize a design.  Once your new atlatls are finished you should try another boardbow or get ambitious and cut down a tree for staves.  I love seeing a new bow tillered perfectly and oiled to an exquisite finish.  It's a wonderful thing to gaze upon when you know that you did it yourself.

good luck and happy mammoth hunting!
Back to top
 
 
IP Logged
 
Page Index Toggle Pages: 1
Send Topic Print
(Moderators: Curious Aardvark, Masiakasaurus, Mauro Fiorentini, Bill Skinner, David Morningstar, Rat Man, Chris)