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Main Boards => PowWow => Topic started by: sendero25 on September 04, 2011, 06:21:00 PM

Title: Measuring recurve bow length.
Post by: sendero25 on September 04, 2011, 06:21:00 PM
I have an old Bear 76er that doesn't have the amo length printed on it or the length was on a decal that has fallen off over time.  My question is how do I measure the length of the bow so I can get a new string?  Do I lay a tape on the limb and measure around the curve of the limb nock to nock?  Or do I measure a straight line?  Or, if anyone knows, were all 76ers the same length and if so what length string do I need?  Thanks in advance.
John
Title: Re: Measuring recurve bow length.
Post by: Charlie Lamb on September 05, 2011, 08:36:00 AM
Measure along the back of the bow from nock to nock.  Most bows have an even number length...58-60-62-etc.
Your measurement should be close to one of those.
Title: Re: Measuring recurve bow length.
Post by: JimB on September 05, 2011, 10:03:00 AM
From one nock,over the curve,straight across to the other curve and follow that curve to the nock.If strings are listed by their actual string length,get one 4" shorter than your unstrung bow measurement.
Title: Re: Measuring recurve bow length.
Post by: Night Wing on September 05, 2011, 11:07:00 AM
Maybe the info in this link might help.

 http://www.archeryhistory.com/recurves/pics/bear54.jpg
Title: Re: Measuring recurve bow length.
Post by: Walt Francis on September 05, 2011, 02:46:00 PM
I was taught the same method as Charlie: measure along the back of the bow.   I found this drawing that depicts the method he described:
 (http://i3.photobucket.com/albums/y91/Slivershooter/measurerecurve.gif)

When using this method the length of the string should be close to 4" shorter than your measurement.

In 2000 the AMO changed to the ATM (or something like that) and they changed their measuring system, calling for the string to be 3" shorter than your measurement.  I haven't been able to find anything that justified the change unless they adopted the measuring method described by JimB; which on average reduces your measurement by approximately 1".  
As clear as mud?  
Many of the custom bowyers still measure their bows using the old method.  If your bow was built after 2000 your best chance of getting the correct length string is to contact the maker of your bow or measure the one on your bow (at the correct brace height) and have one of the string making sponsors here on Tradgang make you some.
Title: Re: Measuring recurve bow length.
Post by: Kituwa on September 05, 2011, 04:54:00 PM
I read the whole world wide web and could not find this,lol, thank you!
Title: Re: Measuring recurve bow length.
Post by: Keefer on September 05, 2011, 05:46:00 PM
Walt,
  That's not the back but is the correct way to measure a string...That is the "Face/Belly" side and the back is the opposite side....Not being sarcastic guys but we must teach a newcomer the right term...   :goldtooth:
Title: Re: Measuring recurve bow length.
Post by: Don Stokes on September 05, 2011, 09:16:00 PM
The back is the front and the face is the belly. Clear?   :)
Title: Re: Measuring recurve bow length.
Post by: Zbone on September 05, 2011, 09:30:00 PM
Yeah, Walt's diagram depicts the belly side of the bow.

The "back" faces away from the shooter, as the belly faces towards the archer.

Think of the back when you see snakeskin "backed" bows.

I was taught around 4" shorter string length nock to nock for recurves, and around  3" shorter string length nock to nock for longbows to begin, and that is while measuring along the "back" of the bow.

Keep in mind bows with proper brace height (fistmele) per shooter can be different, so string lengths will be different.
Title: Re: Measuring recurve bow length.
Post by: legends1 on September 06, 2011, 01:16:00 AM
Charlie is right ,its the back of the bow.not as shown on the belly.
Title: Re: Measuring recurve bow length.
Post by: Keefer on September 06, 2011, 05:47:00 AM
Mike,
 Now I may be wrong? I was always shown to measure the way Mr.Walt shows us in his diagram  :confused:  Maybe I need a lesson on the proper measureing of how to measure the string on the bow...  :dunno:
Title: Re: Measuring recurve bow length.
Post by: Ruby on June 02, 2016, 11:09:00 AM
I just started in January down the trad road but heard the same 3 inches on longbow 4 inches on recurve. I heard that is a rule of thumb starting point and measuring nock to nock with a tailors tape is more accurate. If you buy from an experienced string maker they have helped get me right for my recurves also. Im a newbie but have asked the same ? Hope this helps.
Title: Re: Measuring recurve bow length.
Post by: TOEJAMMER on June 02, 2016, 03:08:00 PM
I have always heard Walt's method of measurement.
Title: Re: Measuring recurve bow length.
Post by: Orion on June 02, 2016, 03:39:00 PM
A lot of recurve bows have a lot more shaping/protrusions of the riser/grip area on the belly side of the bow which could throw the measurement off, at least more so than measuring along the back of the bow. ( The pix illustrates that a little, but in fact, the line would follow the contours of the riser). That's why it's important to measure along the back of the bow, as Charlie suggests.

There's obviously a lot of confusion on this though, in part, because folks also often confound back with the belly of the bow.

Sort of like measuring draw length.  There are enough of us who do it differently that it's wise to determine how the other person is doing it if we want to be comparing apples to apples.

And knowing the bow length still only gets one in the ballpark re string length.  The AMO standard is a string 3 inches less than the bow length, regardless whether it's a recurve or longbow. Of course, the old rule of thumb is 3 inches shorter for a longbow, 4 inches shorter for a recurve. But, depending on bow design, and how the bowyer measures bow length, neither of those may be spot on either, but they should get you in the ball park.
Title: Re: Measuring recurve bow length.
Post by: damascusdave on June 02, 2016, 04:08:00 PM
Since you want to get a new string not make a new string what you need to do first is pick a stringmaker...I would recommend Chad Weaver of Champion Bowstrings...then simply contact Chad and ask him what sort of information he needs about the bow

DDave
Title: Re: Measuring recurve bow length.
Post by: M60gunner on June 02, 2016, 07:10:00 PM
X2 about Chad. He has made me my last 2 strings. Both bows I measured along the belly like in diagram. The last string was dead on bow makes BH recommended number and it has not changed. He used BCY X. Just to make it more confusing, if your limbs have a lot of "hook" in them the standard 4" rule may not work. I am referring to the new style limbs like 3Rivers is offering for their DAS recurves.
Title: Re: Measuring recurve bow length.
Post by: Car54 on June 02, 2016, 09:13:00 PM
Quote
Originally posted by Don Stokes:
The back is the front and the face is the belly. Clear?    :)  
Crystal! LOL
Title: Re: Measuring recurve bow length.
Post by: Bowwild on June 03, 2016, 07:57:00 AM
To remember face vs back.

"The bow likes you, when you shoot it, it likes to be face to face."
Title: Re: Measuring recurve bow length.
Post by: LBR on June 03, 2016, 08:55:00 AM
Measure from the string groove to string groove, following the contour of the limbs, through the center of the riser.  That will get you close.

AMO/ATA bow length has always been 3" longer than the "string master" (steel cable) that put it at proper brace.  Been that way since it's inception in the late 50's or early 60's.  Lots of bows and bowyers don't follow it, for whatever reason.  Wish they would.  It would sure make life easier on their customers when it's time for a new string.
Title: Re: Measuring recurve bow length.
Post by: Dave Worden on June 08, 2016, 07:49:00 AM
As usual Chad's nailed it regarding 3", 4" AMO, and ATA.  Just to put a finer point on it.....the AMO length of a bow is, as Chad Says, 3" longer than the string master that properly braces the bow.  IT HAS NOTHING TO DO WITH THE MEASURED LENGTH OF THE BOW!  That's where people get confused between the 3" and 4" rule of thumb and AMO.  You are very unlikely to find the AMO length of a bow by measuring a bow.  And, as has been already mentioned, the best way to determine string length for an "unknown" bow is to try a few, adjusting brace height till the bow is quiet.
Title: Re: Measuring recurve bow length.
Post by: BAK on June 08, 2016, 09:29:00 AM
LBR nailed it.  String length is determined by what the correct brace height is when strung.  We use these other methods to approximate that.
Title: Re: Measuring recurve bow length.
Post by: Orion on June 08, 2016, 09:58:00 AM
"AMO bow length is 3 inches longer than the string master that properly braces the bow," is really saying the same thing as the more informal statement that the AMO standard is a string that's three inches shorter than the AMO bow length. It's assumed that that string length will give the proper brace height. Just the same statement in reverse.

The problem arises, as Chad has pointed out, in that the measurement hasn't been around for ever, and, more importantly, it is not universally followed.