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Main Boards => PowWow => Topic started by: ken denton on May 21, 2010, 08:47:00 PM

Title: Ever wonder what # bow you are realy shooting?
Post by: ken denton on May 21, 2010, 08:47:00 PM
I notice a lot of bows in the classifed are being quoted as a different poundage than the bowyer has marked on the bow?
Could be a different scale being used than the type the bowyer used?
Arother factor is the bow string on the scale hook( which might mean it is pulling down the weight of the bow( say 1 1/2# for a longbow) before you start pulling it to record the #.
Another factor is to put the bow handle on the scale hook ( might mean a truer weight)?
If you know the real # of the bow you shoot best, then you know what # when you buy another? Ken
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Cyclic-Rivers on May 21, 2010, 08:48:00 PM
No, I just like to shoot.   :archer:
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: lpcjon2 on May 21, 2010, 08:50:00 PM
you lost me at "Could be".
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: BWD on May 21, 2010, 08:57:00 PM
Nope, maybe, I scale all of mine. If my scale is correct I know, if not, then maybe.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Whip on May 21, 2010, 09:31:00 PM
I can tell you that bows do vary considerably in measured weight on my scale from one bowyer to another, and even from one bow to the next with some.  I see a lot of different bows, and weigh them all on the same scale.  Even if my scale is not correct, I would expect to get consistently high or low readings.    

The majority of the bows I weigh actually come in less than they are marked.  Some by a pound or two, others by more.  Occasionally, but less frequently, my scale shows the same or slightly higher than what is marked.  I did have one older Bear recurve that was marked at 45# and my scale read 54#.  More commonly, a bow marked at lets say 55# will weigh in at 52 or 53#.  The inconsistency from one bow to another is suprising.

I did use a bag that was weighed at the local feed store to calibrate my scale.  Maybe my methodology is wrong by a bit, but it does weigh a know amount correctly.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: frank bullitt on May 21, 2010, 09:46:00 PM
Weights and Measures! I posted this problem awhile back. Folks who are having problems with arrow spine.

If your not sure of the weight that you are "Drawing", how can you be sure of the arrow spine?

Check and be sure, you need the numbers to add up!
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: ksbowman on May 21, 2010, 09:47:00 PM
I agree with Whip. Just because the bowyer has a certain weight marked on the bow it doesn't mean it is correct. I have a dozen bows and some are right on the money and some aren't. One is marked 60# @28 and actually weighs out at 64#.So without putting a bow on a scale and checking I wouldn't take it as written in stone.  Ben
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: 2treks on May 21, 2010, 10:02:00 PM
About a year ago I got a bow in for a reduction and refinish. It was 8# light on my scale. I took a dumbell and put it on my bath scale to check weight, and then checked my bow scale, it was right on. I repeated my checking and re-checking on 4 other scales and all where with in a pound of each other. I have since bought a digital scale and a certified weight. I seldom get a bow in for work that is marked what my scale reads. I have had two Bracks in this past month that weighed as marked. Most others are with in a pound or maybe two. Chuck
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Ken Taylor on May 21, 2010, 10:04:00 PM
Quite a while back I had a recurve that said 70# @ 28" and it was 75# at 28" no matter how I weighed it. At first I thought that I was measuring it wrong.

That's quite a difference but I guess percentage wise, it's not anymore than the others mentioned and in some cases even less.

My draw length with that bow was 31" (=  86#) so I had a bit of a hard time finding arrows back then.I ended up using aluminum 2419s.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Holm-Made on May 21, 2010, 10:28:00 PM
I have a guy that certifies local wrestling teams scales check my scales periodically.  I have 2 incase one wears out and goes bad.  Chad
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: James on laptop on May 22, 2010, 02:52:00 AM
It don't really matter to me as long as the bow is not too heavy.I don't even weigh bows I build.When they feel right,they are close enough.I only weigh a bow if wanting to test it with certain weight arrows and plan on posting about it or selling the bow.Other than that bow weight or arrow weight really just don't matter to me.  :)
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: vtmtnman on May 22, 2010, 06:06:00 AM
I've had high end stuff,cheap new bows and old Bear bows.I've never had a bow mismarked.Every bow I've ever scaled said what was marked on the bow...Be it at 28" or what it was supposed to be at 28".
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Tom on May 22, 2010, 06:17:00 AM
I"'ve had two well known bows mismarked. One was 3# light and the other was 3# heavy, when you draw over 28" it can make a difference.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 06:40:00 AM
imo, almost all bows are off in their marked drawing weight from their actual drawing weight.  lots of bowyers are still using inaccurate analog spring scales.  there's also the matter of drawn bow arrow length, which should be measured from the inside of the drawn string to the exact front of the riser/arrow shelf.

the real question is the accuracy and quality of the scale.

i've used a variety of quality spring scales over the decades, with ballpark results at best.  over the last few years i started using digital scales, with lots better results.  my latest is the easton digital bow scale, and that's proven extremely accurate when compared to post office digital scales.  

however, in the long run, 'ballpark' bow drawn weights are really good enuf for all of us shooters ... but maybe not bowyers, though.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: owlbait on May 22, 2010, 07:39:00 AM
Since most bowyers now guarantee weights plus or minus "X" pounds maybe it should say that also? I do know that a bow I was waiting on took longer because of new materials and the weight wasn't right so the bowyer explained to me and I waited a little longer. Some bowyers may say, close enough, and ship it, marked at the target weight?
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Doc Nock on May 22, 2010, 07:51:00 AM
I ordered one custom at 50#, promised to be +/- 3# of ordered draw.  It came in marked 54#. When questioned, was told if it doesn't work, he would take it down 3#.

Had it measured on 4 different bow scales and consistently drew 57#. Let me tell you...that much difference in weight for someone with shoulder issues anyway (arthritis), YOU KNOW IT!

Sent it back to reduce weight, made a few marks in the finish to tell, front and back of limbs and after 8 weeks, came back untouched and advertised to be 51#. Still was 57#.

That company isn't in business anymore.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: David Mitchell on May 22, 2010, 08:05:00 AM
Doc, I had the same problem with a bow that was actually 7# over marked weight.  The weight does seem to vary a lot among bows and bow makers.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 08:26:00 AM
QuoteOriginally posted by David Mitchell:
Doc, I had the same problem with a bow that was actually 7# over marked weight.  The weight does seem to vary a lot among bows and bow makers.
yeah, it's a two fold problem - hitting the expected weight/range, accurately measuring the drawn weight.

imho, at the very least all bowyers need to have and use the best digital scale available.  then the rest is up to their craftsmanship.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: wingnut on May 22, 2010, 08:45:00 AM
Rob,

Just for clarification.  Standard ATA/AMO drawlength and weight is measured at 26.25 inches from the pivot point of the riser.  Not the front edge of the bow.

Mike
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Apex Predator on May 22, 2010, 09:12:00 AM
Yep, measured from the deepest part of the grip 26 1/4" to the string for weighing one at 28" draw.  This normally is pretty close to 28" to the front of the shelf, but not always.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 09:21:00 AM
yep, i fully understand the amo 26.25" standard.  

however, most of us have always used the more practical clothespin-on-the-arrow-@-28" approach to measuring holding weight, and it's pretty much close enuf.    ;)
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: wingnut on May 22, 2010, 09:29:00 AM
Well the close enuf approach is probably what got this thread started.  If everyone measures them using a standard measurement for length and uses a quality scale, well then it should be all the same . .. right?

We have ours set up to measure at the standard with a top quality digital scale.

I know within a 1/10 of a pound what the weight is when the bow leaves here.

Mike
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 09:45:00 AM
mike,

a pound +/- ain't at all a big deal, and that's all the variance i've ever found between the amo 26.25" and front-of-riser 28" for most stickbows.  

what is a big deal is a marked bow weight that's 2# or more off a reality check.  that's what i reckon this thread is about.  but it's good to know yer one of the bowyers that does it all correctly, and with the right tools.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: wingnut on May 22, 2010, 10:11:00 AM
A good example of what can happen is a customer of ours had a Dryad Hunter bow for over a year and had shot it extensively.  She took it to a shop in town and had the owner weigh it.  He said it was 7# over the marked weight.  She called madder then a wet hen and I had her send the bow here.

When it arrived we strung it up and weighed it.  Exactly the weight that it left here and what was marked.

I called her back and asked how they weighed it and what scales were used.

She went back with a couple other bows she had.  They weighed 5# more the marked.

She asked if they calibrate the spring scale used.  Nope. .no reason too it's perfect.

Then when I asked how they measured drawlength it was to the front of the riser.  A hunter is about 1.25" at the pivot point.  So it was drawn to 28.5 AMO about 1.5-2 #.

Add it all up and the bow weighed 7 pound more on an uncalibrated scale measured to the wrong place.

That's why standards are important.

LOL

Mike
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 10:21:00 AM
QuoteOriginally posted by wingnut:
....  A hunter is a little about 1.25" at the arrow pass.  So it was drawn to 28.5 AMO about 1.5-2 #.  ...
dunno what ya meant by the above - with that bow, was the riser front end 1.25" past the pivot?

no matter what, sure sounds like the scale was the prime culprit ... as it is in almost all cases of incorrect bow weight markings.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Bowwild on May 22, 2010, 10:22:00 AM
I also replaced my standard spring scale with an Easton Digita Scale -- the same they use at international FITA tournaments to make sure archers' equipment is "legal".  I'll admit, I mostly do it for the "fun" of knowing. However, I think it is pretty important to know when buying, cutting, and tuning arrows. For folks who go to the trouble bare-shaft and other intricate methods of tuning actual draw weight is one of the starting points. I can't imagine anyone wanting to know exactly what components weigh that wouldn't first want to know their exact draw weight.

I also think bowyer's who charge extra for bows made to specific draw weights should use the most accurate measuring device as possible. I wouldn't appreciate paying $25-50 extra to get it exact and then finding the bow didn't spec out.

I have checked all my bows for draw weight vs. the documented (on the limb or riser) and found it common for the weight to be off 1-3 pounds. Nothing worse than that but I have only measured 9 recurves.  Of course if I was a longbow shooter and measured one of these contraptions (I'm only kidding here guys) I'd expect it to change draw weights based upon different moon phases and whether or not I was in rut. Sorry to you fellows who tell me from time to time to get some "limb straightener" for my recurves!
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: on May 22, 2010, 10:35:00 AM
Hanging the bow by the string does not give an inaccurate reading,  the weight of the bow  merely represents the draw length at that many pounds.  We have had one bowyer that I think was fudging to hit the target weight because we had bows that were both three pounds heavy and four pounds light.  One very popular longbow maker is consistently 2 or 3 pounds heavy than marked, that does not bother me at all it is consistent. I think that the difference between a single hook and something that the string fits on that represents  fingers may give a slight variation as well. A Bear dealer in the area showed me the difference once on his bow scale, not much but it was different.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: wingnut on May 22, 2010, 10:47:00 AM
Fixed it!  Dang I should proof read before I hit send.  LOL

Mike
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Bjorn on May 22, 2010, 12:19:00 PM
I make self bows for my own amusement, and use a spring scale hung from a nail to which a yard stick has also been attached.
I measured the DL using the ultra scientific clothes peg method and marked 28" on the yardstick.
The scale gets calibrated with a 40 lb dumbell that was weighed on my bathroom scale. Both are analog-not digital; but close enough for me.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 12:20:00 PM
the easton digital scale is pricey it's SO good - ain't nothing like it around that i've seen and glad i got me one.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: lpcjon2 on May 22, 2010, 12:22:00 PM
What ever happened to the old days and how they did things...LOL
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 12:28:00 PM
QuoteOriginally posted by lpcjon2:
What ever happened to the old days and how they did things...LOL
THESE are the good ol' dayze!    :laughing:
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: CaptJack on May 22, 2010, 12:51:00 PM
all the bowyers just put the string on the scale hook and pull the riser down to 28" at the front of the riser - it's how it's always been done

it was Bob Lee (Wing) that started the AMO
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Richie Nell on May 22, 2010, 01:24:00 PM
My bathroom scales show exactly what Roger wrote on my Widow recurve.  Either both right or both wrong.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 01:25:00 PM
QuoteOriginally posted by Richie Nell:
My bathroom scales show exactly what Roger wrote on my Widow recurve.  Either both right or both wrong.
bathroom scale!?  :jumper:
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Bowwild on May 22, 2010, 02:32:00 PM
I need to stand on the bathroom scales and see what I weigh when I draw my bow!  My bow is so good to me at other times maybe I'll weigh 10 pounds less when checking this "draw weight"? LOL
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Rob DiStefano on May 22, 2010, 02:52:00 PM
QuoteOriginally posted by Bowwild:
I need to stand on the bathroom scales and see what I weigh when I draw my bow!  My bow is so good to me at other times maybe I'll weigh 10 pounds less when checking this "draw weight"? LOL
:laughing:    :laughing:
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Red Beastmaster on May 22, 2010, 09:37:00 PM
I know a guy who tried to weigh his compound with a bathroom scale.

He set the scale on the edge of the kitchen table, hooked the string over the corner of the scale, got on his knees and pushed the bow down to full draw..................... Can you tell how this is going to end?

Right about the time wifey leaned in to read the scale the string slipped off the scale...............the bow dry fired, he slammed his bow to the floor mashing his fingers, wifey screams, the scale flips through the air and lands on the back of his head................then wifey starts beating on him for almost killing her! True story!
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Doc Nock on May 22, 2010, 10:15:00 PM
Red,

Is that one of those Beaver County stories I almost got to live with!  :scared:    :saywhat:
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: jcar315 on May 23, 2010, 12:37:00 AM
I don't have a scale but was working on some factory camo removal today and here is a 1969 Bear Kodiak Hunter marked at 60#

http://images.imagelinky.com/1274589088.jpg

After some elbow grease this is what was under the strike plate

http://images.imagelinky.com/1274589339.jpg

I have often wondered about this issue but don't have a scale. Usually don't remove too many strike plates on my Bear bows but it is always interesting to see what waits under them.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: Gil Verwey on May 23, 2010, 05:28:00 PM
Red Beastmaster I am picturing this and rolling on floor. I wish I was there to see it. Ha! Sounds like something I would do with my wife. I am not the sharpest knife in the draw either!

I did see a thread where someone made a board with a base and used the bathroom scale on the floor. That worked out well for him. I can't find the thread. Maybe thats a good thing. They don't let me play with sharp objects either.
Title: Re: Ever wonder what # bow you are realy shooting?
Post by: LBR on May 23, 2010, 05:40:00 PM
Chek-Mate uses a postal type scale that is calibrated to be within 2# @ 200# (or .5# @ 50#), and Marc does measure by AMO standards.  Close enough for me.

I have a non-Easton digital scale, and so far it's been on the  money.

Something I didn't see mentioned--you can change the draw weight of your bow slightly by raising or lowering the brace height.

I've had a few people over the last 10 years or so tell me that their bow wasn't marked correctly.  When I asked, the answer was always the same--a hanging spring type scale.  I always suggested they check on a calibrated bow scale.  Never had to send one back because the weight was off.

Chad