While I was making my first bow it sure seemed heavier than the 51 pounds my new scale was reporting.  Sure enough, it measures 56 pounds on two different scales at my local archery shop.  How irritating.  When I first got the scale I measured my 50 pound Martin Vision and sure thought it said 50 on the nose.

The scale is a Pelouze Model 7810 that I bought through the well known bow building supplier.  A ten percent error is really unacceptable in this day and age.  Pelouze is going to get a pretty good earful.  I have used other Pelouze scales, mostly digital, at work and they certainly seem accurate.

Is there an adjustment screw for it? If so it just might need calibrating to a known weight.

Most scales need to be calibrated, knob on top or bottom?

I dont know how you guys can tell 5 pounds, especially when it is around 50 to 60 lbs.

Mike

It's pretty easy to tell 2 or 3 pounds, much less 5 or 6.... UNLESS you happen to be Arnold!
Just how big an ole boy are you, LOL....

A Martin bow is probably not a good one to use as a standard for a scale.  They are somewhat notorious for having a heavier draw weight than indicated on the bow.  I can tell you my tender right shoulder can tell the difference in 2 or 3#, especially once the draw weight gets above 48#.  If the difference is 5 or 6#, my shoulder screams at me!!        

Bill

I had a Martin Hunter that was marked 60# @28", but scaled at almost 66#'s.  Yours sounds about right, lol!

When I first got the scale I put my Martin Vision on it and it read 50lbs, as marked.  My set-up to pull it was a little crude but seemed OK.  I knew my new bow was heavier than the Martin.  Last night I measured the Martin at 44lbs. on my tiller set-up.  I measured my new bow at the shop with an Easton digital scale and a spring scale and they both said 56+ lbs.  When I got home my tiller set-up still said 51lbs.  I then measured my Gamemaster, that measured 49lbs. at the shop, and it was 43lbs with my scale.

There is only a zero adjustment knob on the scale that is not a calibration.  I peeked inside the scale to see how it is calibrated.  There is provision to move one end of the spring attachment to different coils in the spring to adjust the rate (like a spring rubber in a stock car).  I won't mess with the spring until I explore a replacement scale.

All is not lost, I know several gents who like 56# longbows.  I went to my local exotic wood supplier yesterday and bought some Osage, Bocote and Cocobolo so I can make another bow.  And another, and another, and another...  

Hey Kevin,  bring it this weekend. we will but it through the ringer.......

I have never had a bow yet that scaled to what it is marked....
   Either bowyers tend to put the weight you orderd on the bow regardless of what the actual weight was....Our every Bow scale in the world reads differant....

Martins have gotten tighter on the spec's.My Vision weigh 5# heavier then marked on my scale.My Savannah weighs 2# less then marked and my Bamboo Viper weighs 2# more then marked.Can your scale be calibrated.I have a Hanson scale and I give it + or - 2# for bows I measure.

Between myself and friends, I have access to four different scales, three of which are outfitters' spring scales. None have ever agreed! Not much better, in my limited experience (just two) with chronographs. This only matters to me with my homemade bows, as I tend to trust the few top-end custom trad bowyers I deal with, among which Martin is not in my case one. Dave

I haven't noticed my Hanson scale to be off but thats not saying it couldn't be.I've checked it a couple times long ago but really only use it for myself anyway

The only real way to know is to measure it with known standards not a marked bow unless ofcourse you know for sure that it was checked with known standards LOL

If I am serious about acurracy-LOL! I take two twenty pound dumbells and calibrate the scale prior to testing the bow. I have a pretty standard spring scale and you can't expect too much for whatever small amount they cost.
I get annoyed when a bowyer tells me 'well it tested 50# on one of my scales and 55 on the other one'!