tension calibrator alternatives

Discussion in 'Stringing Techniques / Stringing Machines' started by ppt3, Aug 8, 2018.

  1. ppt3

    ppt3 New User

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    Seems many ppl use digital scale for tension calibration.

    Just wonder any particular ones you recommend?

    I searched a little bit, but found that many models do "lock" the reading after it stabilized. I am hoping to find one without locking feature, so I can keep monitoring the tension drawbacks.

    Thanks.
     
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  2. gmatheis

    gmatheis Hall of Fame

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    I use a cheap digital luggage scale (under $10 from Amazonia), I don't think it "locks" at least not right away.
     
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  3. jim e

    jim e Legend

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    The Decut bow scale has instant readout and a lock out readout for peak reading. So it can measure peak (highest reading) and continuous (instant) weight, depending how you set the scale, one button changes the mode.
    It was made for archery, and national archery judges use this to measure archery draw weight for national competitions, and compound bows have a peak draw weight and a let off draw weight and this measures both by either a fixed scale .My brother is an archery judge.
    Scale is sold on big auction site very reasonable. Around $50.00 for plastic one, but... I suggest a few $ more and get the metal one as it is very strudy over the plastic one.
    https://www.bing.com/images/search?view=detailV2&ccid=Brs7kv5g&id=BC9BFD61D7D0DD3C0A3B47C9E2981225456BABC2&thid=OIP.Brs7kv5gWFlX4EafpRzeUQHaE8&mediaurl=http://static1.shop033.com/resources/9D/157/picture/D0/86312912.jpg&exph=500&expw=750&q=decut+scale&simid=608044896281102411&selectedIndex=0
     
    Last edited: Aug 8, 2018
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  4. struggle

    struggle Hall of Fame

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    Would you mind taking a picture of how you rig that?

    I have two digital scales (with dead batteries) and a typical spring scale.

    Honestly, I've never calibrated my Wise. I should do that (go get batteries).
    I did use them on my lockout (eagnas 910) and they all varied abit, but the combo gave you a good idea of how to scratch your head.

    On all my rigs i use kevlar and try to minimize friction on the pull (i pull over a sharpie, seems slick enough...).
     
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  5. jim e

    jim e Legend

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    I just made 2 loops with 2 strings.Tie a big open loop on one end of scrap string and place loop around the handle of scale and loop the other end of that same string string through that tied open loop so string holds well to scale handle in middle of handle, as it is a hand held scale with other end to tension head, and other loop string from scale open clip, as it has a clip to hold string, to machine fixed clamp. Pull tension and read.This scale is designed to pull an archery bow string using your hand, so I just rigged up a string to hold in middle of handle, so scale is in middle with string on each end.
    \Basically I rig it with this.. scale has one string on one with the clip end going to fixed clamp, other string tied to handle going to tension head with scale in middle between the 2 strings.
    The scale is with my brother presently, as it is his scale.
    To be honest I don't even bother to check my stringing machine any more as it always pulled accurately when I did check it.
    The stringing machine I have goes through a calibration check on its own when I flip on the power switch, and I never had to calibrate it, and the few times I did check it with scale it was accurate.
     
    Last edited: Aug 8, 2018
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  6. struggle

    struggle Hall of Fame

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    word.
     
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  7. ppt3

    ppt3 New User

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    Thanks. That Decut bow scale is quite expensive. Any low cost option? I used my friend's gamma calibrator to test my stringer, it is about 2lb higher. I didn't bother to adjust, just minus about 2lb around 50.
     
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  8. kdm711

    kdm711 New User

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    I already had a digital scale that has a peak reading before I bought my Neos 1000. So I tried it and it worked fine. The one I have is made by American Weigh Scales (AWS) and the model number is PK-110. I paid $21 for it.
     
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  9. AndI

    AndI Rookie

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    Digital tennis calibrator made by Wise. Factory-calibrated (unlike fish scales). Quite inexpensive for what it is, at $65.

    It does not lock.
     
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  10. Irvin

    Irvin G.O.A.T.

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    I got a digital luggage scale with peak hold a few years back I found on the internet for about $12

    EDIT: There’s one like it on the auction site for $24 - $40 - Aws Pk-110 Peak Hold Digital Hanging Scale
     
    Last edited: Aug 10, 2018
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  11. R15

    R15 New User

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    For those who use luggage scales, why/how do you trust them to be effectively calibrated?

    Do you ever check them with a test weight?
     
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  12. Irvin

    Irvin G.O.A.T.

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    If you strung your racket and the tension was 2% off do you think you could tell? Federer sometimes varies his frames by a Kg or more and that’s about 4%.
     
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  13. R15

    R15 New User

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    The nature of tennis strings and the way they lose tension means low percentage point accuracy off the machine is probably not significant for the majority of 'real-world' players, but when many of us obsess about the details of stringing it seems inconsistent to set the baseline for a machine (i.e. the tension it pulls) by using something that is not intended for such use and appears to offer nothing to justify the confidence in it.

    I guess context of the machine being used and who you are stringing for is relevant...but I would still want to know something was reasonably accurate before re-setting something.

    Though of course for anyone not worried about inaccuracy why bother checking the calibration in the first place?

    Hey ho, maybe it's me who is worrying too much about the detail.
     
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  14. Irvin

    Irvin G.O.A.T.

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    @R15 Nothing wrong with checking accuracy, so I did. My bag weighs 3.2 lbs when I add 10.0 lbs of weight at a time up to 50 the weight of the bag increases 10 lbs at a time up to 53.2 lbs. There is a little bit of wobble as I get up in weight and the 1/10 & 1/100 digit bounces a bit. So I assume the scale is fairly accurate. I do check my machine every time I clean the clamps.

    EDIT: I'm a little on the OCD side myself at times.
     
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  15. esgee48

    esgee48 Legend

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    If you are OCD, you test the scale with known weights before using to check your machine. Peace of mind is priceless. :)
     
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  16. Irvin

    Irvin G.O.A.T.

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    LMAO I'm not going to buy 50# of known weight .

    EDIT: I guess I could take the weights I have to the gym and measure them on the balance scale.
     
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  17. Wes

    Wes Semi-Pro

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    Yeah... but then who's to say that the balance scale at the gym was calibrated?
    Now you're gonna have to take that gym scale and...

    Damn it!

    (The Devil made me do it. :p)
     
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  18. esgee48

    esgee48 Legend

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    1 gal of water is ~8.34 lb. 5 gal bucket holds 41.7 lb of water. So, if the empty bucket weighs 2 lbs, a bucket with 5 gal should weigh 43.7 lb. Use 2 5 gal buckets if you need to go higher. A measuring cup is useful for many things. After calibrating/measuring, use the water in your garden. My scale was off by about 0.4-0.5 lb linearly. So, now you have a cheap way to check your luggage scale before using it to check your tension head. As I said, some of us are OCD.
     
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  19. Wes

    Wes Semi-Pro

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    Yeah, but what if the measuring cup wasn't properly calibrated? :p
     
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  20. Herb

    Herb Rookie

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    Buy a calibrated test weight. I had a 50lb certified weight I paid about $40 for 30 years ago. Now it runs over $200. Shop around and see what you can get locally.
     
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