flying wire tensiometer

Discussion in 'Pitts' started by akmetal, May 2, 2014.

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  1. May 2, 2014 #1

    akmetal

    akmetal

    akmetal

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    Hello,

    I am looking into buying a flying wire tensiometer. My instructor wants to sell his to me, it is from Aviat but it is over a decade old (still in the box barely used). He told me the new digital ones from Aviat are $1400!!! and offered me half price but I don't think his is digital.

    I have done some google searches and seen flying wire tensiometers for like $300. Is the non digital one from Aviat the cats meow or is it some serious hype and the cheaper ones are just fine.

    I mean this is the flying wires on my plane so I want it to be dead on and if the one from Aviat is the only one people trust then so be it but the cost is so extreme I wanted to get some second opinions before I plop down $700.
     
  2. May 2, 2014 #2

    PittsDriver68

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    The less expensive ones work just fine. There are other threads here describing the how to-s and the tolerances. There are lots of airplanes flying that have had their flying wire tension set with a fish scale. Spend the money on gas.

    Best of luck,

    Wes
     
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  3. May 2, 2014 #3

    jerr888

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    I think of the tensiometer, as a starting point, which may need adjustment after several G-loadings, and flight observation?
    My fish scale is easily calibrated by hanging a 50# barbell weight on it. When was the last time your torque wrench, or digital whatever, was calibrated?
     
  4. May 2, 2014 #4

    will moffitt

    will moffitt

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    This is an example of an approach I like. Simple. Why does everything have to be digital.

    will
     
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  5. May 2, 2014 #5

    MTChris

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    In my experience with all the new digital measuring tools (micrometers,calipers,levels etc) I find that I much prefer the old vernier tools and dial calipers etc. I even own one of the worlds most sensitive and precise levels ever made and it was made in 1945! Don't let all the hype fool you. I have since sold all my digital crap tools and wills tick with the tried and true ones I already own and like. Remember one thing and it applies to many applications : The best pilots in the world flew aircraft that were made using a slide rule and a pencil.
     
  6. May 2, 2014 #6

    PittsDriver68

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    A lot depends on what you will be doing with the airplane. If you walk around at a fly-in grabbing wires, you will find different tensions. If you walk around at the US National Aerobatic Championships grabbing wires, you will find more tension. There is a wide range of values that will work in general. As I have noted elsewhere, if you will be pulling or pushing a lot of G's, enough tension so that your wires do not flop around is a good thing. And the more stress you plan to put on your wires, the more closely together you likely want them set up.

    The guy that I know who earned the IAC National Advanced Championship ran 1100lbs on his S-1S. But then, a casual aerobat could likely do fine with 750.

    Best of luck,

    Wes
     
  7. May 2, 2014 #7

    Lotahp1

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    Then there's airplanes like the Starduster Too that never had and numbers for the builders to use durring rigging. Basically rig it where the wings are straight and tighten them. Go fly and if any vibrate tighten them. That's the basic idea I get...I have not done my SD2 yet. I'd sure like a min and max number so one could at least verify it is in the safe range for a SD2 ( its a plus 6 minus 6 airplane at 1704lbs). As the gross goes up the g rating goes down. But still a plane alot of folks pull plus 4ish minus 2-3ish G loads in. Is there a good min and max one could apply to the rigging of a Starduster Too?


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  8. May 2, 2014 #8

    akmetal

    akmetal

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    Does anyone know what the differences are between say the aviat ones and the holloway ones. Are the aviat ones for people doing extreme competition. Even then the best a Pitts s2b will do is advanced and you risk stressing the air frame.

    Are they just setting an outrageous price and waiting for someone to bite or is there some reason for it?


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  9. May 2, 2014 #9

    akmetal

    akmetal

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    I get the 6th sense that in aviation everyone thinks that because you bought the equivalent to a 400k home means you should just fork over $100 a shingle for a roof.


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  10. May 2, 2014 #10

    PittsDriver68

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    Aviat may only sell one of those tools every couple of years and the price reflects that level of volume. They may not even stock that tool but just have their vendor drop ship.

    Aviat may resell a really gold plated tool.

    I suspect that the only individual who can answer that question is Stuart Horn.

    As for the price of aircraft parts, the high volume parts like bolts have prices that reflect the economies of making a lot of that item. The low volume parts reflect that those parts are made in lots of one or two and there are no economies in labor, materials, or equipment to be taken advantage of. Its not rocket science and no aircraft company is sitting on piles of cash. If you look at the labor that you put into building your machine, say 2500 hours, and pay yourself $30/hr for your skilled labor plus benefits, instead of working for free, you will calculate that your $35,000 biplane really cost over $100K....

    Best of luck,

    Wes
     
    Last edited: May 2, 2014
  11. May 3, 2014 #11

    Skybolt31

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    I have an Aviat tool, but it is not digital, not sure how you would do that. I bought mine many years ago and I think it was about $250, it was expensive at the time. I forked over the money because back then, there wasn't the internet and my access to so many knowledgeable people and alternate methods was nonexistent. I like the tool, but there are less expensive ways of measuring tension.

    It is basically a piece of flat stock with a roller on each end with a clamp in the middle. The clamp gets clamped to the wire and the flat stock bows, the amount of bow dependent on the tension in the wire. There is a pointer and a scale to tell you how much it has bowed. It is very well built and comes in a very nice wooden box, the snob appeal is awesome!
     
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  12. May 3, 2014 #12

    mbarker

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    Would love to see a picture of the Aviat tool. I have the Holloway tool.


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  13. May 3, 2014 #13

    taff

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    Flying wire tension meter.

    The only one I see in the ACS web is this:
    Part # 12-12500 (picture below)
    All the others listed (low and high costs) are cable tension meters.

    I don't know how you could use a cable tester to test a flying wire such as Bruntens, without causing a kink in the flat stainless steel wire?

    I am a long way to the task of stringing my Skybolt. But It would be interesting to see and understand how it's done, especially with a cable tester.

    The flying wire tester in the picture costs $240.00

    flying wire test.jpg
     
  14. May 4, 2014 #14

    akmetal

    akmetal

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    Hello Wes,

    I know what you mean about economies of scale. That's why my sight cost over 500$. I was not happy about that for some welded bars but it's nessecsry for solo acro.

    That being said it's my job as the consumer to get the best deal I can. I was not willing to weld up my own sight but for 1400 for the aviat tensioner I might look into seeing if I could make one or have one made. Luckily there is a cheaper option.

    That being said I just wanted to make sure that saving money does not result in doing something unsafe. I would rather pay more money for tso or stc and get quality but I think the heart of this tread as another poster pointed out is I don't want to pay for snob factor lol.


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  15. May 4, 2014 #15

    PittsDriver68

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    If I may ask, who supplied your wingtip sight? Is over $500 the current price for Dent-Air?

    I actually have a professional interest in the $$ as I am starting to make carbon fiber monoplane wingtip sights and I was told that Extra sells theirs for about $1000.

    Thanks!

    Wes
     
  16. May 4, 2014 #16

    akmetal

    akmetal

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    I will ask, my instructor has a Giles with one. I would love to build a carbon fiber plane but have to get some real estate and build a furnace big enough to cure a fusalage.


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  17. May 4, 2014 #17

    akmetal

    akmetal

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    Yes it was dent air, very professional great place to work with but the price was quite high.


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  18. May 4, 2014 #18

    TFF1

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    I think sometimes the prices are put there to make you run away. They have to offer them as support to the airplane but know that they dont want to stock them. I had to get some RR250 tools, so I called our RR parts supplier. $1400 for an injector wrench which is a metal plate with 1/4" of the top of a socket cutoff and welded on. They said they never has sold one... in 50 years of business. Aftermarket was $200. Most just use a socket, but my application had to have the wrench. The regional airline I worked for bought one set of factory tools and then had a machine shop dupe 7-8 sets for the same as the second set.
     
  19. May 5, 2014 #19

    Skybolt31

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    I am in Ohio now, will post some for you when I get back


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  20. May 5, 2014 #20

    Johnny White

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    The Holloway works on the same principle as all the other types. It is cheaper and as accurate as the torque wrench you use with it.
    I have rigged several Eagles and everyone of them had been rigged with a the fish scale method. All had loose wires. Loose wires will damage the spars (split them laterally) and drag / antidrag wire blocks if flown too loose. The flying wires on both Pitts and Eagles also serve to keep the wing from moving back during high speed compression loads which is how the drag wire blocks get damaged with loose wires.
    I use a digital tq wrench so that I can hit the value just before the anvil makes contact. A beam type works very well also. I don't use click type period.
    The tension is 750 to 950lbs. It is impossible to get them even but very close is good enough. Biggest pain is when one wire is one tension and the other mate wire is 100 or 150lbs different. you will have to loosen all the wires and turn the wire with the low figure 1/2 turn tighter to try and get them even. I go for the higher number on all the wires. Less flex from compression and G loads, much better Snaps and Aileron response. Take your time it is worth it!
     

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