Looking at options for test boxes.

Discussion in 'Armory - Q&A' started by ktinoue3, Jan 16, 2017.

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  1. dcchew

    dcchew Podium

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    Here are pictures of my 3 meter setup. The red push buttons are used to check the zero of each multimeter without having to having a patch cord sitting around. The 2 banana jacks on the bottom connect directly to the "B" meter (center meter) and can be used for the lame tester. The two stubby pins are for mask cords and the foil body cord alligator clip.

    The small hinges are used with small Bessey clamps to secure the test box to the table. Carpet tape or gaffer tape can also be used too.

    upload_2017-1-18_0-9-47.png upload_2017-1-18_0-10-15.png
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  2. brtech

    brtech Podium

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    Well, add the shipping. It is 20 ohm center scale.

    I really think you need shorts detection to test cords. You can do that with a switch, but just tying three multimeters to the A, B and C pins of "reel" and "fencer" won't do that. All of the meters discussed above are analog, which is needed to get intermittent break detection. Digital multimeters won't do that.
     
  3. dcchew

    dcchew Podium

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    Brian, if you got the time, please send me a sketch of the intermittent break detection wiring diagram and I'll try and include that feature into the next generation of the box. I'm trying to keep the enclosure size as small as possible for travel purposes. I think I've got enough room for 1 more set of switches.

    I have a Velleman analog meter that I was planning on using for lame testing. I found that it had too much damping in the meter movement for my taste. I went back to my Elenco M-1250.
     
  4. mtwieg2

    mtwieg2 DE Bracket

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    Well to be fair, there's no reason a handheld digital multimeter can't have a fast refresh rate, but unfortunately almost all models are locked to have a slow rate (which improves their precision). Most will have a continuity buzzer which has a fast response time, but that's not as good as an actual dial/graph with a fast response. High end models (like a fluke 115) do have an analog bar display with fast response, but I doubt most people are willing to shell out $150 each.
     
  5. neevel

    neevel Armorer

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    In addition to the analog bar, the other feature useful for detecting fast breaks is autoranging. On a fast break the meter will jump ranges, and that in combination with the fluctuations in the bar display will let you know what's going on. I have a Craftsman digital meter I was given as a gift years ago that retailed for about $70 that has both those features and works well. I'm full agreement that, if you are looking to spend anything less than that, you will want to go analog since you really aren't going to find anything digital with those features at that price point.

    Even with analog, it will take a little practice for the novice to discern the sort of wiggle in the needle that indicates a very short, but complete, break as opposed to a small fluctuation in the resistance.
     
    Last edited: Jan 20, 2017
  6. dcchew

    dcchew Podium

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    The intermittent breaks in a body cord are always hard to spot with an analog multimeter. When people ask me how to test body cords, I usually suggest that they use the little Favero tester and a pair of jumpers. The micro-break feature of the Favero tester makes it easier to spot the intermittent breaks. To measure the line resistance, use a multimeter.

    That's what makes the professional Favero tester great to use. When in the body cord test mode, the tester will spot intermittent breaks and measure the line resistance of all 3 lines at the same time.
     
  7. brtech

    brtech Podium

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    Unlike a weapon, it's VERY hard to get a body cord to have a really small intermittent contact. A fast analog meter will definitely twitch on anything you can do to a cord. Some meters are highly damped and won't do that, but I've never worried about catching intermittent cords on my analog meter testers. The 4 light Favero tester is very handy - I wouldn't armorer without it, but I find it more useful to find weapon intermittents, which can be much smaller. As always, YMMV.
     
  8. twisterfencing

    twisterfencing Podium

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    I am looking at the seed question from ktinoue3, what box?
    My suggestion that has already been made on this thread: make your own. Come up with your own ideas that will work for you. Make it yours! Know that part of the process of making your own test box gives you a large understanding of how it works, why it works and so on. I'm on about my 12th generation of different test boxes.
    You need to know how to short or jump a 6 position 2 pole switch to make a A-B short or a B-C short. We can all explain it to you until "we" are blue in the face, but until you do it and get it, we are spinning our wheels. Getting this knowledge only makes you better, not a box with step by step instructions in it or pre-made. Pre-made boxes are for us that know the why its made, just don't have the time to do it.
    Again: we have all "had" to go through it, we all had the same questions so we understand.
    I personally use the following test boxes:
    1. Daddy Dan Universal 3 meter box - I own two of them
    2. Daddy Dan Universal 1 meter box - I own one of them
    3. Twister Test Box: out of 75 of them I made for sale, I have 2 of them left that are "mine"
    4. About 11 different versions of test boxes that I keep working on them to make them better.
    5. Favero Professional Test Box
    Never rest the mind!
    Note: I do this for a living; not a once a month or twice a year thing!

    My favorite testing set up: Mathew Porter's piece of wood test strip with a C clamp, keep it simple!

    Start out by figuring out what you want it to do, knowing its gonna grow, then find a box or system you want and get busy!

    Also: noticed that you (ktinoue3) have only responded once on this thread. You shy?

    Gary Spruill
     
    Last edited: Jan 20, 2017
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  9. twisterfencing

    twisterfencing Podium

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    dcchew:

    Good job!
    Simple, easy to see and understand, well organized!

    Question: do you have it set up to test a weapon (foil or epee)? B-C or A-B short?

    Gary Spruill


     
  10. neevel

    neevel Armorer

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    Matthew's set up is cool- the rat-rod of test rigs (and the bonus of watching Dan's reaction whenever he sees it )

    Dan's testers are the Mercedes W126 of testers: old school, built to a standard and not to a price, and sadly not being produced anymore.
     
    Last edited: Jan 20, 2017
  11. twisterfencing

    twisterfencing Podium

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    I call Matthew's version: new style steampunk! (I hear you laughing)

    Daddy Dan's box: yes I know. I made Dan a promise years ago, like 12 or more years ago, I would never personally use a different box while he was still on this planet. When I go to meets, the biggest problem I have with my Universal boxes are that the guys know the cases they are in and just take them and they end up on their repair table. They love it because each one has its own octopus in it, shim and test weight. I have to push one of them over at a repair table just to "test" something myself. At the last meet we were at (Columbus), I went to Radio Shack and bought a ton of batteries and made/asked/requested that they swap all of them out. Note: these test boxes has a "ton" of batteries in them. There is like (9) 9V and 6 D cell each. Glad they last for years before having to replace them.

     
  12. neevel

    neevel Armorer

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    The thought occurs: The first person to build a fencing equipment tester that uses a Nixie tube display will win the Internet for a week. #hipster #armorer
     
  13. twisterfencing

    twisterfencing Podium

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    Here you go guys: you now have your assignment, get busy, here is where you can find some good quality Nixie Tubes: click here
    They only run about $145 each tube. :) How far you want it to drill down??
    For those that do not know me, I am joking about this. I don't want some young armorer going out and saying: well Gary said!;)
     
  14. dcchew

    dcchew Podium

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    Hey Gary. This box is only for testing body cords. I don't have a A-C or A-B shorting switches built in. Maybe I'll incorporate that feature into the next generation version.

    However, I do have a another box design that uses a single multimeter that will have a rotary switch setup that will test both a weapon or a body cord. It's about 1/2 finished. Too many other things that have to get done beforehand.
     
  15. Purple Fencer

    Purple Fencer Podium

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    I'm actually working on my own 3 meter box. Not by myself -- as my design-fu is weak -- but in concert with one of my clients. I'll be sending her this thread so she can see other thoughts.
     
  16. K O'N

    K O'N Podium

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    I want to make a 3 meter epee-only box to test weapons and body cords quickly. So I think I need a 3 position switch, right? Setting 1 is A-A B-B C-C, setting 2 is A-C B-C, setting 3 is A-B. Set it on 1 to test a body cord working, then flip to 2 and 3 to test for cross connection. Set it on 3 and plug a body cord in to test for a weapon working, then 2 to test for grounding.

    Am I missing anything? I don't care about foil and saber, but is there anything else an epee box should do?
     
  17. SJCFU#2

    SJCFU#2 Podium

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    Seems like you may be making it more difficult than it needs to be.

    When I build a three-meter box, I wire in a couple of LED's to check for A-B and B-C shorts at the same time as the meters check the A-A, B-B and C-C resistance, similar to Brtech's tournatest box (I don't bother with the A-C short since that would be extremely unlikely, at least not without one of the other shorts showing up first).

    I then add a separate socket set up for pluging in the body cord used for weapons testing - I find having separate sockets makes it easier to switch between the two functions. I don't really like switches (or any other moving parts, for that matter) so I try to keep them to a minimum. Currently the only switch I include is a standard DP/DT slide switch which disconnects the A and C line from the weapons test socket (otherwise it can set up a short which would allow a body cord with the A and C lines reversed at one end to register as good - something which seems unlikely, if only because it would make itself known as soon as you try to actually use it). The DP/DT switch is much less expensive and easier to find than a 3P/DT switch which you're proposing and shouldn't need to be cycled anywhere near so frequently as it sounds like would be necessary when following your scheme.
     
  18. K O'N

    K O'N Podium

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    I agree that an A-C short in a body cord is unlikely. But I want the weapons testing mode to test for A-C and B-C shorts, and I don't see how your setup does that. Am I missing something?
     
  19. SJCFU#2

    SJCFU#2 Podium

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    An A-C short in the epee will show up as an B-C short whenever you press down on the tip and short A and B together (or course this assumes that the epee is functioning properly in the first place, but if it isn't than you have more than one problem).

    I also wonder if a single-meter box with a 6-position DP rotary switch might not be more suitable for your purposes (and certainly easier, more compact and less expensive to build) As others have already stated, the main advantage of multiple meters is speed of testing, and that's really only a concern when you are looking at a line extending the full length of a convention center and every person in that line needs to be checked before their event can start.
     
  20. K O'N

    K O'N Podium

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    Compactness is not really an issue, since it's never going to move off my bench. And while a single-meter box is cheaper, it's not easier to use. My main goal here is to get a club full of twelve and fourteen year olds to perform a rudimentary test on a bc or weapon before they put a tag on it and declare it broken.

    Anyway, I already have the meters:

    [​IMG]

    Should be very stylish! I'll post a pic when I'm done.
     

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