Brake Line Standoffs

Discussion in 'Workshop Tips and Secrets / Tools' started by FritzW, Feb 28, 2017.

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  1. Feb 28, 2017 #1

    FritzW

    FritzW

    FritzW

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    Since just zip-tying the brake lines to the gear legs wasn't complicated enough for some members of our chapter Waiex build team I made some waaaaay overthought standoffs.

    They came out pretty neat and worked great so I thought I'd post some pictures.

    20170227_150629_resized.jpg 20170227_150345_resized.jpg

    Brake Line Mount4 exp.jpg Brake Line Mount4.jpg The brake line fits into the horizontal grove on the big piece, rotates 90 deg's and snaps/locks on to the brake line. Then the little piece snaps/locks over the brake line in the grove. (the CAD work was a lot of fun (if you enjoy CAD work))

    20170227_150520_resized.jpg 20170227_150559_resized.jpg They're pretty small so printing 6 sets of them (three per leg) on high quality only took a few hours.

    ---------

    20170227_150907_resized.jpg I tried a few simple and elegant, one piece versions but decided the two piece version was better.


    There's never a dull moment when you have a new tool... :gig:
     
    bmcj, Joe Fisher, Vision_2012 and 3 others like this.
  2. Feb 28, 2017 #2

    Victor Bravo

    Victor Bravo

    Victor Bravo

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    So.... there's no hinge for the smaller piece, which is now a separate loose part, and no over-center lock on it, and worse yet there is no hole in the locking tabs to put a retaining pin through to lock it.

    It requires a third piece to provide man-rated safety, which has to be sourced from a third party vendor, and further subjected to an entirely new quality control and inspection process.

    Even more egregiously, this third piece (a plastic wire tie) is not reusable, which places the entire assembly into non-compliance with virtually all of the "green" and environmental responsibility initiatives throughout the nation.

    Well, I just figured an over-thought standoff is deserving of an entirely over-wrought analysis !

    ;) ;) ;) [​IMG] [​IMG] [​IMG] [​IMG] [​IMG]

    (I'll take a dozen of them !)
     
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  3. Feb 28, 2017 #3

    Aerowerx

    Aerowerx

    Aerowerx

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    Hmmm. I see that you are in California. LA, none the less. I guess that explains it, then.;)
     
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  4. Feb 28, 2017 #4

    lr27

    lr27

    lr27

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    Nice. What's the life of a zip tie? I guess they're so easy to replace that if you know the expected life you could just put on new ones once in a while?
     
  5. Feb 28, 2017 #5

    FritzW

    FritzW

    FritzW

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    Your right, no need to make a part with only two pieces when a part with 4 pieces would work almost as well. :gig:

    Kidding aside, as much as it goes against my "fewer and simpler parts" philosophy, once the parts are drawn the only difference between "good enough", "better" and "best" is an hour of print time. And since I just hit the print button and go to bed it doesn't matter if the print finishes at 3AM or 4AM, they're not going to get looked at until 8:30'ish anyway ;).
     
  6. Feb 28, 2017 #6

    FritzW

    FritzW

    FritzW

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    I think the life expectancy of a Nylon zip tie is somewhere between 5 minutes and 50 years :gig:. They make Stainless Steel zip ties but, in this case, I don't think they're worth the hassle. Once the gear leg fairings are on, the mounts are pretty much redundant, and since they snap onto the brake line "7 ways from Sunday" they can't fall off and FOD the runway.

    If I wasn't a chronic over-thinker and this wasn't a team build with a bunch of retired WSMR missile engineers I would have just used wrapped them with a little friction tape and been done with it. ...the life expectancy of friction tape is 1,236,439 years :gig:
     
  7. Feb 28, 2017 #7

    pwood66889

    pwood66889

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    Copyright them RIGHT NOW!! Else A/C $pruce or others will!!!
    Percy in SE Bama
     
  8. Feb 28, 2017 #8

    Victor Bravo

    Victor Bravo

    Victor Bravo

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    BTW Fritz, those are really neat little doo-dads, and it reminds me of something. I'm guessing you're a model airplane builder from way back, so this may be something you have noticed as well.

    There were a few model airplane companies that had a really significant line of small accessories. Goldberg, Du-Bro, Fourmost, Rocket City, Williams Bros., one or two others. They made all sorts of plastic parts, hinges, bellcranks, clevises, control horns.

    Perhaps using the imaginaiton, technology and equipment you have (that brought us really clever brake line standoffs), you can create the same general principle as an innovator and supplier of innovative and time-saving doo-dads for homebuilt airplanes.

    For example, on my Taylorcraft, I was always thinking about small bubble and blister fairings to go over the ends and attachments of the tail brace wires. They would be useful for a small drag reduction, and a big shield against water, dirt, etc. I always thought about small vacuformed model airplane canopies, but the truth is a small printed or molded part designed for it would be really neat.

    Point is, there may be an interesting niche that a clever guy like you can fill. Probably not "big money", but enough to pay for your toys and write off your fuel.

    - Small teardrop blister fairings for exposed nuts and bolts, such as all the fasteners holding jury struts together, or flying wires, or little intersections where pitot and static lines are exposed.

    -Small parts similar to your standoffs that snap together to attach instrument tubing to the backs of instruments, but allow the tube to be removable instead of stuck on those horrible barbed fittings.

    -Dis-assemble-able tube fittings that allow easy connections between instrument lines to be adjusted, moved, add/delete instruments more easily.

    -Standoffs that allow wires or Bowden cables to be attractively clamped to a control stick

    -Small extenders for knobs, switches, altimeter knobs, etc. to be more easily reached by the pilot. A lot of switches and knobs are really inconvenient to reach without un-doing your shoulder harnesses.

    -Glare shield "eyebrows" or shades that minimize light reflections on instrument faces.

    -Glare shields for small GPS and tablet screens to make the easier to see, minimize reflections

    "Better mousetrap" machined or printed grommets that allow a firewall pass-through for small wires, sensors, etc.

    -A better Adel Clamp that somehow has a catch or tab that keeps it closed while you insert the srew or bolt.

    Anyway.... your clever idea got my wheels spinning, and I thought I'd plant the idea in your head.
     
  9. Feb 28, 2017 #9

    gtae07

    gtae07

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    Some of these already exist!

    -Small parts similar to your standoffs that snap together to attach instrument tubing to the backs of instruments, but allow the tube to be removable instead of stuck on those horrible barbed fittings.
    -Dis-assemble-able tube fittings that allow easy connections between instrument lines to be adjusted, moved, add/delete instruments more easily.
    https://www.mcmaster.com/#push-to-connect-tube-fittings/=16js4d8

    -A better Adel Clamp that somehow has a catch or tab that keeps it closed while you insert the screw or bolt.
    This one's called an Adelok, but good luck actually finding one. I've seen and held one in person.
    A company called Umpco also makes one, with a "tang lock" or "lock foot".


    -"Better mousetrap" machined or printed grommets that allow a firewall pass-through for small wires, sensors, etc.
    http://www.aircraftspruce.com/catalog/elpages/firewall_penetration_kit.php?clickkey=8172
    Something like this is your best bet for a safe passthrough that won't be burning through in short order. It's not as clean as some of the other solutions but it's going to work better in a situation where you actually need the "fire" part of firewall.
     
  10. Feb 28, 2017 #10

    FritzW

    FritzW

    FritzW

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    I was thinking something more like starting a "homebuillt airplane parts" category on Thingiverse. Whenever someone comes up with a part for a homebuilt they post it to thingiverse, anyone who wants the part can download it.

    If you don't have a printer just click the "have it made for you" button, someone will print it for you -cheap- and send it to you. Lots of folks on thingiverse don't have CAD software or a printer, they just go there to have things made.

    I'd rather see some high school kid who's a 3D printer geek make a few bucks than AS&S and a factory in China.
     
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