WHY are there so many sizes of launch lugs??

Discussion in 'Ground Support' started by prfesser, Nov 11, 2019.

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  1. Nov 11, 2019 #1

    prfesser

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    1/8, 3/16, 1/4, 3/8, 1/2 etc.

    Granted, no one uses (should use) 3/8 or 1/2" rods anymore...but why in the dickens did the manufacturers (Yes, I'm looking at YOU, Estes! And a few others...) decide that so many different sizes were needed in the first place?

    IMHO two sizes should be enough. 1/8" for small models, 1/4" for larger ones that need something bigger, railbuttons for everything else.

    I'm genuinely interested in the "why". And while we're at it, maybe the manufacturers of mid- and high-power kits could include a pair of railbuttons instead of a launch lug. No need to open the kit bag, just staple a tiny bag containing railbuttons to the cardboard hangy-thingy at the top.

    Best -- Terry
     
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  2. Nov 11, 2019 #2

    neil_w

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    *raises hand*

    I think it's simply the desire to avoid absurdly oversized lugs on smaller rockets. Lugs are not the most beautiful part of a rocket; the smaller and less obtrusive the better. Of course there's nothing stopping you from putting oversized lugs on your rockets if you want to have more flexibility at the pad.

    Also remember history... Lugs were 1/8" at the beginning, and then when motors and rockets started to get bigger they added 3/16", which was enough for those rockets (and still is). And then they added 1/4" later on, etc. It's not like when Estes started up they rolled out 10 different lug sizes right from the get-go.

    Personally I don't have any problem managing the different-sized lugs. 18mm rockets get 1/8", 24mm rockets get 3/16", and larger gets 1/4" or buttons.
     
  3. Nov 11, 2019 #3

    DaveW6DPS

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    It took a while for anything to be standardized in high power rocketry.

    There were numerous companies building kits of various sizes and they simply used what was available and was (hopefully) strong enough.

    For some time we have been transitioning to using equipment rack parts, because there are strength advantages.
     
  4. Nov 11, 2019 #4

    dr wogz

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    And I doubt Estes (or ...) want to start including a mini rail in their starter set. That would immediately require a re-design of their port-a-pad!

    Adding buttons makes sense, but adds complexity to the build.
     
  5. Nov 11, 2019 #5

    heada

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    1/8" and 3/16" were standard Estes. 1/4" was added for NCR based kits. 3/8" was never really popular in my eyes. 1/2" was the standard for HPR until rails and buttons.
     
  6. Nov 11, 2019 #6

    thequick

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    I’d be curious to hear more about the introduction of rail buttons. I picture some random guy showing up to a launch with a piece of 8020 and saying “watch this!”. (Right after “hold my beer”). Yet somehow we’ve standardized on buttons for hpr
     
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  7. Nov 11, 2019 #7

    DaveW6DPS

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    The first "rail buttons" I remember seeing were actually washers sized for Unistrut on a big (150 pound) rocket.

    Estes will not likely use mini- or micro-rail buttons, but they are available and our club has a few rails for the front row.
     
  8. Nov 11, 2019 #8

    Bat-mite

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    To sell different sized rods ... ?
     
  9. Nov 11, 2019 #9

    dhbarr

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    In order to keep up with the insanity of MMT sizes, of course :-D
     
  10. Nov 11, 2019 #10

    new2hpr

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    Estes used to have a launch rail along with rods in their launch parts section (early '70s maybe?))
     
  11. Nov 12, 2019 #11

    prfesser

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    Granted that larger and larger lugs may have arisen with increased impulse...but there is no longer a need for all these sizes, and lugs included with the kits ought to reflect that.
     
  12. Nov 12, 2019 #12

    heada

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    Besides PML, who provides lugs bigger than 1/4" with kits?
     
  13. Nov 12, 2019 #13

    K'Tesh

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    However, Estes did sell rails and the Omega included instructions on how to make the rocket accept rails.
     
  14. Nov 12, 2019 #14

    cwbullet

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    Because there are larger rockets and motors. Rail buttons are relatively new.
     
  15. Nov 12, 2019 #15

    K'Tesh

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    Other than the Omega... I'm unaware of any other kit that had parts and plans that would allow the builder to make their rockets rail compatible. Does anyone know of other kits that featured this as well?
     
  16. Nov 12, 2019 #16

    dhbarr

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    I thought it was always just considered an advanced technique?

    "
    Launch Rail (“C” rail):
    Metal rail with a hollow square shape; its cross section form-
    ing a squared C; used to guide a model during its first few feet of
    flight until stabilizing velocity is reached.
    "


    Screenshot_20191112-045707.jpg
     
  17. Nov 12, 2019 #17

    cwbullet

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    Which Omega kit?
     
  18. Nov 12, 2019 #18

    K'Tesh

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    All of them...

    K-52
    K-52P
    1200

    Estes Omega K-52 Instructions (Rail Guide Detail).png


    [​IMG]
     
    Last edited: Nov 12, 2019
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  19. Nov 15, 2019 #19

    Initiator001

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    The originator of model rocketry as we know it, Orville Carlisle, used a 1/4" diameter WOODEN dowel as the launch guide for his first models (the Mark I & Mark II).

    When Model Missiles Inc. (MMI) released the first mass-produced model rocket kit and starter set in 1958, they had changed to a 1/8" diameter steel launch rod. Originally it was a single piece rod 36" long but the USPS liked to bend/fold/twist the long boxes so the second production run of starter sets featured a two-piece 1/8" diameter launch rod, each piece 18" long to fit in a shorter box.

    The Mini-Maxx motor powered kits released by Centuri Engineering in the early 1960s featured 3/16" launch lugs. Interestingly, when the Enerjet catalog came out in 1972, the Enerjet kits had 1/8" diameter launch lugs.

    When I bought my first mid-power kits in 1985 from the original NCR and LOC/Precision, the launch lugs worked with a 1/4" launch rod.

    The LOC/Precision Magnum kit I bought in 1987 had 1/2" launch lugs.
     
  20. Nov 15, 2019 #20

    PhlAsh

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    because a uni-struct rail button looks silly on a Mosquito.
     
  21. Nov 24, 2019 #21

    dpower

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    The Sirius Saturn V is designed to launch from a 1/2" x 4' rod, and includes an internal aluminum lug. I've been too chicken to launch it that way, though, and use a 6' rail.
     
  22. Nov 24, 2019 #22

    BEC

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    That C rail could be used with a regular 1/8 inch launch lug atop a 1/16 inch dowel as a standoff (see the Astron Constellation for an example). I wish that was still around. I’ve had less than stellar luck with the 10mm micro rail that uses nylon 2-56 screw-based buttons. It binds too easily. But the lug on a standoff in the C-shaped rail should have worked very smoothly.

    [Oh - I see Jim (K’Tesh) has also posted about this arrangement and the Omega.]

    Of course the first launch lugs were for 3/8 inch dowels. See Rock-a-Chute Mark II, which used a spent motor casing for a launch lug, and those first Carlisle hand-loaded motors were half an inch OD.

    [I see Bob Sanford just posted above that it was 1/4 inch diameter dowels. One of us is right, and I’d bet on Bob.]

    I guess I should have read this thread more completely.....you can ignore me if you like...
     
  23. Nov 24, 2019 #23

    BEC

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    K-35 Astron Constellation.

    Awhile back I went trying to find something that was about the right size/cross section as the old Estes C-rail, since I have no idea what the material was used for originally. Since today’s most common rails are really industrial shelving framework materials, I doubted what Estes was selling was purpose-made for them.

    The closest thing I found at the time was curtain track for use in RVs. But I never followed through enough to actually get some.
     
    Last edited: Nov 24, 2019
  24. Nov 24, 2019 #24

    rharshberger

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    I wonder if a piece of aluminum square tube (same dimension across flats as the c-rail) with a 1/8" slot down one side would be similar.
     
  25. Nov 24, 2019 #25

    Lawndart

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    The first commercial rails and rail buttons I remember were from Blacksky.
     
  26. Nov 24, 2019 #26

    kuririn

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    WHY are there so many sizes of launch lugs??
    Same reason as why there are so many sizes of launch rails.
    Because there are so many sizes of model rockets.:D
     
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  27. Nov 24, 2019 #27

    kuririn

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    My older Minie Magg kit had a 1/2" lug and slotted fins with wooden "keepers" to lock the fins in. Newer kits ditched the keepers, don't know if they also ditched the 1/2" lugs.
    BTW about five years ago I ordered an 8' aluminum 1/2" rod from Graingers online and had it shipped to the local Graingers here for pickup.
    Free shipping! It must have cost them at least twice the cost of merchandise to ship from CONUS to Hawaii.
    Laters.
     
  28. Nov 25, 2019 #28

    Woody's Workshop

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    I use to use a straw from the kitchen drawer. And straighten out a wire coat hanger from the closet and stuck it in the ground.
    That was back when a Big Bertha was $1.75....
    I can't afford rails, buttons or large rockets.
    But I do have regular 1/8", 3/16" & 1/4" launch lugs from 5/8" to 12" long, and rods 36" & 6' long these days.
    As far as the Estes Lightning Bold Porta Pad, they are about as flimsy a thing you can use. IMHO, they are junk.
    I have several older pads I use in Black, Yellow, Red and Orange that are much more sturdy.
    And the early Orange one I have stands taller than the rest and much more webbing like it should have.
     
  29. Nov 25, 2019 #29

    MikeyDSlagle

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    The Mega Magg I bought last Christmas had either 3/8" or 1 /2" lugs with it.
     
  30. Nov 25, 2019 #30

    JoeG

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    According to my recollection: As High Power rocketry advanced to larger rockets and motors accessories got bigger but not necessarily better. Before clubs started moving to rails there were rods. As rockets got bigger, lugs and rods got bigger. 1/2" rods have been mentioned but does anyone remember the 3/4" and even 1" lugs and rods on some of the M powered fights? These were big, heavy rockets to keep them in sight. Besides, electronics (for rockets) were in their infancy. Eventually someone realized there should be a better way and many, if not most, clubs worked their way to the rail systems.

    I still have a rocket with 1" lugs on it.
     

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