1/8" Lugs on a 3/16" rod?

Discussion in 'Low Power Rocketry (LPR)' started by Tom, Jul 20, 2019.

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  1. Jul 20, 2019 #1

    Tom

    Tom

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    Any issues launching a rocket with 1/8" lugs off a 3/16" rod?

    I've done it before and did not witness any issues.

    I kind of have standardized on 1/8" lugs but forgot the bigger rod! :(
     
  2. Jul 20, 2019 #2

    Oldschool77

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    Did you mean 3/16 lugs on a 1/8 rod? If so, that's ok so long as it's not heavy enough to create rod whip. If as written, no. Won't fit.
     
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  3. Jul 21, 2019 #3

    rocketguy101

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    Jim Flis taught me a neat trick if you want to put larger lugs on a rocket (swap out 1/8" to larger 3/16")...rather than completely remove the lug, slice most of it off length-wise, then you have a nice pad to glue the new lug, cover it with a glue filet and nobody's the wiser
     

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  4. Jul 21, 2019 #4

    Tom

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    Ummm yea... the other way around... oops :p

    That's a great idea to mod the launch lug. Thank you very much!
     
  5. Jul 21, 2019 #5

    Steve Shannon

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    Launch rods tend to bend easily anyway. Building a rocket to use the next size larger rod is a good thing, but flying a rocket on a size smaller rod could result in chatter and excess rod whip. Many RSOs will not allow it, including me.
     
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  6. Jul 21, 2019 #6

    BABAR

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    I am a scratch builder, and I have found paper soda straws a great inexpensive alternative to stock style 1/8” and 3/16” lugs, although the diameter of the straw is oversized for both rods.

    I am not shooting for performance/altitude, so the extra drag doesn’t bother me.

    I use a 3/16” rod for larger rockets, a 1/8” for smaller ones.

    I haven’t had a bad experience yet that I could attribute to the oversized lug.

    Agree that a 1/8” lug is generally too tight on a 3/16” rod and will likely bind on launch
     
  7. Jul 21, 2019 #7

    DaveW6DPS

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    I am starting to use mini rail buttons more than 3/16" rod. They are stronger on rockets that would use 3/16" rods and our club is starting to have them at launches..
     
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  8. Jul 24, 2019 #8

    Flyfalcons

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    There are some rockets that come with 3/16 lugs, that are light enough to comfortably use a 1/8 rod. It's a "use your best conservative judgment" scenario.
     

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