Bench Testing a Rocket....

Discussion in 'Low Power Rocketry (LPR)' started by lakeroadster, Jun 29, 2018.

  1. Jul 1, 2018 #21

    lakeroadster

    lakeroadster

    lakeroadster

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    With the D12 it will have 6.67 lbs of thrust :D

    Trust Buy Verify... having spent the last 30 years as a Quality Assurance Manager I tend to like to verify things.
     
  2. Jul 1, 2018 #22

    Zeus-cat

    Zeus-cat

    Zeus-cat

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    If you do a bench test and the rocket fails can you modify the design? If not, why not just fly it?
     
  3. Jul 1, 2018 #23

    Flyfalcons

    Flyfalcons

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    You didn't answer my question in earnest though. Do you have some reason to believe that the methods you have used to construct your rocket, which have been proven to be effective during millions of other LPR flights, will be inadequate and potentially fail?

    We've already agreed that your deployment system will work. And if you use a hose clamp to restrain the motor, then you will not be applying pressure to your centering rings. So what useful purpose is there to bench firing your rocket?
     
    Last edited: Jul 1, 2018
  4. Jul 1, 2018 #24

    lakeroadster

    lakeroadster

    lakeroadster

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    No reason at all.

    Useful purpose... Opinions vary. I'd like to try it simply because I never have bench tested a rocket. I personally think it will be interesting.

    Many people would say Model Rocketry has no useful purpose.. again, opinions vary.

    Do you understand the concept of "Trust but Verify"?

    The rocket is made from various components that are glued together. Any of the components, or the adhesive materials used to hold the components together, could fail.

    Lets assume the rocket is restrained by placing a compressible foam surface in front of the fins. Thus the fins would be subject to the forces resulting from the thrust of the engine.

    And also assume no hose clamp is used to restrain the engine, thus the rockets engine block would also be tested.

    Some people may find those tests useful.

    _____________________________________________________

    I messed around with some FEA today, looking at stresses on the rocket if it is constrained via the nose cone.. or restrained via the front of the X-wings.
     

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    Last edited: Jul 1, 2018
  5. Jul 6, 2018 #25

    milehigh

    milehigh

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    I agree with an earlier post about building a 'boilerplate' test model for such activities; one that just has the basic airframe and no time or money spent in applying a paint/detailing job. If the model survives the static test, it can then be flown (still nekid) in actual configuration. If it still survives, then it's maybe time for a good paint job, after which a second model should be built with all the full detailing. This is standard (or should be) procedure for building a scale model that may have marginal stability concerns, or some type of staging or cluster system that needs to be ironed out before any full-blown detailing is done.
     
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