K'Tesh's OpenRocket Nosecone Library

Discussion in 'Rocketry Electronics and Software' started by K'Tesh, Jan 1, 2014.

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  1. Jan 1, 2014 #1

    K'Tesh

    K'Tesh

    K'Tesh

    OpenRocket Chuck Norris

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    [EDIT] I've renamed this thread to the "K'Tesh's OpenRocket Nosecone Library", as this is a more accurate description of what is found here. [/EDIT]


    [EDIT] I have created a tutorial on how to do this... The following was the inspiration and a collection of the results.[/EDIT]



    One of my friends is a Hollywood Prop Master (you've seen his work I'm sure... He made Arnold's costume (Mr. Freeze) in the Batman Franchise, and the Sword of Kahless (DS9), as well as the armor for Witchblade, and a lot of other work).

    One of his catch phrases (besides "I'm so fired!") is "Fake it until you Make It".

    It's truly amazing what real world cr*p goes into making the props you see on TV and in the Movies. From 10 feet if it passes for a gun, then it is a gun due to the limitations of TV's capability of clearly display images (before HDTV came about). I've seen actual props from Star Trek: TNG, and it was depressing how bad some of the hero props looked in close proximity.

    So, what has this have to do with OpenRocket?

    Well... Today I was trying to recreate the Estes Cineroc CM-8 camera, and I finally figured out how to do it in OR. First I created a nose cone that was 1/4" in length and 3/4" in diameter, Ellipsoid in shape. Next I created a transition that was the right length and shape (conical), finally adding the 1/8" flat area that precedes the Camera's housing. This is what it lead to:

    [​IMG]

    [EDIT] 2/1/2015 The image above, and the .ork file were based on Mike Jerauld's dimensional drawing, and not actual measurements of real Cineroc cameras. In my quest to make the ultimate reproduction of the Cineroc, I found errors in the drawing, so I've measured a Cineroc (and remains of a second one) to create the following (Hyperaccurate) rendering:

    [​IMG]

    [/EDIT]

    So, I started working on another pair of OR projects (a modified Citation Patriot, and Der Big Red Max). These call for the Estes PNC-60AH. Hmmm, the preloaded shape for the NC doesn't look like what I think it should.

    [​IMG]
    Estes PNC-60AH open rocket default

    I got lucky once, why not twice? I made my Ellipsoid NC 1/4" long, 1/2" in diameter, then combined that with my Ogive transition that was 6 5/8" long. I decided to try adding the NC's trailing cone as well (you have to remove this detail for the rocket simulations) by adding a phantom body tube that was the same size as the shoulder, then adding another conical transition. From that work, I get my variation of the PNC-60AH (Der Red Max, Citation Patriot), : [EDIT] UPDATED the file for more accuracy... Image is WYSIWYG

    [​IMG]

    Now that I have the concept on how to create these, I've created a version of the PNC-60RL (Sentinel, Magnum): [EDIT] Updated for more accuracy.

    [​IMG]

    And the Estes Pt. No. 072665 (QCC Explorer, Solar Warrior (#3225)):

    [​IMG]

    [EDIT] Here is a theoretical Estes PNC-60BB based on the real PNC-55BB (Black Brant II)

    [​IMG]

    [/EDIT]

    Now if I could only print, CNC, or Lathe my own parts...

    All The Best!
    Jim
     

    Attached Files:

    Last edited: Feb 20, 2019
  2. Jan 1, 2014 #2

    mrwalsh85

    mrwalsh85

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    FYI, not to poke fun or anything, but it's "...or turn my own parts."

    A lathe is used to turn parts. Hence the process known as "turning".

    Happy new year, everyone!
     
  3. Jan 1, 2014 #3

    K'Tesh

    K'Tesh

    K'Tesh

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    No offense taken, but I was right.

    Lathe: Verb
    lathe (third-person singular simple present lathes, present participle lathing, simple past and past participle lathed)
    To shape with a lathe.
    (computer graphics) To produce a 3D model by rotating a set of points around a fixed axis.​

    Did I mention that I'm an English teacher-in-training? I know that my capitalization was off, but does it really matter? Due to my age, training, frequent moves (lived in 5 states before I was 8, 9 states by the time I graduated high school (military brat)), and time outside of the Mainland US (Hawaii (ages 2-6), England (19-21)) I may use a more diverse dialect of English (e.g. O'ahu (<- the island I learned how to speak on), Kaʻaʻawa Valley (<-Near my childhood home), Hauula (<- My childhood home), cuz, haole, kane, humuhumunukunukuapua'a (YES! I can pronounce these like a native Hawaiian), colour, petrol, etc...) than other Americans.

    新年快樂! (<- YES! I can read and pronounce like a native Mandarin speaker, too...)
    陳吉 (也被稱為 Jim)
     
    Last edited: Jan 1, 2014
  4. Jan 1, 2014 #4

    CarVac

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    I take issue with whatever dictionary you cited, English teacher or not. No wood turner would call it "lathing" and so I wouldn't either.
     
  5. Jan 1, 2014 #5

    bobkrech

    bobkrech

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    Regardless of a new usage for an old word, the Estes Cineroc CM-8 camera can not be turned on a lathe as it is not axisymmetric. Could be painfully done on a 3-axis CNC or easily done on a 4-axis CNC.

    Bob
     
  6. Jan 1, 2014 #6

    Mojo_wire

    Mojo_wire

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    "That word .... I do not think it means what you think it means"

    He distinctly said "to BLATHE", and we all know to blathe is to bluff .... So he probably wasn't making nose cones at all but was playing cards! And he cheated!
     
  7. Jan 1, 2014 #7

    VonMises

    VonMises

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    Nice work manipulating O.R. to your evil intent.:)

    I read somewhere that Malcolm Reynolds pistol in the Smithsonian.

    Regarding your terms:
    Technically you may be correct. However, if you walk into a machine shop and ask them to “lathe” something for you, don’t be surprised if they chuckle.

    I’ve turned thousands of parts for various projects, but I’ve never lathed anything.

    BTW, we homeschool.
     
    Last edited: Jan 1, 2014
  8. Jan 1, 2014 #8

    TheTellurian

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    I take issue with the assumption all lathists are semi literate, don't know how to use a lexicon and that any word can have different meanings and ways of use. I just invented a word [lathist] which is permitted under the rules of the language. Just ask Shakespere.:lol:

    K'Tesh; Can you post the OR file, I don't understand exactly how that was done? I design and build unusual rockets and employ design workarounds to do so. Any trick is useful.:D


    Richard
     
  9. Jan 1, 2014 #9

    K'Tesh

    K'Tesh

    K'Tesh

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    I don't know if you'd call him a wood turner, but Hollywood Prop Maker, and Mythbuster, Adam Savage frequently uses the term as a verb in several online videos. (e.g. this one...(right around the 1:49 minute mark and the 5 minute mark) :p :neener:



    I'm amazed at how many prescriptivists are here... Truth of the matter is, more people are speaking (and learning to speak) English in China than in all of the inner circle of English speaking countries (England, Ireland, U.S.A., Canada, S. Africa, Australia, New Zealand) combined. There is no such thing as a standard English, and the language is more foreign now than it ever was...

    [​IMG]

    You can take up my use of "lathe" with Daniel Webster if you like, but it won't change the fact that it's been used as a verb since 1903 CE.
     
    Last edited: Jan 26, 2017
  10. Jan 1, 2014 #10

    K'Tesh

    K'Tesh

    K'Tesh

    OpenRocket Chuck Norris

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    Hi Richard,

    Shakespeare... credited for ~1.7K words added to the English language. Nice Job citing him... I was going to hold that card for another round if needed. Oh well.

    I sent you an email. I haven't had any luck posting .rkt files here. I don't know if there is a way. I'll look again.

    [EDIT]Say, what do you know... I was able to do it! :D [/EDIT]

    Let me try to explain how I did it. First, the hemispherical portion is an ellipsoid a fraction of an inch long, and a fraction of an inch wide, then I add a transition (conical, ogive, whatever), the transition gets the shoulder. The tail cones on these images is for show only, and cannot be replicated in the simulations of an actual rocket.
     

    Attached Files:

    Last edited: Feb 20, 2019
  11. Jan 1, 2014 #11

    TheTellurian

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    Thanks I'll look at it later, need to look after the 90 year old mother right now.


    Richard
     
  12. Jan 1, 2014 #12

    VonMises

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    This is probably due to the fact that people in England, Ireland, U.S.A., Canada, S. Africa, Australia, New Zealand already speak English. Therefore they don’t need to learn how. So it makes perfect sense that more people in China are “Learning” to speak English.

    Have you tried reading an instruction manual from Tenergy? I certainly hope the Chineese learn to speak English. Because they certainly don’t “Speaky Eng-a-rish many happy” presently.

    You’re only partially correct. And , NO, I will not take up your use of the term. I’ll side with Merriam-Webster because this way, I won’t be laughed at in the shop. According to Merriam-Webster:
    Turn: transitive verb.
    7 a : to shape especially in a rounded form by applying a cutting tool while revolving in a lathe

    In addition, it appears your cartoon makes the counter point to your position.
     
    Last edited: Jan 1, 2014
  13. Jan 1, 2014 #13

    K'Tesh

    K'Tesh

    K'Tesh

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    I'm not asking anyone who turns (or lathes) materials to take up my use of the term, just accept that it is (and was) a proper use of the word.

    One statistic I'll pass on... There are more students learning English in China (Mainland) than there are PEOPLE in the US. (whether they are learning English, or using English, or not).

    I always thought that TRF was a place for us to share knowledge, for some to teach, and others to learn (or not). Crazy thought that? Eh?
     
    Last edited: Jan 1, 2014
  14. Jan 1, 2014 #14

    VonMises

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    Perhaps I didn’t explain myself very well. We are in agreement on this. All I’m trying to do is point out that when you say:
    “Now if I could only print, CNC, or Lathe my own parts...”
    You’ll get funny looks and perhaps a few chuckles from the folks that turn parts.

    OK, and people in the English speaking countries don’t need to learn English, a distinction without a difference. On the other hand, I suspect that IF the Chinese decided to take up English as their primary language, it would have a global influence.

    It is. You learned that we don’t “lathe” parts, we turn them.:)
     
  15. Jan 1, 2014 #15

    TheTellurian

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    :facepalm:

    K'Tesh: I've looked at the file and now see what I didn't understand, in the first image the camera pod, sticking out the side, is shown. How did you do that? My avatar is one of the rockets I've built using similar techniques.


    Richard
     
  16. Jan 1, 2014 #16

    K'Tesh

    K'Tesh

    K'Tesh

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    The Camera's fairing is actually a fin (that's why I used the term "fake it"). If you were to "dissect" the design, you'd see it's nothing more than an airfoil shaped single fin of the correct(ish) shape (the actual fairing is offset from the centerline of the camera housing by 1/4" and slanted (so, one side is actually taller than the other)) and size.

    To get the shape right, I found an image of the fairing online, then I had to crop the fairing out of the image. I then had to convert it to a black and white image.

    When it came time to add the "fin", I selected "Freeform" then in the "shape" tab, I selected "Import from Image". Next, I found the appropriate image, selected it. This was oversized by several inches. So, I then had to use the "scale" feature to get it to the correct size.
     
  17. Jan 1, 2014 #17

    K'Tesh

    K'Tesh

    K'Tesh

    OpenRocket Chuck Norris

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    Last edited: May 21, 2014
  18. Jan 1, 2014 #18

    VonMises

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    Indeed. Especially those who screw the pooch then try to defend it, rather than just saying "Oh, thanks, I didn't know that." But hey, it kinda goes with the thread title "Fake it until you Make it".

    Really, thanks for the tip. It works great, and it solved the problem I had with the A20 Demon NC. It made percect sense. As soon as you mentioned a short Ellipsoid the light came on.
     
    Last edited: Jan 2, 2014
  19. Jan 1, 2014 #19

    daveyfire

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    thank u, next
    It's definitely one of the highlights on Christmas morning!
     
  20. Jan 1, 2014 #20

    K'Tesh

    K'Tesh

    K'Tesh

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    If you can't dazzle them with Brilliance... baffle them with Bulls**+.

    Now, I'd like to see what you came up for with the A20 Demon NC. Can you post the file?
     
  21. Jan 1, 2014 #21

    VonMises

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    We finally just went to youtube.
     
  22. Jan 1, 2014 #22

    VonMises

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    Lolz, you ok GI.

    Haven't made the A-20 yet. Just played around so far. But I'll have to in order to get an accurate sim. I'll be doing the same with my 3 inch Red Max. All I did was take the top inch off of a PML Ogive, but I wasn't able to put it into O.R. until now.

    I'll post one in a few. Gotta warm up the O.R. laptop.
     
  23. Jan 2, 2014 #23

    K'Tesh

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    This isn't perfect, but when I read about the A20 Demon NC, I was reminded of the Ramjet type of nosecones (PNC-55D). I don't have one to measure from, but I did find an image. I know that this is not accurate, but for the info I have, it shows what is possible with the method I've found for recreating designs.

    [​IMG]
     

    Attached Files:

    Last edited: Feb 20, 2019
  24. Jan 2, 2014 #24

    VonMises

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    Now you’re just showing off. Not complaining though.

    Here’s the A-20. It’s really nothing more than the front of your Cineroc, You can see in the upper left it’s just a short Ellipsoid, with a long conical transition, and a short section of airframe. The shoulder is a coupler and bulkhead.

    [​IMG]

    I just deleted the conical NC I had on the rocket and built it up backward from the top of the payload bay with a coupler for the shoulder. That’s why there’s a coupler and bulkhead in the upper section of the payload bay. On the Red Max, I’ll delete the old NC, then start with an ellipsoid NC and inserted the components between the NC and airframe

    Here it is in 3D. A .5 inch ellipsoid with a 1.125 inch base leaves a small bit of transition at the top of the conical section. Still it’s far more accurate than the conical NC it had:

    [​IMG]

    And here it is finished:

    [​IMG]
     
    Last edited: Jan 2, 2014
  25. Jan 2, 2014 #25

    CarVac

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    How's the difference in simulation? Are CP and drag relatively consistent between the two (only subsonic, obviously)?
     
  26. Jan 2, 2014 #26

    VonMises

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    Sorry, I didn’t record the CP or CG before altering the NC. However, this is a long rocket with stability over 6 to stat with. I’ll remember to keep track of this when I alter the Red Max.

    Here’s the sim data.

    Before:
    [​IMG]

    After:
    [​IMG]

    It appears to have lost a little velocity off the rod, but picked up some altitude, and time to altitude dropped a bit.

    Overall, the difference between the simulations is small, almost meaningless. But until now, I had no way of knowing this. Still, the model is more accurate in O.R. and this particular issue is the one that really bugged me.

    Thanks K’Tesh
     
    Last edited: Jan 2, 2014
  27. Jan 2, 2014 #27

    K'Tesh

    K'Tesh

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    OpenRocket Chuck Norris

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    Nice looking job you did on the nose cones there... (both real and sim)

    BTW. On the transitions, you can add a shoulder to them...

    [​IMG]


    Glad that my tips are helping out.

    All The Best!
    Jim
     
    Last edited: Jan 2, 2014
  28. Jan 2, 2014 #28

    scsager

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    Wow nice job - awesome work with OR. - Inspiring even!
     
  29. Jan 2, 2014 #29

    K'Tesh

    K'Tesh

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    And a new one to add to the list... The Estes PNC-60NA (Loadstar II, Warp II)

    [​IMG]

    .
    .

    [EDIT] Found out I had this as the PNC-60A, when it's actually the PNC-60NA. Sorry for any confusion.
     

    Attached Files:

    Last edited: Feb 20, 2019
  30. Jan 2, 2014 #30

    VonMises

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    OK, mentioning the transition, had me a bit confused for a second. Once I figured out that both ends can be the same dia, it all came together.

    So I was able to replace a 1.5 inch section of airframe, coupler and bulkhead, with a single transition.

    Very nice.

    The real one is balsa that I covered with a Kevlar sock, then coated with an impact resistant resin. Good thing too, as I inadvertently tested it with 5 ft drop onto concrete.
     

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