1:53 scale Saturn V

Discussion in 'Scratch Built' started by grandcross, Mar 14, 2019.

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  1. Apr 12, 2019 #31

    grandcross

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    I certainly know the frustrations of debugging 3D printer issues. My only advice is to keep tinkering with it after you get the new one. I had to play with mine off and on over 2 years to start getting acceptable prints again, but the knowledge I've gained is indispensable. I didn't have the option of an upgrade at the time. Now I'm thinking of building my own... after this project :)

    And then you'll have 2 printers!
     
  2. Apr 12, 2019 #32

    grandcross

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    Files uploaded to Thingiverse. This includes both 1:53 scale parts and 1:52 (actually 1:51.63 as noted earlier). This includes the top of the S-IVB but not the bottom. That's still in progress.

    https://www.thingiverse.com/thing:3513106
     
  3. Apr 12, 2019 #33

    grandcross

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    Oh, and I've added to the video series on YouTube!
     
  4. Apr 29, 2019 #34

    Thorfire

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    Could you check the mating diameters of the 52 SIVB upper and the 52 SLA Deployable? They seemed extremely tight when I printed them (I should be able to get these to fit with a bit of sanding). Looking at SLA files, there seems to be a diameter mismatch.

    upload_2019-4-28_20-15-24.png

    upload_2019-4-28_20-11-37.png
     

    Attached Files:

  5. Apr 29, 2019 #35

    grandcross

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    Thanks for the heads up! It's late tonight, but I'll look into it first thing tomorrow
     
  6. Apr 29, 2019 #36

    Ez2cDave

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    S5Dwg_05.jpg
     
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  7. Apr 29, 2019 #37

    grandcross

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    So as I'm sure you already suspected, the SLA models are incorrect. The 52 and 53 versions are cross labelled. I'll correct those shortly on thingiverse, but you can also go ahead and print the other one if you don't want to wait. I'll double check the other models as well.

    In the meantime, work is progressing on the bottom of the SIVB, and I should be uploading a video on the Rocksim model for the flight version today or tomorrow. I'll DM you the information to access the sim file.
     
  8. Apr 29, 2019 #38

    grandcross

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  9. Apr 29, 2019 #39

    Thorfire

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    The SLA or the SIVB models? The SIVB is small relative to the SLA..
     
  10. Apr 29, 2019 #40

    grandcross

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    These are the correct scaled dimensions for the positions you've indicated

    SLA
    1:52 2.348
    1:53 2.411

    S-IVB
    1:52 2.357
    1:53 2.419

    It looks like you've accidentally (due to mislabelling) printed the incorrect SLA for 1:52.
     
  11. Apr 29, 2019 #41

    Thorfire

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    Wouldn't the 1:52 be the larger parts?
     
  12. Apr 29, 2019 #42

    grandcross

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    Oh FFS. I need more coffee. Yes, the numbers are right but inverted. The correct numbers are:


    SLA
    1:53 2.348
    1:52 2.411

    S-IVB
    1:53 2.357
    1:52 2.419

    It doesn't help that I'm working from 1:48 drawings, designing to 1:22, and then converting to 1:52 and 1:53. If I seem confused it's only because I am!

    So I guess it's my S-IVB that's mislabeled.
     
  13. Apr 29, 2019 #43

    grandcross

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    And that boys and girls is the story of how the mars lander crashed because someone converted the units wrong!
     
  14. Apr 29, 2019 #44

    Thorfire

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    Young guns who didn't learn standards... Ignoring ASME Y14.5 section 1.6 is a good one for mixing up inch and SI units....
     
  15. Apr 29, 2019 #45

    mikec

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    I worked on that program. 1, it was an orbiter, not a lander, and 2, it was a lot more complicated than just a units conversion, although that was the initial root cause (confusion between newtons and pounds-force, actually.)
     
  16. Apr 29, 2019 #46

    Thorfire

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    Thanks for enlightening us. It's all too easy to point fingers and laugh in total ignorance. The original headlines were a good example of that.
     
  17. Apr 29, 2019 #47

    grandcross

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    Yes, that was not an attempt to mock or denigrate. Just pointing out how it's easy to get confused over small but critical details.
     
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  18. Jun 2, 2019 #48

    grandcross

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    It's been a while since I've posted an updated, but that doesn't men I haven't been busy! The stack is growing slowly but surely.

    IMG_1309.JPG

    The last two pieces of the SII stage are ready for printing with the printer humming away as I type this. The stage is printed in 4 parts. The first 2 are shown in the image above, and part 3 is on the printer. My printer isn't the best so I have to print at a slow 40 mm/s meaning these parts are taking about 35 hours to print.

    IMG_1311.JPG

    The print shown here had an error (the LH2 fill and drain feature in the center of the print) wasn't rotated to its correct position. It was off by a small but noticeable 5.8 degrees. Of course I discovered that 17 hours into the print.

    There's a lot of detail that went into this stage. One of the reasons it's taken me so long to post an update was I was having some difficulties with some of the model components, but the FreeCAD user forum has been quite helpful. After a week of frustrated hair pulling, a couple of minutes on the forum solved my problems. There's a lot of details in here!

    Screen Shot 2019-06-01 at 9.35.40 PM.png

    The files are available now on my Patreon account, and as is the policy will be available on Thingiverse in 4 weeks.

    I've been meaning to get a new video up for a while now, and now seems to be a good time to pause for that. The SiC stage will have a few challenges of its own.
     
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  19. Jun 2, 2019 #49

    OverTheTop

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    Nice modelling there :cool:.
     
  20. Jun 2, 2019 #50

    grandcross

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    Thanks! Each detail on its own isn't too bad, but man there are a lot of them :D
     

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