IJN Tone (formerly Something Silly)

Discussion in 'Digital Design and Fabrication' started by GregMcFadden, Nov 19, 2023.

  1. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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  2. Kotori87

    Kotori87 Well-Known Member

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    If you have a solid hull in Fusion360, you can set the material properties so it has the same weight of water, and you can find the displacement. Then you start slicing off the top of the hull until it matches your desired weight, and now you know your waterline. Or if you're like me, you can just print your model and start stacking ballast until it floats right, then update the model accordingly...
     
  3. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    What Kotori says... that is also what I do... I set the density to 1kg/m^3 and then slice it at the waterline... check the weight, which verifies that the hull is close enough.... then change the slice till I match the target weight.... and there is the waterline. Generally it will predict it a skosh higher due to the balsa sheeting, but it will be close enough
     
  4. Beaver

    Beaver 2020 Rookie of the Year Admiral (Supporter)

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  5. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    Just be careful in areas of strong curvature, as your approach will only be absolutely correct for regions of the surface where the surface normal is perpendicular to the axis of rotation for the 45 degree transformed plane . the answer you get will be close (generally) except at the bow and stern for most ships...

    for reference, the same image as before with red = 45 or more, using your approach. No substantial differences in areas that matter, but if you had a stumpy one (like a monitor) it would lie more.

    upload_2023-11-30_17-15-3.png
     
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  6. Beaver

    Beaver 2020 Rookie of the Year Admiral (Supporter)

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    What is your approach to alleviate this? Setting the plane at 45° was the only way I could get draft analysis to show me anything close to what I wanted. Lol
     
  7. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    there isn't one. That limitation has been in autodesk products for ages, and it exists only because some programmer somewhere said" hey no one drafts more than 15 degrees anyways, set the limit here"

    Practically, since the bow and stern are solid, you will be within the tolerance of model boats except on hulls which bulge out a lot like the monitors. in that case, do a 45 degree plane around the plane formed by the surface normals. Can't really describe it without a diagram. How I used to do this long ago check was to take an intersection curve at the angle that I am most interested in, and check there with a tangent line set 45 off the horizontal and tangent to the surface.
     
  8. Anvil_x

    Anvil_x Well-Known Member

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    Wow. yeah defs gonna use this when I run new hulls.
     
  9. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    and preliminary rib layout is complete. Time to lay out internals... then carve away excess mass of plastic/add mount points and water chaneling.

    upload_2023-11-30_23-13-55.png
     
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  10. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    progress on B turret.

    upload_2023-12-16_16-53-0.png
     
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  11. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    upload_2023-12-30_11-19-36.png

    PXL_20231230_190956133.jpg

    I am trying something different. The propulsion/rudder components are their own module... whether it is removable or permanently installed after assembly is TBD, but since I have to split the hull up for printing anyways, it doesn't really matter if I split it up in a manner that lets met get the propulsion and steering components fully assembled and tested while the rest of the hull design and print work progresses. First print showed some design errors / tolerance issues, second had a warping issue when I tried to print all three parts at the same time... Second print is probably usable but I will try for a third...
     
  12. JustinScott

    JustinScott Well-Known Member

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    I like the locking mech you got there….
     
  13. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    The print is starting stern to bow now. That will let me get the mechanicals done and then work on some of the design work while the stern is printing. Unfortunately I ran out of all of my bright colors bought for my girls so back to grey
     

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  14. Boatmeister

    Boatmeister Active Member

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    Interesting methodology of printing the hull. :cool:
     
  15. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    It is an experiment and frankly not a bad hull to do the experiment with. We will see how it turns out.
     
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  16. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    Slowly it grows
     

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  17. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    3.5 lbs at this stage
     

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  18. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    Well the gearbox works... May make a few tweaks to it for ease of access
     

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  19. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    and an update. Shielding is in, cannon is designed and built, ready for test firing. This is the 4th of them.... Third fired fine but was a pain to print .... Propulsion module worked out well enough. Need to make some drag disks and mount dummy shafts.
     

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  20. Anvil_x

    Anvil_x Well-Known Member

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    Hey Greg, are you going to just bolt in the propulsion module with a silicone gasket around the edges for floating trials?