Is rhino still the way to go for a hobbyist?

Discussion in 'Software' started by pironiero, Nov 30, 2025.

  1. SukiSolo1
    Joined: Dec 2025
    Posts: 2
    Likes: 3, Points: 3
    Location: Hampshire UK

    SukiSolo1 New Member

    I have been aware of the Orca plugin pretty much since it came out. AFAIK it will help you quite a bit on generating the curve of areas automatically so you can see what section changes do. As lofting surfaces IS a History feature in Rhino you can simplify changes and reiterate pretty quickly. I'm not sure you will need much more than that as it's quick to give the CofBuoyancy anyway. Try and find someone else whose has used Orca or is still using it - likely better on keelboats and will probably give righting moments etc. I liked Rhino 5 and ran it on a Win 7 box. Went straight to rhino 7 upgrade but jumped OS to Win 11, I think that's why I missed Ver 6 it would not install into Win 7!. I jumped XP, 8 and 10, no biggie.

    It's really important to consider the dynamic of a hull through the range. You will find some that probably have great static figures but bury the nose easily as you can't sink the stern. No CAD system is going to give you that feel. My own 'feel' is that 12 foot boats are hard to get right whether single or double handed especially plane take off and staying on the plane. I've built a couple this sort of length, the second genuinely competitive even after 15 years. At 14 feet plus boats are a lot easier and just go fast enough for it to be far less of a problem. There's a certain small kids rotomoulded boat that took 5 prototypes to get right - proof that small boats are harder design work. It was worth it, the sales have been very very good. If you want another example, the stern of some designs becomes extended with heel - look at 2.4 meter yachts so they suddenly drag water further along the rear sections and extend their displacement speed window upwards. The more different development class boats you can sail the better you understand small changes in design and their effects. Having spoken to at least half a dozen qualified naval architects at the relatively small scale of dinghies what you build is the test prototype. Bear in mind that even here 3mm on a section can be worth 100m in a mile on a reach (I'm pretty sure Jo Richards found that out with his F Dutchman), though I stand to be corrected.

    On getting a smooth shape hull in the UK we have a Class called National 12s and their rules allowed a 4 plank construction when they developed a cheaper alternative to full clinker back in the 1970s'. They went smooth ie not overlapped planks at the same time - so three chines per side plus keel. The designers found how close they could get to a fully cold moulded smooth hull at the time, this is where the 3mm max deviation from a perfect smooth shape comes in. Note this does not stop a deliberate chine... especially aft.

    Currently the hard stuff is primarily in foils and all that entails with airborne hulls, look how fast that changes in Moths.
     
    Jimboat and pironiero like this.
  2. BlueBell
    Joined: May 2017
    Posts: 3,424
    Likes: 1,306, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    Kind of says it all right there.

    So, who's trolling? An accomplished Naval Architect? I don't think so.

    I'm glad you finally found the answer you were "hoping" for.

    Carry-on.
     
    pironiero likes this.
  3. pironiero
    Joined: Apr 2020
    Posts: 285
    Likes: 21, Points: 18
    Location: Pattaya, TH

    pironiero Coping

    Oh wow, thanks a lot!
    I honestly don't know what to say.

    My current project aims for the least amount of chines(i figured 2 is the best option for a light planing Hull, good WS shape on the heel while minimizing the amount of hours for construction) and full flat panel construction, the main rule id like to fit in is a classe950 box rule, although if IMER flies -maybe i make some adjustments and switch to it(although hopes are quite low, given all that I've learned, it seem more like a cashgrab than a proper racing class, the curse of the void between mini 6.50 and class 40 and all.

    That being said there is very little chance I'll actually build it, but a man can dream.
     
  4. mc_rash
    Joined: Aug 2020
    Posts: 243
    Likes: 70, Points: 28
    Location: Netherlands

    mc_rash Senior Member

    Rhino contains all the necessary stuff/commands and provides enough information(area, volume, moments) which is needed to calculate all the stuff related to Naval Architrcture.
     
    pironiero likes this.
  5. Tops
    Joined: Aug 2021
    Posts: 479
    Likes: 143, Points: 43
    Location: Minnesota

    Tops Senior Member

    Is there a website that is the current keeper of the class 950 box rules that can be shared?
     
  6. pironiero
    Joined: Apr 2020
    Posts: 285
    Likes: 21, Points: 18
    Location: Pattaya, TH

    pironiero Coping

  7. Tops
    Joined: Aug 2021
    Posts: 479
    Likes: 143, Points: 43
    Location: Minnesota

    Tops Senior Member

  8. pironiero
    Joined: Apr 2020
    Posts: 285
    Likes: 21, Points: 18
    Location: Pattaya, TH

    pironiero Coping

    There is some movement around this class in [REDACTED], but i won't soil the fun
     
  9. Tops
    Joined: Aug 2021
    Posts: 479
    Likes: 143, Points: 43
    Location: Minnesota

    Tops Senior Member

    It may be more fun to share and share alike here.
    Simple (clumsy, needs work) chined 950 hull in Rhino, exported as VRML into Delftship Free to figure out draft at 2700kg.
    I then added the waterline plane back to Rhino and confirmed submerged volume of hull in Rhino as a cross-check.
    Not a professional, just passing the time at -24C (-11F) weather this morning.

    tops_950_delft.jpg

    upload_2025-12-14_8-50-10.png
     
    pironiero and mc_rash like this.
  10. pironiero
    Joined: Apr 2020
    Posts: 285
    Likes: 21, Points: 18
    Location: Pattaya, TH

    pironiero Coping

    thanks, very cool
     
  11. TANSL
    Joined: Sep 2011
    Posts: 8,029
    Likes: 976, Points: 123, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    I would clarify that this is only correct if you don't need calculations of load conditions, its floatation equilibrium, stability, heeling with crew at side, and list due to waves and wind are not required... (I won't go on to avoid boring everyone).
    In short, for an amateur who doesn't have to comply with any regulations, yes, Rhino will be very useful.
     
    Last edited: Dec 21, 2025
  12. william stokes
    Joined: Oct 2025
    Posts: 146
    Likes: 19, Points: 18
    Location: Australia

    william stokes Senior Member

    Howard Chappel, author, has the best chapters on lofting
    lofting the long lines and sections, should be done everytime to PROOVE the lines, unless the C.A.D dwgs are done by an expert whom you trust
    Chapelle taught me to loft in 1978 building my first 43 footer
    even with proven offsets you need a loft, especially body plan, sections as you will lift floors, frames, brackets, knees beams n frames off of it, there are no short cuts in boatbuilding, only quicker ways, you'll find quicker ways even after 50 years
     
    TANSL likes this.
  13. william stokes
    Joined: Oct 2025
    Posts: 146
    Likes: 19, Points: 18
    Location: Australia

    william stokes Senior Member

     
  14. william stokes
    Joined: Oct 2025
    Posts: 146
    Likes: 19, Points: 18
    Location: Australia

    william stokes Senior Member

     
    Tops likes this.

  • Loading...
    Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
    When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.