An attempt to model a ship hull in software.....

[Richard Dunn]

If you guys want to  get started I can vouch for this training.

https://rhino-3d-classes-from-beginner-to-advanced-lev.teachable.com/p/rhino-3d-v6-xbow-ship-modeling-and-rendering-with-vray-level-2

[Kevin-the-lubber]

Well, I'll be coming to it as a beginner and, unless I've found it especially easy to pick up, I'm more likely to need time to work through the 'lesson' first in order to know what questions I really need to ask so as to avoid taking us down rabbit holes. So personally I'd prefer both (greedy!), a video followed by a Q&A. But that is just my wish list and I'll be happy to fit in to your preferences Richard.

 

I'm not at all bothered by the choice of ship, but in learning the techniques and principles. They should be the same whether it's wood or steel (shouldn't they)? The areas where F360 (or I) seem to struggle most are compound curves to a specification i.e. lofting using dimension-bound multiple rails. It can clearly be done, that's apparent from the start-up splash screen alone, but, as it's so central to shipbuilding I'm keen for that to be a straightforward, predictable process rather than an exercise in frustration.

 

I've only really used two 3D programmes, F360 and Tinkercad. Chalk and cheese in many ways but I'd still encourage new starters to explore Tinkercad, if nothing else it has the easiest ever learning curve, you'll have a bit of fun and come to understand what you need by way of a 'professional' 3D modelling programme. I have Freecad and Solid Edge (Siemens) but haven't used either. From forums, Freecad still seems to be a work in progress, Solid Edge just looked like another big learning curve. At some point I should also give that a fair test. I think what I'll do now is develop a couple of test pieces, the predator and maybe the stern section of the Victory hull from McKays drawings. That should test the capabilities well enough.

 

It goes without saying that I think 3D + home printing is going to become a core part of modelling in future. I doubt it will entirely take over as there is such joy in making things by hand, but there comes a point where 'the machine' does it better. Fifty years ago I started out my working life as an apprentice sheetmetalworker. Our factory made big industrial machinery and I became very skilled at pattern development as everything in sheetmetalwork, rather obviously, starts out flat. Square to rounds, cones off cones, 'chine hull' shapes, you name it, I patterned it and made it. Five or six years later I saw my first CNC. It came complete with a man in a white coat, rather than blue overalls, who was paid a fortune to programme it. Within another five years us tradesmen were doing the programming and operation as part of the day job. For me the future was obvious. Pattern development is mostly just trigonometry (I even wrote a programme in Excel to get the pattern coordinates for a square to round by plugging in the basic dimensions). These days I doubt anyone other than in small, custom shops does pattern development by hand.

[Richard Dunn]

Yeah I know its tempting to want a ship you need or have some interest in but the reason Cutty Sark was pick is it has a number of things you need to watch out for that will set you up in good stead.
Guys don't freak out, its not actually that hard if you follow the right order and procedures, I have done this so long its second nature and even when I taught myself it did not take long.
The Cutty Sark has the following points that make it a good subject.

 

No actual as built lines exist
All Lines are measured from survey(close but not 100%)

The plans by NVM are superb and I will use them as they are works of art and inspiring  but you will see how to assess errors and correct.
The stern is of the overhanging counter type, which is the most tricky to do.

You will  learn how to take lines from lines plan and also from a scan , not much different.
How to fair station lines and then how to fair longitudinally.

How to develop true shapes of plates like the bulwarks around the stern

How to set out planking on a hull.

 

I will do it in sections so you can take your time

 

 

Edited October 28, 2021 by Richard Dunn

[Richard Dunn]

I did consider HMS Victory Kevin but its about as hard as it gets and not for the faint hearted.
I  also thought about Sovereign of the Seas now the book is out.

Its awesome, I bought it a few weeks ago

Edited October 28, 2021 by Richard Dunn

[Egilman]

Well I just signed into art station, looks impressive....

 

Personally, I can do pretty much anything but realtime... that's a non-starter for me....

 

I've acquired the latest Rhino available short the maintenance updates 7.11 I think it is.... And I hear that Rhino 8 is in beta testing now...

[Richard Dunn]

Realtime is really more about the texturing and materials nowdays, polycount is able to be quite high, of course you don't abuse it but yeah the baking from high to low poly is the only real difference.

I use Modo  and Maya for most of my Polygon modelling but incorporate rhino quite often in that to.

Edited October 28, 2021 by Richard Dunn

[Egilman]

Ok I just hooked up My account at Linked in and am going to run the essentials course for Rhino 7 once I get it installed....

 

Just getting ready.....

[Egilman]

14 minutes ago, Richard Dunn said:

Realtime is really more about the texturing and materials nowdays,

And those subjects really don't interest me, modeling is what I like and will be taking it straight to 3D printing.... Just looking for the easiest and fastest way to model accurately so I can scale and print....

[Kevin-the-lubber]

24 minutes ago, Richard Dunn said:

I did consider HMS Victory Kevin but its about as hard as it gets and not for the faint hearted.

That almost had me laughing 😂. Two things, or comments, particularly made me dig my heels in on the Victory, bearing in mind this is my first foray into proper modelling. The first was probably on this or another forum many years ago, words to the effect that beginners are doomed to failure if they take on the 1:100 Victory as a first ship. The other was on an F360 forum when I was struggling with one part or another and showed a picture of what I was trying to do (the stern section). I could almost hear the incredulity in the voice of the old hand as he wrote "well... it's possible, but probably not what you want as your first project". They are both absolutely right of course, but at that the first point I'd just spent about £100 for the kit and I was damned if I was going to admit my error of judgement. By the time I got to the F360 comment, £100 was feeling like small change and whether it was my first or last project had become irrelevant, my course was set. That's not to say I will ultimately prove either commentators wrong of course, I have rather a long way to go yet.

 

Fortunately or unfortunately I still don't understand enough about 3D to appreciate why Victory would be harder than, say, the Cutty Sark; after all they are all just lines on a screen, aren't they 😊.... But this time I will heed the advice and avoid the despondency of trying to bite off more than I can easily chew.

[Richard Dunn]

I will explain why Kevin

Not Victory as such but any of those  old ships of war have one very distinct feature in the lines that negates the way we modern designers do our job, normally we have single curve to deal with from sheer to keel or worst case sheer to flat of bottom where it meets the tangent of the rise of floor either way we can fair that curve easily but the old ships like Victory's Station lines are not "Fair "by our standards today but rather comprised of a series of arcs and curves that make a smooth shape but its not fair by our terms today, so every time we have to make corrections to a station we cant just adjust the waterlines and re section those to create new station because there are tons of subtle nuances in between those waterlines that make it very very hard, The stern and bow are not that big a deal, its the actual section shape.
I hope that makes sense

Edited October 28, 2021 by Richard Dunn

[Richard Dunn]

In saying that the books that have lines that have been recreated in cad already  like  Alan Mcgowan's you could safely trace and get a pretty good result but you have to happy with very minor defects in surface but meah... lets face it once 12 inchs of timber planking and wales is on and adzed it does not really matter.

Edited October 28, 2021 by Richard Dunn

[Kevin-the-lubber]

I think I know what you mean. In my language, when modelling the side galleries I ended up using two arcs joined at a tangent for each profile of each segment, as you work up the gallery, 9 segments in all. This means the vertical 'curves' - sheer curves I guess - constantly change from where it meets the stern to where it means the hull, as well as having 9 different horizontal(-ish) curve profiles. And editing any curve is likely to have a knock-on effect. I think this is why I have a small section of 'un-fairness' despite taking pains to make the curves themselves smooth.

[Egilman]

4 minutes ago, Richard Dunn said:

In saying that the books that have lines that have been recreated in cad already  like  Alan Mcgowan's you could safely trace and get a pretty good result but you have to happy with very minor defects in surface but meah... lets face it once 12 inchs of timber planking and wales is on and adzed it does not really matter.

And we have the scale factor to deal with, we are working at much much smaller sizes of parts where minor discrepancies could become a major issue in larger models, in smaller ones they are much less so....

[Kevin-the-lubber]

I was being a bit tongue in cheek there, falsely implying that drawing one line is no more difficult than another. If only it was so. Though perversely, sometimes that's not a bad mindset to have, it sees you having a go at something you might otherwise shy away from. I have a careers worth of succeeding because I knew no better! It's funny how age and experience see you become less (over-)confident, isn't it, you'd think it would be the other way round.

 

I think I'd treat any transposed drawings as no more than starting points, sometimes good, sometimes bad. Back in the day, the drawing office would sometimes give us full size plans and try to persuade us to just dot punch through the drawing. Never happened. I'm not so sure about the scale effect, even at 1:100 the eye picks up all but the smallest anomaly. And if I went on to model the Cutty Sark I'd probably go for slightly larger than 1:100, maybe 1:75, just to gain a few fractions of a millimetre on very small parts and detail and give the printing a better chance.

 

Turns out my little bit of un-fairness is happening in either the slicer or printing. No hint of it in the soft model. Printing is the chief suspect, that it's developing a bit of a warp that gets corrected further up, and needs some strategic support.

[Egilman]

Kevin, it isn't the drawings just like it isn't the tools, in the case of the drawings, once they are complete they become a tool as well....  No matter how accurate the drawings are it is the information they convey that is what is important... the picture can be a bunch of scribbles without a straight line in them, but as long as the dimensions are correct, what is built will be correct if the craftsman knows how to read and interpret them.... you know this, I know this and I'm sure Richard knows it.... 

 

I'm going to prove it with a horrible bunch of drawings out of a fairly crappy BoGP.... What gets me is how many in documentation don't even know how to read what they are in charge of taking care of... Good drawings are better, true, but as long as you know how to use the datum on a drawing it's line accuracy doesn't matter...

 

I do a set of drawings for a customer client or boss and they could generally tell me what it was by looking at the pictures, but that is about all.... (some of them could only read it out of the title block) But telling someone to just use the drawing as a template? Wow!

 

The scale effect at the scales we normally work at is insignificant, but when you start bumping up to 1/25th of even 1/35th scales it becomes an issue...

 

Your printing issue is probably a lack of supports for a resin printer and probably a touch of under exposure leaving the resin just a bit too soft... If there is no hint of it in the software then the slicer works from the same mesh, highly doubtful the issue is there...

[Egilman]

Right now I'm sitting through a fairly boring hour of a two hour course on the basics of Rhino, it's interface and how to draw primitives... I suspect in the second hour they will get into more interesting things.... {chuckle} Nothing like starting from the beginning....

[Egilman]

6 hours ago, Richard Dunn said:

Yeah I know its tempting to want a ship you need or have some interest in but the reason Cutty Sark was pick is it has a number of things you need to watch out for that will set you up in good stead.
Guys don't freak out, its not actually that hard if you follow the right order and procedures, I have done this so long its second nature and even when I taught myself it did not take long.
The Cutty Sark has the following points that make it a good subject.

 

No actual as built lines exist
All Lines are measured from survey(close but not 100%)

The plans by NVM are superb and I will use them as they are works of art and inspiring  but you will see how to assess errors and correct.
The stern is of the overhanging counter type, which is the most tricky to do.

You will  learn how to take lines from lines plan and also from a scan , not much different.
How to fair station lines and then how to fair longitudinally.

How to develop true shapes of plates like the bulwarks around the stern

How to set out planking on a hull.

 

I will do it in sections so you can take your time

 

 

No sweat Richard, it's all good, I suspect that coming out the other side I'll be able to figure out how to model the other hull types, they are all basically built the same way, just different in the details....

 

As far as videos or recorded live sessions, both get the job done, my experience is videos work better than live sessions (as long as they show all the steps) but I can work with either... That experience comes from watching too many Autodesk University web casts that feel like a waste of time wondering what I learned from my investment... I haven't given up on ADU webinars yet, but they are the last place I go to actually learn something....

Edited October 28, 2021 by Egilman

[mtaylor]

RIchard, I'm late to the party as usual.   Might I suggest think about doing the live session and recording it?   The recorded part can then be uploaded to Youtube or anywhere else you like.  

[Haze Gray]

Count me in on the Rhino session as well (whether live or video).  Question on Rhino - is it mostly just for modeling or does is also have a workspace similar to F360 & SW?   When I'm working on a model for 3d printing there's a lot of tools that I use to align, cut, combine, offset, etc on solids.   F360 isn't the best when it comes to the creating the model but it feels pretty strong in the CAD arena. 

[Egilman]

4 hours ago, Haze Gray said:

Question on Rhino - is it mostly just for modeling or does is also have a workspace similar to F360 & SW?   When I'm working on a model for 3d printing there's a lot of tools that I use to align, cut, combine, offset, etc on solids.   F360 isn't the best when it comes to the creating the model but it feels pretty strong in the CAD arena. 

It has all that and more HG, if there was a good way to learn it, (a decent set of serious tuts available) I would have been using it a long time ago... It natively opens in 4 view mode but that's just one click away from becoming a one screen show... And the interface is fully configurable...

 

It feels a lot like, (I hate to say this) like the Autocad user interface.... If you've been doing cad for a long time it will be like old home week.... If your into rendering it uses the VRay rendering engine which is also top of the line and it offers a full range of export options.... So what you do is fully transportable to any other software you might like... Some of the stuff it does and no other software is developable surfaces, flatten surfaces/objects into patterns for cutting, (paper model designers love that one) Too many to list them all...

 

If your familiar with and like general cad software, you  will like this...

 

[Old Collingwood]

Sorry for the delay brother  - I am here at last  - so good to see you making a  start  with this  - I  see you are trying another version, I will follow along as it would be Brillaint to see you go from 3D  design to  printing.

 

OC.

[Richard Dunn]

Just a tip, if you use image planes don't use the background image planes, I know it sounds right but you can only have one per camera and cant scale in 1D

Type picture and choose picture from command line, this will let you load and image, as many as you want and scale however

[Richard Dunn]

Another is curve from 2 curves
Think this, you have profile and plan you trace the sheer outline in plan and trace the sheerline in profile, 2 separate curves, but you can select both and it will create the result which is what you want, but it needs to be optimised and it will be point heavy

[Richard Dunn]

I would recommend tracing body plans with  curve interpolated points use a few points as you can to get the shape and then play with analysis /curve curvature graph and practice fairing curves, plenty online about what is and what is not fair, but think of porcupines as exaggerated curve of the curve

click and hold on this button and pick second one

[Richard Dunn]

Oh and go  into settings/ modelling aids  and set you nudge to arrow keys, use small increments as you need
going to be on CNC today but will check in after each sheet

Edited October 29, 2021 by Richard Dunn

[Egilman]

1 hour ago, Old Collingwood said:

Sorry for the delay brother  - I am here at last  - so good to see you making a  start  with this  - I  see you are trying another version, I will follow along as it would be Brillaint to see you go from 3D  design to  printing.

 

OC.

Good to see you here brother, I'm going to do this come hell or huge water.... {chuckle} This is the future of modeling I think....

 

Welcome aboard....

[Egilman]

1 hour ago, Richard Dunn said:

Just a tip, if you use image planes don't use the background image planes, I know it sounds right but you can only have one per camera and cant scale in 1D

Type picture and choose picture from command line, this will let you load and image, as many as you want and scale however

Thank you for this, I just finished up the essentials course and it explained a few thing which is good, but not anywhere near enough... I was just going to go looking for the method to get images into the view screens, this is right on time....

 

1 hour ago, Richard Dunn said:

Another is curve from 2 curves
Think this, you have profile and plan you trace the sheer outline in plan and trace the sheerline in profile, 2 separate curves, but you can select both and it will create the result which is what you want, but it needs to be optimised and it will be point heavy

He covered this a little bit, and definitely explained about using as few curve point as possible to have an optimized surface, in fact he drove the point home....

 

1 hour ago, Richard Dunn said:

I would recommend tracing body plans with  curve interpolated points use a few points as you can to get the shape and then play with analysis /curve curvature graph and practice fairing curves, plenty online about what is and what is not fair, but think of porcupines as exaggerated curve of the curve

click and hold on this button and pick second one

Curve analysis, he touched on this but didn't go into detail, I'll need more info on the technique....

 

1 hour ago, Richard Dunn said:

Oh and go  into settings/ modelling aids  and set you nudge to arrow keys, use small increments as you need
going to be on CNC today but will check in after each sheet

That's one of the first tips he made and the need is easily seen.... Besides all the other software I've use uses the cntl/alt/shift keys for screen movements, so this is making the Rhino screen view controls conform to the controls I already am used to... And makes the arrow keys much more useable.... (which they aren't in the other softwares)

 

Thanks for the tips Richard, they are timely and right on point.... Invaluable really...

[Richard Dunn]

All good?
Me I am struggling to contain myself, I only have 4 6.5mm sheets to cut and framework is ready to assemble...but I'll be good.

Edited October 29, 2021 by Richard Dunn

[Kevin-the-lubber]

Forgive the questions that would be answered by simply downloading and getting stuck in but I’m waiting until I have a clear desk before starting the time limited free trials.
1. Do both Rhino and SW have the design history function like that of F360? Can you easily re-order the sequence of commands like you can in F360?

2. I’ve read that Rhino can be a PITA for complex filleting - true or false? F360 can be hit or miss there too.

3. My biggest gripe with F360 is how it handles ‘failed’ commands I.e. when it can’t do what you’re asking of it; too often it locks up for a very long time and ultimately crashes. What happens in Rhino and SW? 

4. How do Rhino and SW compare to F360 in terms of the graphical representation of the model? I have to say, I like F360 in this respect.

5. How do they compare in terms of processing speed? F360 can become very, very slow as the model becomes complex and the timeline grows.

6. Ive read that you can import / export between e.g. Rhino and F360. Does that mean you can move it in and out of each package for different stages, or does it become a mesh? I thoroughly dislike the import mesh function in F360, for me it’s a last resort.

7. Are there particular functions of either Rhino or SW that would be naturally important to ship modelling, that perform poorly? Things where, like in F360, you learn through experience to do it this way rather than that, even though the latter might be the more obvious path? For instance, projecting to a surface in F360 will often require that you edit the projected lines afterwards, in order to be able to surface them. (Sometimes the projections don’t join properly). Or using pattern - almost fatal to pattern in the sketch, fine on the model, so you learn to make the model of the pattern and project back to a sketch, if the sketch is what’s needed. At least that’s how I do it.

8. The discussion so far implies there’s very little forum-type help for Rhino. With F360, when I’ve got stuck I have usually been able to get free advice fairly easily from other users. What is that like for Rhino and SW?

[Egilman]

That's my one complaint about Rhino Kevin, knowledgeable support, when you can find it is priceless....

 

What Richard is offering here is priceless IMHO..... You will have some support from McNeel but it's like all such support, they are the software writers, everything is simple to them..... as far as interoperability between softwares, I use file export for all transitions between packages. my preferred file type is .obj... Ancient I know but the most stable.... And all three export that file type....

 

SW has good support, good forums, good training and more tuts all over the net than you can imagine, they run from very low grade to education grade and that is only the free ones.... The paid ones are similar but a step up in quality..... Heck, they are teaching SW in high schools and community colleges....

 

As far as usability for ship modeling, SW does have a few issues I've ran into.... Especially on intersecting compound curves when you need them to stich together, it can get to the point where it says the surfaces are stitched but in reality they are not... The common resolution/workaround is to extend the surfaces past each other and trim them off at the intersection, but that doesn't work reliably... (the gaps remain) You then have to go searching through the model to find the gaps and close them individually.... It's why I haven't finished the Predator in SW...

 

Rhino I believe has the ability to show you where the gaps in your solid model are and point them out for fixing....

 

SW has nowhere near the number and complexity of issues F360 has though... And it does crash once every blue moon but it's recovery routine is very very good....

 

Rhino, as far as it goes, I would defer to those who know cause I plain flat don't know anything... (the long and the short of it)

 

I judge the order of issue level between the three is thus... (based upon my limited experience)

 

Worst to best...

 

Fusion 360...  Solidworks... Rhino.....

 

I'm already at the point where I will not bother with F360 any further, heck it couldn't handle a basic chine hull which was easily done in SW, on an identical machine, I've already shown that.... And from what I have been reading a basic chine hull built from curves is childsplay in Rhino.... I want to see what it does with the superstructure of the predator...

 

Once I get my feet under me in Rhino, I won't be looking back.... And there I run into my main problem with it, good accurate info... I will keep up on SW as another tool in my box for stuff it is very good at but my hard modeling for model making will be done in Rhino....