Rhino for heavy surfacing does anyone do V8 motors etc

I’d like to hear anyone’s opinion on your use of Rhino for heavy surfacing. I mean mostly automotive vehicle stuff but not the bodies I am more interested in your experiences doing motors etc. especially the blocks with all their multiple complex surfaces which seem really hard to model. Or if you can think of anything similar model wise.

Do you have a procedure?
What tools do you use in Rhino to surface with?
How much time or man hours do you think you spend?
I came across these complex engine models that are modeled in 3ds max. I’m really impressed by this 3dhorse site that sells engine models at not a bad price. I can’t imagine doing one in the man hours I could buy one for. Unfortunately or fortunately the models there are not what I need for my animation. But please take a look and let me know what you think.

Also do you think 3ds max is better than Rhino for doing these types of models? Has anyone here done complete motors like this? I include a pic and notice all the surfacing what would your strategy be to model something like this?

I am by no means a pro with Rhino but I wouldn’t hesitate using Rhino if I had to draw an engine like that.

I don’t think it is much easier in any other program. I mean, complex geometry is complex using any tool.

// Rolf

Engines aren’t really “difficult” modeling, it’s just lots of it. If this is just for animation, then if you really know what you’re doing you might be able to knock it out faster in Max, but “hard” objects are usually considered easier to model in CAD than “graphics” apps that are made for figure modeling. The biggest hassle is all the fillets.

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It is easier in other software in truly parametric software because of several reasons:

  1. If you model the whole thing, each bolt, nut, cog. You have catalogs of standard parts to choose from.
  2. Assemblying the parts in Inventor, Solidworks and Catia is a piece of cake after that. With engineering connections (face to face, axis to axis, rotational constraint, translational constraint etc.)
  3. Having an immutable axes and origin for each part makes it easier to not make mistakes.

On the other hand, if I did not understand properly and all you need is the pretty looking outer shell. Rhino has no match due to its simplicity. And GH in the armory.


You can find lot’s of informations on google to compare direct modelling (Rhino) vs parametric modelling ( Inventor, Catia )
From what I’ve seen both have pros and con.
Direct modelling is generally faster.
Parametric Modelling is more flexible if modifications are coming up later on in the development process.
So, if your want to develop a new “real” engine for production parametric modelling makes sense.
If you just want to recreate something for rendering direct modelling might be better.
In Rhino you might have a lot more “freedom” than in other direct modellers. You can also add parametric stuff just as you really need it with Grasshopper.
For Bolts you can use Boltgen.
Standard parts in Step format are available on several internet platforms.

As for me, I was thinking of drawing an engine only for display purposes. I wouldn’t think of downloading a 3D model from the Internet if I planned to design a real engine for production … :wink:

// Rolf

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Of course not, except you need standard DIN parts like special screws or bolt, or something from a suppliers catalog…
The part catalogs that are integral to some other programs can be replaced by these online catalogs… like traceparts.com

Hi Jim,
Too funny that’s what I am spending the most time on are the fillets or building up to that stage. One thing I see in max that I wish we had in Rhino is the turbo smooth modifier gives everything a fillet and roundness. But Rhino has so many great tools like you say it’s not that hard but I am finding it challenging and some of the mechanical shapes argh tons of surfaces on different levels and angles there are some brain twists there and then planning a strategy for the fillets.

Hi Jorge,
Thanks for the link I need some of those since there are many of these small parts in the engine. They don’t have native Rhino files but almost all other cad files and obj which is what I need.

Hi Rolf,
What why not :grin:
Imagine all the time it would save.

All good points,

How true, one thing I like in Rhino is I have created a transform space where I can model my parts like this and they transform automatically to the correct location etc. I did use Gh for a while with this but I needed object materials so it was just easier in standard Rhino. I know elefont I tried that not quite there for my needs.


Have you tried https://www.freecadweb.org/ ?
Look at it as open-source SolidWorks/Catia with added python scripting

Thanks that’s pretty cool looking and quite attractively priced.

:slight_smile: indeed.
Btw, if I remember correctly FreeCAD is a prodigy of Dassault Systemes defectors. Somewhere between/during CATIAv4 to CATIAv5 datamodel change.
Update: I may be wrong about this… :thinking:

Here’s a cylinder head I modeled once (in rhino of course), all I can say is that it was a lot of work.


Hi Rolf

Well … I hope that it be easier … :smile:

I never have to draw those things either … but I often see those things, because I have to import them in order to draw plastic trays to carry them.
And I see a lot of surfaces and a lot of fillets … often fillets over fillets.
And in my humble experience, that is not something you do in Rhino without problems.
FilletEdge usually works fine for simple shapes. I mean shapes where Rhino can find an edge for any needed fillet surface.
But when you start to work on very complex shapes, with lots of bends, slopes, and you have to draw lots of fillets there, you soon start to need FilletSrf, and start to have trimming problems.
… Which in Rhino mean a lot of time fighting against tolerances, tiny gaps and so on …

As I said … just my humble experience. :slight_smile:


Well, I have to agree on the fillet problem in Rhino. Yes, that’s an issue. I guess I overlooked that part. But apart from fillets I “feel very free” when modeling with Rhino, compared to parametric modelers (which drives me nuts). :slight_smile:

But perhaps XNurbs can help us out of the fillet trenches? (I was waiting for alternative payment options for XNurbs, but now I only find the price has gone up while waiting). Sigh.

// Rolf

Maybe :slight_smile:

But having to rely on an external plug-in just to fillet quickly feels … weird. :confused:
( At least from the point of view of old time MCAD users. :wink: )

OK, I know, Rhino’s core business is free-form, and fillets are not free-form …
Still, as you pointed out, being able to ‘feel free’ and to fillet properly would be cool. :grinning:



Hi Emilio,
I have to agree I am having a devil of time just getting fillets to work and trying to get g2 continuity is an exercise in head banging. The worst part is the failure of fillets and the old work arounds that one has to do time and again not to mention Gcon on your surfaces themselves. I am humbled by these models.
Thanks for your input.

Hi JD,
Ah the voice of reason, don’t you love how people say it’s not that hard but they never say it’s a lot of work.
Now that is quite nice really well done!
I made covers for the cylinder heads and that alone was no picnic. Any modeling strategies you care to share if you recall what the hard parts were or procedure?

Thanks for your upload and reply.