topic Re: How to model braided rope? in Fusion Design, Validate & Document Forum

How to model braided rope?

mariahagnell — Sat, 11 Jan 2025 10:11:35 GMT

Hello! I would like to model a braided rope. It does not have to be functional but rather just have the appearance. Since what I want to make is a little more detailed than the picture I cannot juust make a pipe and try to make something work with adding custom appearances. I tried making a weave and bending it using unfolding and folding a sheet metal flange as is this video https://www.youtube.com/watch?v=jwvVqswWjfs&t=308s . But it didn't work. Any recommendations would be highly appreciated!

Re: How to model braided rope?

Drewpan — Sat, 11 Jan 2025 10:58:29 GMT

Hi,

Fusion simply is NOT the tool you need to use for this project. It may be possible to come up with something using

the Form modelling tools but it will not be what you want. Fusion is parametric modelling software designed for

CAD. This type of model is about as far from CAD as I can think of. What you need is some kind of free form modelling

software.

The nearest you "might" be able to come up with is something like a braided cable in a bridge, but this is very

different to an actual piece of rope. You might be able to simulate a rope with a pipe structure with some kind of

rope like texture?

Cheers

Andrew

Re: How to model braided rope?

mariahagnell — Sat, 11 Jan 2025 13:17:15 GMT

Thank you so much for your reply. Would you be so kind as to recommend a free form modelling software? Preferably one with student discount or a less expensive one I can cancel after a short time period.

Re: How to model braided rope?

TheCADWhisperer — Sat, 11 Jan 2025 13:58:19 GMT

@mariahagnell wrote:
Any recommendations would be highly appreciated!

@mariahagnell

I would experiment with circular patterns of several helixes (Coils).

Give it a try and post the *.f3d file of your attempt here.

Re: How to model braided rope?

MichaelT_123 — Sun, 12 Jan 2025 00:06:28 GMT

Hi Mr TheCADWhisperer, Mrs MariaHagnell,

Braids ... are a topological object type... of knots family. Generally, they are hard to abstract both physically and mathematically, although some sailors and gifted individuals are quite capable of doing so ... intuitively!. Mathematics behind is very abstract and challenging for most people to swallow.

Is it possible to model them in F360?
I have done some knot modelling, but not braids specifically. Nevertheless, I think the task is not impossible, although it is relatively tricky.

Regarding the suggestion by Mr TheCADWhisperer,

"I would experiment with circular patterns of several helixes (Coils)."

Nope, Queen Geometry is more demanding.

Regards
MichaelT

Re: How to model braided rope?

TimelesslyTiredYouth — Sun, 12 Jan 2025 12:40:28 GMT

@MichaelT_123 wrote:
"I would experiment with circular patterns of several helixes (Coils)."
Nope, Queen Geometry is more demanding.

Nu Uh, I believe you've forgotten a little something called "nested Geometry"

Anyway for @mariahagnell If your insisten on using Fusion For this Laborious task, then I would advice a series of stretched coils, with each individual rope being a sweeped circle, with added details in Blender...

But me personally, I would model something like this within Blender as it's modelling tools would give more flexibility for such a project, unless of course you use Autodesk Fusion MeshMixer...

Not sleepy Regards

Ricky

Re: How to model braided rope?

mariahagnell — Mon, 13 Jan 2025 11:10:32 GMT

Hello! Thank you for your answer. Sadly it is not a simple helix since it bends around the other strends. See images
below of a sloppy loft I manage to do. If you have any advice concering the lofted version it would be appreciated.

Re: How to model braided rope?

mariahagnell — Mon, 13 Jan 2025 11:12:05 GMT

Re: How to model braided rope?

mariahagnell — Mon, 13 Jan 2025 11:25:13 GMT

Hello all and thank you so much for your answers. I've tried different ways and the easiest and best version was doing lofts around around helix sketches. See pictures. What I would like to do now is make a sketch following the center of the strand, see the blue dotted line in the attached. Is there any way to do that?

Re: How to model braided rope?

TrippyLighting — Mon, 13 Jan 2025 12:30:40 GMT

@Drewpan wrote:

Hi,

Fusion simply is NOT the tool you need to use for this project. It may be possible to come up with something using

the Form modelling tools but it will not be what you want. Fusion is parametric modelling software designed for

CAD. This type of model is about as far from CAD as I can think of. What you need is some kind of free form modelling

software.

Complete nonsense!

Re: How to model braided rope?

TrippyLighting — Mon, 13 Jan 2025 12:46:02 GMT

Please share your model. Export it as a .f3d file and attach it to a post.

Re: How to model braided rope?

johnsonshiue — Mon, 13 Jan 2025 17:55:02 GMT

Hi! As experts already mentioned, modeling the braiding in Fusion (or any CAD tool) could be difficult. The most challenging part is defining the path. It is quite complicated. But the following is very easy to do in Fusion. Only two sketches and one feature (Twist Sweep) are needed.

Many thanks!

Re: How to model braided rope?

Drewpan — Fri, 17 Jan 2025 07:38:27 GMT

Hi,

Total Nonsense?

As the person who posted this has already pointed out, a rope braid is NOT a series of

intertwined helices. The braid passes over and under several strands for a start. A bunch

of helices intertwined might visually resemble the braid but it stops there. As @MichaelT_123

has pointed out, the mathematics of ropes, knots and braids is VERY complex. I know

this, which is one of the reasons that I said fusion was not the modelling software for this

project.

Another reason I suggested that fusion is not the software for this project is that if you tell

me you want to model a rope or braid, then I expect the model to have rope like properties

like any other mechanical model I can make with fusion. I can simulate joints and all different

kinds of movement between components and animate them. I don't expect a model of a rope

to be a rigid simulation of the "Indian Rope Trick".

If this is such a trivial exercise for fusion then please show me - I want to learn.

Please model me a three strand rope of arbitary length. I will use your model for various

tests to check it's rope like tendancies. The first test I will do is fix both ends to two moveable

objects and move them closer together and observe how the rope sags between them.

I will also do a dynamic simulation of simply fixing one end and placing a force on the other

end to observe the way the rope tightens up and measure the force on the strands.

I am told that software like 3DS and Blender can model a rope with such properties. I have

never seen one but I have seen similar simulations like a girl's pony tale bounces when walking.

If this is such an easy thing to model in fusion then please show me. I do genuinely want to

learn how.

Only just before Christmas I was toying with how to model a chain for a model canon but I

also needed to simulate a rope and couldn't think how to do it.

Cheers

Andrew

Re: How to model braided rope?

TrippyLighting — Fri, 17 Jan 2025 12:36:54 GMT

Yes, complete nonsense! I did not state it's trivial; it isn't, but that doesn't mean it cannot be modeled!

You should not recommend a different software you don't have any first-hand experience with.

Blender or 3DS Max are polygon and Sub-D modelers; of course, you can model a rope in them.

A Rope like this can also be modeled in Fusion and other CAD software.

The OP asked if this can be modeled in Fusion. Yes it can! Will you have to make compromises on "fidelity"? " Yes, you will. Live is full of compromises and 3D modeling software is no exception, regardless of which particular software you use.

Just because CAD software can simulate stresses on things does not mean it MUST be used to do so for every given project. That's just silly!

Just because trying to describe the geometry of such knot structures in analytical math is complex and challenging does NOT mean they cannot be modeled intuitively. If you read Michaels's post again, you'll find that he stated precisely that!

Clearly, there is a visible repetitive pattern in that rope. The task is now to break that down into its individual constituents and then model those. That isn't any different from any other modeling task. Once that has been accomplished, creating "good enough" geometry is possible.

The OP, judging by the images in some of the later posts, has made significant progress!

I currently don't have the time to decipher that. Below is an object I modeled entirely in Fusion just for fun, just to see if it can be one. This was not trivial!

If a user came to the Forum with this image, would you also advise them this cannot be modeled in Fusion?

Would you even try it yourself?

BTW, I have also modeled this in Blender! Not trivial either 😉

Here's my second piece of advice: Don't give advice if you haven't tried it yourself!

Re: How to model braided rope?

Drewpan — Fri, 17 Jan 2025 14:06:04 GMT

Hi,

I didn't say that this could not be modelled in fusion, I said that fusion is not the

right tool to model this. It seems that is what others have found that looked at it

and thought it was easy to do and discovered it isn't. I can bang in a nail with a

sledge hammer. It works but it isn't the right tool. That was the substance of my

post.

Just because I have no first hand knowledge with different tools does not mean

I don't know some of their capabilities. By your own admission both Blender and

3DS Max CAN model a rope. I cannot model a rope with that software myself but

I do know it can be done, so is my suggestion wrong? Why is it wrong? I have made

a true statement by your own admission.

Microsoft Access is an SQL Relational Database application. I learned how to

program SQL at University. I have never used Access but I have used other SQL

Database software. Would I be wrong if someone asked me about SQL software

and I told them that they could use Access? I have never used it nor do I know

enough about it to advise how to use it but would I be wrong?

Software applications have many capabilities and no, certain uses of them are not

required. However it is not invalid to say that if you are modelling a rope - a flexible

length with certain testable physical qualities, that the model reflects these. Is a

rigid piece of metal that resembles the architecture of a rope really a rope, or is it

a sculpture?

I can model a rope using Michael's mathematical principles, sure. I can have a go at

modelling a rope without them too. I never said it couldn't be done. I suggested that

it would be difficult to do with fully constrained parametric modelling. Sure there is

a regular repeating pattern that can be simulated. It will visually resemble a rope but

not have any of the properties of a rope that other software can create.

Your image is quite striking and it looks quite complex to model. I wouldn't attempt to

model it as I clearly do not have enough experience. I would not point someone

elsewhere unless I thought it was the right thing to do at the time.

In terms of don't give advice if you haven't tried it yourself. I actually HAD attempted

to model both a rope and a chain in a model a few weeks ago. I worked out a primitive

way to model the chain but gave up on the rope as too complex. I could not even see

a way to start modelling a rope with the properties of a rope that I desired for the model.

One of those properties was how the rope sagged when the tension was released that

I asked you to model.

You seem so adamant that I am wrong about this. You create complex geometry in multiple

software applications for "fun". All I am saying is that if it is so achievable then show me.

I do actually want to learn how to do this so I can use it in my own models

Cheers

Andrew

Re: How to model braided rope?

TrippyLighting — Fri, 17 Jan 2025 14:34:03 GMT

Unless you have actual first-hand modeling experience with another tool, you cannot recommend it because you have no idea how to accomplish that task in that other software and cannot assess whether it is easier or "better"!

I have modeled complex geometry in both Blender and several CAD applications, so when I steer a user toward Blander, I can demonstrate how to accomplish a task in Blender. This rope is as tricky in Blender as it is in Fusion. The object I posted an image of had that same characteristic. It was not trivial in Blender or Fusion, but the challenges differed.

As I've described, the difficulty in modeling this object isn't the actual modeling part. The difficulty is recognizing the repetitiveness of the pattern.

Experimenting with Helices, seeing where that fails, and then refining the approach is an intuitive way—at least for me—to accomplish such things. However, whatever app you use, that takes time, time I don't have at the moment.

Re: How to model braided rope?

laughingcreek — Fri, 17 Jan 2025 16:12:55 GMT

@mariahagnell - what is the end purpose/use for the model? that will determine if continuing in fusion or using a different software makes more sense.

Re: How to model braided rope?

mariahagnell — Fri, 17 Jan 2025 16:34:27 GMT

Hello all! Glad to see this topic has sparked debate. It seems like a tricky problem many are interested in learning more about. However, please try to keep the tone civil. I appreciate all your responses and value that they are different and contrasting, as it gives me a better understanding of the problem's complexities and lots of inspiration on how to move forward!

As for those who wondered if I can share the file or if I’ve made more progress, I’m afraid I can’t do that right now due to a confidentiality agreement. Hopefully, I can return to this post later!

That said, I did "solve" it after many, many hours. I ended up using my lofted "strand" as a guide and then used the 3D sketch tool to manually create a sketch that rotated as well as curved through different planes. This allowed me to give the braid the look I described in my original post – resembling strands braided with small pearls on them, using a simple pattern on path. I’m sad that I didn’t figure out a faster way to do this, but I’m happy with the finished result!

Thanks all!

Re: How to model braided rope?

TrippyLighting — Mon, 20 Jan 2025 19:18:53 GMT

For those that are still interested, the screenshot in the initial post came from a YouTube video that explains how this braid is created. THe best way IMHO is to replicate this with actual cords. That will then inform how this can be 3D modeled:

Re: How to model braided rope?

TimelesslyTiredYouth — Thu, 23 Jan 2025 19:39:09 GMT

Thank you! very useful.