Using the Loft feature to create irregular pyramids on a cylindrical surface

[valentin.finozzi]

Hi,

I'm trying to recreate this following object:

What I'm doing is a simple revolution as the base, I create an offset vertical plane, draw an irregular polygon and a point on it, project this polygon onto the cylindrical face as a 3D sketch and then use Loft from the projected polygon to the point on the offset plane.

I've had mixed results. While I've been able to create some pyramids I am getting the most varied of errors while using Loft, "not a closed loop", "creating non manifold geometry", "the attempted operation did not produce a meaningful result" or simply "could not build this Loft".

Is there a better way of going about this?

Thanks in advance!

[cadman777]

That looks like quite a challenge!

If someone give me that and asked me to make it in the computer, I'd scan it and then convert it to a surface from a pointcloud mesh. Or else I might try doing it in Rhino3D.

But since you don't have Rhino, maybe you can try using Inventor's Freeform tools?

There are some good tutorials on YouTube for this method if you do a search.

I don't use it, but maybe someone will say you need to use Fusion instead?

[BDCollett]

I agree, that looks like something a freeform tool or modeler would be best for.

[valentin.finozzi]

In freeform all I've tried ends up looking like blobs, nothing like the sharp edges Im trying to achieve, but I ll keep looking into it.

[valentin.finozzi]

While scanning it is not an option, Im not looking for an exact replica but rather to replicate the concept.

Do you think getting the Rhino trial and learning how to do this is anything feasible?

[cadman777]

You can try Rhino, but be advised that it isn't parametric out-of-the-box.

But you can make it parametric by learning a bit of the advanced functions (History).

Also, with Grasshopper you can do amazing things that you can't even dream about with Inventor.

So if you like to do freeform surfacing, Rhino is a very good tool.

Maybe go to the Rhino forum and show your project and ask to see if it looks like it's not complicated to do.

YouTube also has a lot of good videos on using Rhino.

That's where I learned some of the advanced stuff and some of Grasshopper.

[cadman777]

Sorry but I can't comment on Inventor Freeform tool, b/c I don't have it in my older version of Inventor. But I would guess it's a 'trinket' that really doesn't do much, like all the other trinkets that have been globed onto Inventor over the years to make it look attractive in the marketing world.

[BDCollett]

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@cadman777 wrote:

Sorry but I can't comment on Inventor Freeform tool, b/c I don't have it in my older version of Inventor. But I would guess it's a 'trinket' that really doesn't do much, like all the other trinkets that have been globed onto Inventor over the years to make it look attractive in the marketing world.

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I don't think that's fair. It's just another tool and it certainly has its use.

You could call any number of features trinkets if you did not use them or need to.

[WHolzwarth]

Freeform normally doesn't create sharp edges.

I think, Rhino's Grasshopper can do, and perhaps Revit,too. But there's some learning behind.

I'd expect a rather flat learning curve with 3dsMax Noise modifier.

Youtube Video: https://www.youtube.com/watch?v=1-BbOALvB10

[cadman777]

@BDCollett,

I suppose it all boils down to one's perspective and experience.

It's a trinket to me b/c the parts of Inventor that I believe should have been developed have hardly been touched. Some very necessary 'add-ins' have been created by no-names which could have been easily incorporated into Inventor by the developers a long time ago. Yet, they are no where to be found. But instead, Autodesk adds things that only a tiny percent of people would normally use in a production setting, presumably (as always) to catch the eye of prospective customers. The key here is PRODUCTION SETTING.

The fact that they spent most of their development money on AEC (e.g., Revit - a PRODUCTION SETTING) instead of mechanical (i.e., Inventor) for over a decade is proof of that. Let's face it, they invested in Fusion when they could have incorporated that 'tech' into Inventor and made FreeForm a real app that was integrated into Invetor. Fusion vs. Inventor's FreeForm tool, functionality vs. marketing. That comparison says it all.

I'm curious about something:

1. What kind of work do you do in a production setting?

2. Which parts of Inventor do you use day-in-and-day-out?

3. How many years have you used Inventor?

4. What other software do you use regularly in conjunction w/Inventor?

5. What 'improvements' has Autodesk made to Inventor over the course of the years that you use regularly in your production setting?

6. What % increase in production has those tools given you each time the software is 'upgraded'?

Thanx...

[cadman777]

When I encounter this kind of challenge, the first question I ask myself is, Should I do this manually or try to automate it?'The answer to that question depends on how much time I have to waste trying to automate it using iLogic or making a parametric model that has every possible permutation that I might encounter in the real world. Your part is a bit more complicated since it's an art form more than a mechanical object. So the aspect of randomness complicates the process. For the most part, I choose 'manually', even though it usually takes a lot of time to do compared to if I can just press a button and do a little afterwards 'scrubbing' on the model and drawing (that is, IF I already have an automated process for it).

One guy in here I tried to help with a geographical/topographical pointcloud. I used Rhino3d + Grasshopper to do it by looking at tutorials on YT and then using the one that seemed to best fit the scenario. It would be impossible for me to invent the method using GH b/c of the learning curve that I don't yet possess. So I relied on the experience of others who have already developed GH methods to complete the task. It took about 2 hours to learn and 1/2 an hour to accomplish. I would consider that a good use of time, esp. considering there was no other method I could use apart from learning new software or spending piles of money on specialized software. So sometimes Rhino+GH is very useful.

When using GH, the thing I do is think about the procedure involved in accomplishing the task. It's going to be linear and probably have multiple iterations. So first thing I have to do is look at the geometry and figure out what's going on with it. Then figured out how to make each piece of the geometry. Then figure out how to make it using GH. Then figure out how to use the tools in GH to automate the task as well as modify the features in a random way. That takes a lot of thinking and a very good familiarity w/the software (both Rhino & GH). So using GH to accomplish what you want may be a more advanced skill in Rhino. That's why I suggested going to the Rhino forum. Those guys in there are amazing, and very helpful. Whenever I have a challenge in Rhino that I can't solve, I always walk away from that forum learning new things and improving my modeling skills. Learning Rhino better also helps me use Inventor better when I do surfacing and other complicated tasks, b/c of an expanded perspective.

I hope that helps you get an idea of what may be involved in using an automated method for creating the part you want to make with a computer.

[SBix26]

I would try to place vertex points, connect with lines in a 3D sketch, then create boundary patches and sculpt.  If it's really supposed to be a somewhat random feature, then it will be a lot of work (like creating a traditional carved sculpture), but if patterning is a possibility, it might be done in an hour or two.

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Sam B

Inventor Pro 2023.2 | Windows 10 Home 21H2

[WHolzwarth]

Her's a quick test with 3dsMax Noise Modifier.

[BDCollett]

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@cadman777 wrote:

@BDCollett,

I suppose it all boils down to one's perspective and experience.

It's a trinket to me b/c the parts of Inventor that I believe should have been developed have hardly been touched. Some very necessary 'add-ins' have been created by no-names which could have been easily incorporated into Inventor by the developers a long time ago. Yet, they are no where to be found. But instead, Autodesk adds things that only a tiny percent of people would normally use in a production setting, presumably (as always) to catch the eye of prospective customers. The key here is PRODUCTION SETTING.

The fact that they spent most of their development money on AEC (e.g., Revit - a PRODUCTION SETTING) instead of mechanical (i.e., Inventor) for over a decade is proof of that. Let's face it, they invested in Fusion when they could have incorporated that 'tech' into Inventor and made FreeForm a real app that was integrated into Invetor. Fusion vs. Inventor's FreeForm tool, functionality vs. marketing. That comparison says it all.

I'm curious about something:

1. What kind of work do you do in a production setting?

2. Which parts of Inventor do you use day-in-and-day-out?

3. How many years have you used Inventor?

4. What other software do you use regularly in conjunction w/Inventor?

5. What 'improvements' has Autodesk made to Inventor over the course of the years that you use regularly in your production setting?

6. What % increase in production has those tools given you each time the software is 'upgraded'?

Thanx...

---

I agree with you on some of those points, it would be better to improve existing tools than add new ones sometimes. That doesn't change the fact that it's still a useful tool, even if me or you do not use it or may never need to.

As for your questions, is this a job interview? 😄

I don't think that's really relevant. I can have my opinion just like you; someone using the software 13 years out of date.

I no longer use Inventor in a production environment. I did for 15 years in multiple different industries so the tools I used vastly changed.

I now teach and help people use the tools, so I get to see what people are doing.

There are so many improvements that have helped over the years that it would be hard to list. Going back to Inventor 2010 would feel like going back to the dark ages at this point.

[cadman777]

'Job interview'...LOL...good one.

The way I see it, we're in it for the money just like they are (but we don't 'love and serve' money like they do). We give our customers what they want, b/c that's what they pay us for (or else we're out of work). But they don't give their customers what they want, but they still get paid year-in-and-year-out. Moreover, they give their customers what they themselves determine is what the customer wants (which may or may not be true), which is mostly a GUI change year-by-year, just like with AutoCAD back in the 90's. Don't you think there's something wrong w/that picture?

Before SW got totally corrupt like Autodesk always was after the first buy-out, SW at least pandered to their customer base. They were constantly adding functionality to their SW that was useful in a production environment. Granted, they didn't give their customers 'every good thing', but at least there was an adequate showing of good faith. I've not seen anything like it in the MCAD world except with McNeel (Rhino3D).

[BDCollett]

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@cadman777 wrote:

'Job interview'...LOL...good one.

The way I see it, we're in it for the money just like they are (but we don't 'love and serve' money like they do). We give our customers what they want, b/c that's what they pay us for (or else we're out of work). But they don't give their customers what they want, but they still get paid year-in-and-year-out. Moreover, they give their customers what they want, which is mostly a GUI change year-by-year, just like with AutoCAD back in the 90's. Don't you think there's something wrong w/that picture?

Before SW got totally corrupt like Autodesk always was after the first buy-out, SW at least pandered to their customer base. They were constantly adding functionality to their SW that was useful in a production environment. Granted, they didn't give their customers 'every good thing', but at least there was an adequate showing of good faith. I've not seen anything like it in the MCAD world except with McNeel (Rhino3D).

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I am not going to get into a discussion on business models and Autodesk. Welcome to capitalism, I guess?  They provide a tool and if people do not buy it, then they will have to adjust the way they sell it. You have a bee in your bonnet about the subscription service, that's fair but a lot of people just deal with it. You are lucky that you have the ability to use the outdated software while still being productive, new customers do not get the option and as someone who has to deal with them, having people on all different versions of the software is hard enough to support, let alone if they are 10yrs out of date.

The software price is a small cost for a tool to do the job. If it's not, then you might want to look at how much you charge for your time.

We have probably derailed this discussion enough though. Feel free to message me and we can complain about big businesses screwing us over for hours 😉

[valefin1318]

I will try that out. This is not work related but a side project of mine, so time isnt a constrain as much as me getting bored and leaving it halfway.

[valefin1318]

Im amazed you did that with a "quick test", that does resemble a lot the look Im going for. It seems like Im trying to fit a square peg in a round hole by using Inventor for this 😐

[valefin1318]

Right now Ive managed to create an irregular blob of the approximate dimensions I need by using the Freeform relatively easily. I am now trying to get a low poly version out of my blob since creasing the edges doesnt quite get me where I want. Once I figure out how to get the low poly Ill maybe get to streamline the process a bit.

[cadman777]

Great. Unfortunately I can't offer any tips on using the FreeForm tool b/c I don't have it.