Machine Engineering in Grasshopper

unhandled

(Lagemann) #1

Hi,
maybe this is a silly question, but: I am looking for something, which should be the most common thing to get: A proper plug-in for modelling complex machine parts. All I find in “Food for Rhino” is a fuzzy cloud of plug-ins that might or might not be helpful.
As a short explanation: All I want is to design a Chainring (which is not round) - I thought grasshopper might be a good idea because so I can script the whole gearing. However, it turns out that a) I have to do a lot of steps to generate the trim-shapes and -solids and b) the crucial part - the geometry collapses after only a few operations - not to bore, but it is not even possible to get proper chamfers at the tips of the teeth. A boolean operation works well for 43 teeth and the 44th is simply left out for no discernible reason. Not to speak of the possibility to fillet certain edges with a specific radius and then another edge on the same 3d-object with a different radius… I am not expecting Solidworks or CATIA, but something that is capable of some basics… if possible within Grasshopper. I anyone could give me advise I would be massively grateful.


(Michael Pryor) #2

Which Grasshopper are you using? I know the newest versions have fillet for breps and a set of new components for different types of edge selections.

All I find in “Food for Rhino” is a fuzzy cloud of plug-ins that might or might not be helpful.

Food4Rhino’s Grasshopper section is mostly free plug-ins. Many of them hobbies (like my own) so you probably won;t find what you are looking for there. Ones that are actually someones full time job often are on their own websites and cost money, or are not released to the public but are used behind the scenes at consultancy/design offices to remain proprietary (and not give the tools away to the competition).

I donlt know much about jewelry making but 2 I can think of (that do cost some money) is Rhinogold (for Rhino, not GH) https://www.stuller.com/rhinogold and the paid version of Peacock (for GH, has a free version on food4rhino but it has much less components than the paid version): https://www.patreon.com/PeacockGH/memberships

Edit: Dunno why I thought you mean jewelry, anyway same situation applied for machine parts, Some I think of are BoltGen: http://www.food4rhino.com/app/boltgen-manuals-and-help-rhinoceros-windows-and-mac
RhinoGears: http://www.food4rhino.com/app/rhinogears
Gear: http://www.food4rhino.com/app/gear


(Riccardo Majewski) #3

It would be really useful if you share your actual definition or give some pics about it.
" I want is to design a Chainring (which is not round)"
What do you mean?
Not round, because it have teeth? Or because the primitive shape is not circular?
Also, I would suggest you to work as much as possible in 2D, with curves and line, and only at the very last to make solid booleans and fillets.


#4

This seems like a case of right tool for the right job. If you’re making a bike chainring, use a parametric mechanical CAD package. This is basically a textbook case of what they were made for. Without too much work you should be able to make a few parameters drive your whole design.

Unfortunately, I have not found Grasshopper to be very good at creating complex solids. Your problem can certainly be solved in Grasshopper but it would take quite a bit of work. Also, I’m not sure what’s your level of expertise with Rhino. The way you build your geometry is usually quite different from parametric mechanical CAD packages. You usually want to avoid doing solid operations and instead do that work with curves before you even have surfaces.


(IVELIN PEYCHEV) #5

You, right, GH has almost everything to get you started, but you’ll have to spend some time with it to see the value in spending the time with it :slight_smile: .

Unlike Michael, I do not rely (trust) custom plugins, because they may do almost the thing I want but they almost never do exactly what I want. This is why you won’t see me promoting any of the plugins from food4rhino. I prefer to invest considerable amount of time to implement in GH exactly as I want it, than to adapt to what someone had as a vision when he was coding his custom component/plugin.

As a proficient CATIA and basic Solidworks user, I can say for sure you can implement everything CATIA and Solidworks can inside GH. You also have much more control over the input and output (and what lies in between) inside GH. Just bear with GH a bit and you’ll see.

Side note: Read about the history of CATIA / SW and Rhino, they were generally developed for different things. How can you expect that Out-of-the-box they do the same? There’s a reason why it’s called SOLIDworks, it’s meant for machine building. CATIA is a general purpose parametric modeling tool, its purpose is to cover as many industries as possible, and Rhino is a freeform surface modeller and the parametric capability is provided by GH.

I do believe GH will in future be part of Rhino rather than a plugin, but that’s not the case at the moment.


(Michael Pryor) #6

Unlike Michael, I do not rely (trust) custom plugins, because they may do almost the thing I want but they almost never do exactly what I want.

That is why in my opinion plug-ins should be less specific, and more GH like. Meaning breaking down things into methods that have a variety of uses. Probably a plug-in that makes a few specific gears is too specific, but there could be one that lets you more easily make holes, fillets, notches ect. Those are the most useful types of Plug-ins.

Also, I don’t rely on any plug-ins. But def use them if they do something I want to do and use less components. But I do (usually) understand how to make the stuff without them also.

I do believe GH will in future be part of Rhino rather than a plugin, but that’s not the case at the
moment.

It isn’t technically a plugin in R6. Or do you mean eventually it will be more integrated.


(IVELIN PEYCHEV) #7

Oh, it is. It starts in different window, uses goo rather than native Rhino objects.


(Michael Pryor) #8

To me Plug-in means I have to dl it and install it myself.

It starts in different window, uses goo rather than native Rhino objects.

I know.


(IVELIN PEYCHEV) #9

:slightly_smiling_face:

@Michael_Pryor you know IronPython is also considered plugin for Rhino, but its integration is a few steps further than GH.


(Michael Pryor) #10

Take a look at these components for filleting and more complex edge selection.


Screenshot provided by Laurent Delrieu


(Lagemann) #11

Well, thats quite a discussion. And a bit to digest, maybe some of it helps quite well. Implementing stuff sounds interesting - be it a bit of taking a deep dive. Ill yet attach a screenshot of the 2D, for whom ever might have a quick solution - by the way, Yes!, Bike gear, actually super-easy to outperform the stuff on the market, the companies really hoax their customers (did a few part myself, already), yet you need proper software to get milleable parts…


(Tim Stark) #12

Now you need to upload the file and show what you want to do with it and maybe than someone can help you.

Btw. can we stop discussing about the use of plugins? Nobody needs to download them and can decide by himself if he wants to use them or not. Not necessary to discuss in every second thread about it. :slight_smile:


(Michael Pryor) #13

which should be the most common thing to get: A proper plug-in for modelling complex machine parts

It was asked…


(Tim Stark) #14

Yes of course. Was not intended as a criticism of your recommendation. But no matter, I understand that you wanted to justify your position. :slight_smile: