Rhino's linear/destructive workflow is a major pain! Rhino6 wishlist


#1

Wish list:

  1. Design tree
  2. Better filleting
  3. Ability to enter dimensions into properties
  4. Constraints/mates

The most glaring weakness of Rhino is it’s linear workflow. Modeling a part and realizing 30 min into it that you’ve made a mistake or need a change means either undoing the last 20+ steps of your process or starting over from scratch and losing a huge amount of time. On a large model… I don’t even want to think about how much time is wasted having to do this! I can’t even change the size of a circle without the gumball! I should be able to click on an existing circle and type in the diameter shouldn’t I? Seems pretty basic. The design explorer in Alibre (and pretty much every other CAD software) allows me to make changes at any time to any part because of it’s non-destructive nature. (see pic)

Fillets! OMG what is with Rhino and fillets!!! Rhino is god awful at fillets! Fail, fail ,fails at the simplest fillets! I spent half a day trying to fillet this in Rhino! After realizing the fillet tool wasn’t going to work, (with every possible setting) I tried blending surfaces, exploding and filleting surfaces, you name it I tried it. I gave up trying to fillet this in Rhino and exported it out to Alibre Design. 1 min… done!

I’m finishing this in Alibre and leaving Rhino for the surfacing work only from now on. Rhino is amazing at most things but there seems to be some glaring omissions.


#2

Would you post a sample file?


#3

cover.3dm (208.8 KB)

It’s the valve cover for a Wright Cyclone 9. I need big fat smooth fillets.


#4
  • Explode–>Shrinksurface
  • Cplane_object (set it to Top surface)
  • Duplicate Top boarder and offset the output curve as desired.
  • Extractiso from top surface and go to elevation view
  • Offset that curve in elevation view.
  • Extend the curve and cut the object…
  • Splitedge at sharp corners… and blendcrv between to edges. shown in the image (the red curve)
  • Extractisocrv, following top blendcrv

Bot is the same…

Test.3dm (255.6 KB)

and go on…

Roughly like this

See If i can demo it after Im back…


#5

I see where you’re going and I’ve already tried it. I did try doing something similar. Extracting the top surface, then shrinking it and doing a blend. It brought new challenges and promised to waste even more untold amounts of time. I appreciate your effort tho. :smile:

The point I was trying to make is that we shouldn’t have to go to such lengths for a simple fillet. I could keep working at it in Rhino and spend hours on it. Each time it’s not perfect having to start all over again, or I can hit one button in Alibre (or OnShape or whatever), enter the fillet size and be done.

The other point I was trying to make is not having to start over every time it’s not perfect or a change is required. In any other CAD if I’m not happy with the fillet or anything else I just hit the edit button. I can go back to any part or feature (fillets, extrude, etc) and change it at anytime. In Rhino you start over from scratch each time. It’s a linear workflow. If I need to change something I did 20 min ago I either hit undo fifty times (losing 20 min of work) or scrap it and start over. You don’t have this problem in Alibre or other CAD’s with the design explorer.


#6

You’re grossly overestimating how easy this stuff is in other software a lot of the time–just last week found myself watching Solidworks “wizzes” futzing around trying to make simple edits to some sheetmetal parts and it’s like okay I’ll just change this number whoops the sketch is broken, whoops I have to add an infinitesimal straight section to this bend to get it to work, whoops those holes are aligned with nothing, I could have remodeled the whole thing from scratch faster. It’s great when it works, but when it fails you’re screwed, while you could have taken the incomplete result from FilletEdge in Rhino, repaired it in a couple minutes, and trimmed things out.

Your model failed to fillet because of a very specific case that Rhino’s filleter can’t handle yet, where a surface gets completely removed by the fillet. Three of the large cylindrical cutouts have their surface seams in juuust the wrong place to make this an issue. I extracted them, untrimmed, and used SrfSeam to relocate the seams, and after retrimming it worked fine with a 0.2.

Rhino’s fillets are better than they used to be, and it’s reasonable to extrapolate from the simple ‘solid editing’ features in V5 that they will probably eventually add something for fillets. There are no plans for Rhino to turn into a Solidworks knockoff.


#7

Try this… I guess you missed this step.
When you blendsrf, turn the continuity setting… In other words, use multiple surface blend.


#8

Actually it is that easy. I wasn’t having problem with the sketch and even if I was, other CAD programs are parametric. If I change the sketch it updates the part too.

My point exactly. How many steps and time it took in Rhino compared to hitting a button in Alibre. Also the fact that if you don’t get it perfect then you start over from the beginning.

Well there’s a reason all CAD and most mesh software share many features. That’s like saying Rhino shouldn’t have extrude because Solidworks does. Sure, there’s way around not using extrude but you have to admit it’s pretty handy. Why shouldn’t Rhino have a design explorer? I can’t believe there’s one single Rhino user in the world that likes to start a part over and over again until it’s perfect. Wouldn’t it be handy to be able to change to anything at anytime?


#9

No you don’t, I fixed it in a few minutes. It wasn’t one button, but at least I know if it does fail I have the ability to fix it.

Rhino exists precisely because some kinds of surface creation and editing are impossible or absurdly convoluted within the confines of parametric modeling, which your engine part here is not an example of. The CAD software you are comparing it to is primarily designed to make large assemblies of lots of relatively simple parts defined by their relationships–mechanical design–that’s not what Rhino is for.

You’re only able to “change anything at any time” if you’ve set the model up right in the first place, which usually takes about 10X the time to just build it from scratch in Rhino.

Of course Rhino does have some limited history ability, which in one example I used to set up a ‘parametric’ shape for a convoluted engine intake that was previously created in Solidworks that I could edit so much more easily the client’s reaction was “Are you kidding?” And don’t forget about the whole Grasshopper thing.


#10

This was one simple small part. Imagine a few minutes x50 for a large model. I need to hit the fillet button, type in the number, hit enter and move on.

Agreed, that’s why I purchased Rhino. I knew I’d be giving up some things, like mates and assemblies to gain Rhino’s huge advantage in organic and flexible modeling but I’m realizing that neither is an absolute solution on their own. If it’s even possible at this stage, if McNeel could add a design explorer, Rhino would be absolute killer.

I’ve never used Solidworks so I can’t say how easy or difficult it is to use but in Alibre I wouldn’t have had to do anything special other than to draw out a sketch and extrude it. Same as in Rhino.

I know eh? :grinning: So much to love about Rhino but some days it makes me want to throw my computer out a five story window too. :laughing:


#11

Right. But what if the side are gently rounded also in the extrusion direction? (extruded along an arc)

I teach both Rhino and parametric and when you have to deal with smooth geometry anything is better than Rhino3D


(Wim Dekeyser) #12

I get like that when I’m about to make production drawings… :wink:

And fillets, well, yes, the old rule applies: only put in fillets when you’re almost done with the design.

But a parametric history tree where the success of your next feature depends on whether a feature 35 steps ago provides for it - no thanks.

That is not the way the industry is evolving anyway. Nowadays it’s all about Direct Modeling, Synchronous Modeling, parametrics-on-the-fly [, and perhaps the Alibre tree provides for something like that (?idk)], where the big ones provide these tools as an alternative to the more traditional way of modelling. And most of the time, I feel that Rhino provides enough flexibility to achieve extensive design changes without having to start from scratch. True, it’s by no means an automated process but to me, that automation typically comes at a price that is too high. Solidworks, Pro/E, Creo, NX, I’ve used them all and chances of a PC landing on the pavement outside greatly increase during these moments.

But that’s really just my opinion…
(and my vote to prioritize other things first)

BTW:

Check ModifyRadius.


#13

I hope Rhino will stay non-parametric. I don’t need the second Solidworks on my PC. I use both programs for different jobs.


#14

Here is my attempt
.cover-2.3dm (1.4 MB)

First fillet by FilletEdge, then, after boolean difference, I had to use FilletSrf, adjust lower edge of fillets, join them and Trim the solid by their Borders, and finally Join anything together.
It did not take too much time, but … yes, I think it could have taken even less, if Rhino’s surface commands had been more powerful.