Join Dave Schultze for an in-depth discussion in this video Dave's golden construction strategies: How to analyze and model like a pro, part of Rhino 5 Essential Training.
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In this video we'll learn how to quickly analyze almost any designer part for the best modelling approach. And the best approach will ideally be as simple as possible and allow you to make changes quickly and easily. So, I've labeled these Dave's golden strategies. These are things that took me years to come up with and you've got them all in a most nice handy list. Let's start with the top, so this is an example part, we're going to actually build this pretty quickly after we go through the list. Just take a look. Here's my do's, we'll hit the don'ts next. Lot of times I see people staring at the screen getting a little bit confused, not knowing how to start.
The best way to over come that is just make a quick sketch or doodle, so draw it from any view and it can be simple as possible, that usually will get you going. A lot quicker than you'd imagine. Next up, we've talked about this before. But draw the object in curves. Don't just start off building stuff with solids or primitives. Next, as you're drawing in curves, you can try to put Fillets in those curves before you generate the surfaces. Number four, a lot of shapes are a little more simple than you might imagine. For example, it looks complicated in this view, go back to the top.
But we might be able to just, come up with several profiles. And then intersect those, you'll see that in just a bit. Number five look for symmetry, if you see something that's round from one of the views. That tells you, that it's probably been revolved, also if you have symmetry that you can mirror. Definitely draw that axis so you have a little more accuracy as you build it. 'Kay, coming up number six. Look for things that intersect, that kind of relates to the other ones a little bit. And also relate is number seven. Don't try to make things an exact size in one step.
What i recommend you doing is building things like a loft or an extrusion, have em go past where they're supposed to be. Then trim them back, that's always easier than having an accident where you stop a little bit short and then you have a gap. We'll cover this one also. And finally, the last two are kind of related. Any detail, such as a hole that gets punched through or any smaller detail, try to leave that for later. An example would be a hole and we have those too on this model. Finally number nine, the Fillets and Champers. Always a better idea to keep those at the very end, because you can still make changes right up until that point.
But usually, when you get Fillets in there, it's going to be hard to do any scaling or moving. Now, since we had some do's, of course we have to have some don'ts. So these are common mistakes I see beginners doing. One of these, that drive me crazy, is I see people looking at the shape. And they start just drawing every edge they see and somehow hoping that it'll let turn to surface magically later on. So that is, don't trace edges. You want to think about the profiles of those shapes. Next mistake I see people doing is just trying to throw in boxes or cylinders wherever they see a flat section.
And finally number three, don't panic. Modelling is a process. It's not to be perfectly linear. And since you're a designer you are sketching all the time. Your modelling will kind of mimic that process. You'll go backwards and forwards and try different things along the way. So there's no one right answer. Now let's go ahead and look at this shape one more time. We're going to try to build it as fast as possible using most of these rules, not all of em. So here's some geometry. I discovered there were several profiles that would capture this shape really well. So I've drawn a couple of these shapes already.
I'm going to switch over to some of the other views. So notice in the right side view. This was constructed just with a simple circle and then two lines. I trimmed and filetted. So that's the pre-fillitize I talked about. Also from the Top View, this was actually just a Poly Line with a Fillet there. I'm going to show you one more operation. Undo that guy, go back to Perspective by double-clicking. So here's a great way to leverage your geometry, not having to build multiples all the time. You can always copy, and Offset is one of my favorites.
So that's under the Curve Tool menu here at the top. I'm going to select Offset, so it's showing me the default of one, I want to change that distance to ten. That looks about right. Click to accept. So, check that out. I was able to build all the walls. All the way around. Uniform thickness. Not have to do much math. This is important. You want uniform wall thickness in many parts. So, this is, looks like a ten unit radius. And then with a 10 unit wall thickness, that becomes a 20 radius on the outside.
So, let Rhino do that for you. Okay, we've got all the curves. Now I show you the magic. Let's do a couple simple extrusions. Kind of mix this up and use some of the menus here. Extrude Straight. I'm going to switch this to both sides. Now notice if I looked at my geometry, I don't want to Snap to it, this is what's called making it bigger, just have that go way past. Even though I'm in the Perspective Viewport, these lines are extruding correctly. Because they define a flat plane, so this is the only one way they can really go.
Next up, I'm going to extrude these two guys. Right-click and just get that last command. Again go way bigger than you need. Okay now this may look like a big mess but there is some method to the madness. This next process is very, very powerful. This is one of the key things I, I teach to all my classes. We're going to make several splits, and we're going to do forward and then backward. So I'll explain what that is in just a second here. So we're going to split these two objects, watch the Command line.
So I'm in Editor and it said, what's the Cutting Object? I'm going to pick the opposite profile, so if you're reading the Command line, might have to pull it down just a bit, it should tell you that the surfaces were split into multiple pieces, that tells you it was successful. So we can actually click on them just to verify that. So reading the Command line will help speed things up just a bit. Now, I selected these guys, these two and split them to this. So I call this A to B, now we just reverse the process. We're going to split B back to A. Let's repeat the split.
Objects to Split is this one here that's not yet split. Enter, and then we pick these two pieces on the other side. The Command line tells me it was split into three pieces. That sounds about right, but let's investigate. So, all these pieces look like they are properly done. So, I call this entire procedure split, split, throw away garbage. So you've a handy catch phrase to learn or stick on your next t shirt. So we're just going to throw away some garbage, here, and voila! There's a baby inside of there. Let's go ahead and wrap this up. I'm going to go ahead and join this.
These three pieces are now floating. If I hit, ctrl+j is a short cut, remember you can also hit the little puzzle piece over there. And this is what you always want to see when you're getting towards the end of a model. X number of surfaces or polysurfaces joined into one closed polysurface. That means you did your job. Now in just another note, the reason I made these guys intersect to each other, which seems a little bit strange, is we have a guaranteed intersection. If you split both objects to each other, that meant there was an intersection, that also means that they will join up.
So you kind of built an insurance plan, every step of the way. Let's do the Hole Punching next, which should be pretty easy now for you to figure out. We're just going to extrude that curve, actually let's make it solid since the other objects have been joined. To extrude the Planar Curve straight. So there's our Punch Tool. Let's go to the Solid Tools area, to make the punch happen. Here's the Boolean Difference. It's asking for the first surface to subtract from, so that's always the one you want to keep. Enter, and the one you want to punch from, second Enter.
So this complicated shape, almost there not quite, was made entirely with about, what three of four curves? And if I wasn't talking could probably build this much faster and make very very quick changes. Let's go ahead and put those Fillets one. So it looks just like the other one. It's under the Solid Tools. Here's the Fillet. Let's change the radius. I think I'm going to go to like two or three to match the other one. One nice thing about the Edge Fillet is they got the Chain Edges Feature in here.
So, it's just going to run all the way around. Watch this. It's a lot of little pieces that have just joined together for you. So I'm going to accept that, it's going to show you some previews. Right-click to accept those. Finally get one little final preview over here, that looks about right so I'm going to right-click. There's a pretty clean Fillet. So I'm repeating my earlier command by right-clicking in the Command line and then selecting Variable Radius Fillet from the handy list of recently used commands. Radius is the same. You want to hit Chain Edges.
You gotta pick that each time. Goes all the way around. Right-click Previews. Right-click Final. So if you remember that list, this is doing the Fillets and Chamfers last. Let's give these holes, a little Chamfer themselves. We'll change the distance to maybe two. Now, if you don't have the Chain, here's a great little trick. We can just keep picking edges. Everywhere in your file. going to right-click to accept, we get the preview, right-click again.
We just did four Chamfers at once. How cool was that? So I'm going to pull this over. And just do a little quick recap. So we built this entire complicated 3 dimensional and closed solid from just a small handful of curves. Now, we talked about changes. Let me explain how those might happen. Since these curves are already generated. I would go back. And if, for example, this needed to be a little bit longer, I could just grab a group of these Control Points. I am just going to use the Nudge. I can make that just a little bit bigger, or a little bit smaller.
So I want to be careful, if you already got Fillets, you don't want to have those get stretched or distorted. So, there you have it. Turn off the Control Points and move these out of the way. Okay. So take a good look. This is a few years of doing stuff the wrong way, so I hope these are helpful to you in building your projects.
- Why use Rhino?
- Understanding 3D terminology
- Comparing Bézier curves, B-splines, and NURBS objects
- Navigating the viewport
- Manipulating objects with commands
- Creating curves, surfaces, and solids
- Performing basic transformations
- Making solids with primitives
- Extruding curves
- Snapping to objects and planes
- Trimming, splitting, rotating, and copying objects
- Working with NURBS and seams
- Prototyping a 3D model