Join Paul F. Aubin for an in-depth discussion in this video Understanding the course detail version, part of Project Soane: Recover a Lost Monument with BIM.
- Let's continue with the coarse scale version of our Tivoli Corinthian Column. I'm looking at the shaft right now, and I've built the shaft as a simple blend. So, if you look at what I have here on screen, this just a simple blend object. Now, I chose a blend because classical columns are not straight extrusions. They actually have a little bit of taper to them, called entasis, and it's not a straight taper, so technically a blend is not correct, but we're going to use a blend for coarse scale because it'll be very difficult to be able to tell that it's not tapering the correct amount.
When we get to medium and fine detail, we'll do a more properly-plotted entasis. Okay, so, let's take a look at some of the other views here. In a top view, you can see that there's actually two parameters here now. There's a base diameter parameter and a top diameter parameter. Base diameter is still set to 60, but top diameter is set to 53, and so that's how we're simulating the entasis that we need. So let's go ahead and delete this shaft, and I'll create it over again. So I'm going to go to the Create panel and click the Blend tool.
I'll use the circle, snap right to the center, draw it out to the larger size, select the circle, turn on the center mark, and align and lock it in both directions. Then I'll add a diameter dimension, cancel the command, select that diameter, label it, and I'm going to label it directly with the base diameter. We are working on the shaft now, and remember the definition of base diameter is the diameter of the column, measured at the base of the shaft.
That's exactly where we are. This is the base of the shaft. So, we're going to use the base diameter directly on that circle. Then, I need a top to the blend, so I'll choose Edit Top, go to another circle, but this circle will only go out as far as the inner reference planes for the top diameter. Turn on the center mark, align and lock it in both directions, add the diameter, select that diameter, and this time, label it with the top diameter parameter, and that gives us our taper.
When I finish, and go look in the front view, it's the default height, so it's a little too short, so I'll just take this grip here at the top, drag it up, and snap to that reference plane that I have right there, and lock it. This reference plane is called Top, and as you can see, it's being driven by a height parameter, which is set to the proper height. The only step that remains is, optionally, if you want your coarse scale version to have materials, you can select that shaft, come over here to the Properties palette, and next to Material, I'm going to assign a family parameter.
Now, I've already created one called "Shaft" that I'm going to use for this purpose, but you can always click Add Parameter and create another one if you wish. I'll click OK, and then, when we look at it in 3D, it looks like where we started. So, that's our shaft family. I also have open here the coarse Capital. It's a little bit more complex, not so much more, but a little bit more going on here. There's actually two forms this time. There is a blend, and on top of that is an extrusion. The extrustion represents the abacus at the top of the capital, and then this represents the rest of the capital.
Now, there's two unique things going on here that I want to point out to you. So, it's actually a fairly simple family. It doesn't look so much when you go to Plan View. It looks kind of complicated, but it really isn't that bad. If we think about the extrusion first, and I've got it highlighted there, that's being controlled by the abacus' width, and you can see that goes out to here and here. That's the widest dimension, and that's set at 81. Measuring back from that, here and here, you can see Abacus Corner, and it's set to four, and I'm using that all the way around.
So, if you do it four and four, that gives us a little 45-degree line, and that's our chamfer there at the corner. And I just got this four right off the scanned plate from the Vesta column. So that told me how much that chamfer should be. If you edit this extrusion, the only trick to making sure that this flexes properly, let me go ahead and delete one of these lines and draw it again, is to ensure that you lock the end points of this line instead of the line itself. So, when you go to align and lock, don't align the line itself, because that'll try and square it off, and it'll generate this error.
So I'm going to cancel that. What you do instead is, you do your reference plane, and then you make sure you're highlighting the end point of that line, and lock it. And I want to do that on both sides, and in both directions. Now, if you get a message like this, that says that would over-constrain the sketch, just skip that one. So, okay, cancel. And then go in this direction. Lock it, and this direction, and lock it. So, in this case, it needed me to lock three of them, the fourth one would have over-constrained it.
Once you've done all four, or you've gotten the over-constrained message, you're done. Now, the thing is, if you were building this from scratch, you'd have to do that on all four sides. So, it's a lot of aligning and locking, and you've got to pay attention to which ones you've done and which ones you haven't. But when you're done, it should flex and maintain that chamfer. So if I increase this to, say, 80, and click Apply, you can see how that chamfer gets maintained. Let me go back to 60 here, and click OK.
As far as the blend goes, what's going on here is all the complexity in this blend is buried inside. So, if I select the blend and I choose Edit Base, that takes us into the sketch, and it looks a little busy here, because there's actually one, two, three, four Top diameter parameters, and the reason for that is, instead of one circle, there's actually one, two, three, four arcs. And the reason that I did it that way is because, if I cancel out of here, in 3D, I wanted that nice line there, right on the 45.
If you don't do it that way, then what you're going to end up with instead is something that doesn't look quite right. So I'm going to delete this and draw a circle, just to show you what it would look like. And you can already see there in Plan that it looks a little different, and, you know, that's okay, but it's not really what I had in mind. So, instead, what you want to do is make sure you draw this as arcs. So, I'm going to use the Center Ends arc, snap right to the center point there and draw just a 90-degree piece of arc.
I'll select that 90-degree piece and rotate it 45 degrees, and then you can turn on your Center Mark Visible, and what you do is you take this, and you copy it around four times. Now, you can use Copy/Rotate or you can use Mirror, and then make sure that you take all four of them and put the diameter dimension on them. And when you're done, you get where we started from, which was here. So, that's the trick to getting those nice corners in the corner of that blend and making it look more the shape that you had in mind.
So, the final step is to take these three families now that we have, the base, the shaft, and the capital, and pull them all together into a column family. Now, the end result is right here, and once again, if we just kind of take a quick look at this, there really isn't much going on here. There is two levels. That's probably the most significant thing. So, there's the lower reference level down here, and there's the upper reference level there. And the reason for that is, if I look at the category here, this is set to the Columns category.
So instead of starting with a generic model here, I started with a Columns template, and that gave me the two levels. Once I got that, then, you know, you set up the height here. Now, the other thing is, the column height I'm setting up a little bit differently. You see, the way a column family works is, when you insert it into a project, it will ask you for a base level and a top level. And it will automatically try to make the geometry scale inbetween, if you've locked it to both levels. Now, we want that to happen, but we want each of these three pieces to scale in their own proportions.
So, for the base, that one's placed in right at zero. You can see the numbers over here. Well, the real trick is, you need to come over here to base diameter and link up with the base diameter in the parent file. That will ensure that the parent file is going to drive the size of the child families. And so, that keeps that base of the capital scaling in the right proportion. Now, let me re-add these two, just to show you how that was done.
So I'm going to go back to the floor plan, lower reference level, go to Create, and I'm going to click the Component button. So, you can see the three families are already pre-loaded here, because you saw they were on-screen, and I'll do the shaft next, and snap it right there. Now it's probably a pretty good idea to align and lock it. Make sure you're aligning to the reference planes. So, you see how right now it's trying to select the other geometry? Tab in there and get the reference plane and then lock it, make sure you're getting the reference plane, and then lock it, that keeps it centered.
But if you look at it in 3D, unfortunately, something's not right. You see how it's going right through the base there? Well, easy enough to fix. What I did was I created a Shaft Elevation parameter here which is set to part length times 16 and a half. That just puts it right up on top of the base. So I'll just select the shaft here, and right there, for its offset, I click the associate family parameter, and move that to Shaft Elevation. And you see that will pop it up.
Now, I also need to remember to link up the base diameter, because if I don't, then it won't scale when the rest of the family does. So that takes care of that. As far as the capital goes, if we add that one, we're going to get an error message, telling us that we can't see it, and that message is right there. So, I'll just dismiss that, and the reason for that is because there it is, right down there. So, what I didn't show you about the capital that we were working on a moment ago was that, if we looked at its front view, it was actually built below the level.
And I did that on purpose, just so that we could easily switch to this view, and instead of associating it to this level, we could associate it to this one. And that way, we wouldn't have to worry about building an extra parameter. So, all I have to do is select this capital here, and instead of it associating to the lower level, I'll associate it to the upper level, and it will jump right up there. Now, the final trick here to make this whole thing work is notice that I'm calculating the column height based on some number here, and, if you go under Identity Data, you'll see that there's an additional parameter in here.
Now, this is called the Reporting Parameter. So, let me modify that and show you what that is. If you create a parameter, it's a length parameter, make it instance and check the box that says reporting. A reporting parameter reads the value from the model instead of driving the value in the model. So, what we did here was I assigned this dimension between these two levels. So, when the user says this column goes from level one to level two, this reporting parameter will measure how big that is and then, based on the math right here, it will set the base diameter accordingly, which will, in turn, scale everything else.
So, it's sort of a little chain reaction there. It's the hip bone connected to the knee bone connected to the thigh bone. You've got to get all the parts connected together correctly, but if you do, sort of magical thing happens. If I take this level here and I move it, like maybe right there, do you see how everything scaled down? Except, of course, my capital. What did I forget to do? I forgot to link up the base diameter. And you can see what happens if you forget to do that. But if I fix it, there it is. And so now we have a fully-flexible coarse-scale version of our Corinthian column.
NOTE: Registration for the rendering phase of Project Soane opens in January 2016. Render the Revit or RBX models in your favorite Autodesk software for the chance to win great prizes from HP and NVIDIA.
- Researching source materials and source drawings
- Sketching and modeling architecture
- Setting up the project in Revit
- Modeling overall forms
- Using system families
- Adding details such as columns and moldings
- Creating an interior model
- Rendering the project