Join Paul F. Aubin for an in-depth discussion in this video Understanding the medium volutes, part of Project Soane: Recover a Lost Monument with BIM.
- In the previous movie we looked at the abacus and the drum and we saw how we were using a rig of reference lines and reference points to control parametric relationships and keep the shape of this form, which is probably easier to see here in Floor Plan. But the shape of this form has that star shape to it. It's all passing through reference points and that's what's keeping that form. A similar strategy is employed with some of the other families here.
The flower here is actually quite complex. It actually turned out to be a little bit more complex than I liked, and I've chosen to go a different route with the flower on the fine detail version. So we'll save that for a future movie. But you are welcome to open it up and take a look around. Some of these others are a little bit simpler, because they don't require quite as many points and relationships as the abacus did. So, for example, if I select one of the volutes here, and I'm going to do the large volute, and edit the family, then what you're going to see is it's got a lot of dimensions and it looks very busy and very complex, but if we go to the Front view, it's actually pretty simple.
So the first thing I want to do is tab in here and get the 3D form right there and I'm going to come down to the Temporary Hide and I'm going to hide that element. And then I'll do it again there and get the solid join geometry and hide that element as well. And that leaves me with two sets of reference lines. So this set of reference lines goes around and it's all squared off. And you can see that that directly corresponds to the various dimensions that we've applied here.
So I've got Z1, which gives me this location right there. And I've got Z2, which gives me this location right here. And those are both measured from this reference plane. That reference plane is measured off from this height parameter here up from the level. The width this way, between here and here, is set by some parameters labeled X, and you might be able to see those better in a plan view. So there's X2, which is the overall width.
X1, which measures from the center line here. And you've got similar stuff going on here. Now, this little triangle here actually creates a void form, because you may remember that in the main overall family, let's just switch over to it for a moment. That these two come together at an angle. So what that little triangle does is that's a void that cuts out the piece where they would merge together. Because remember, this is one family and this is another family, so instead of trying to join those two families together, instead I thought it would be easier to just do a void there to kind of cut away the part that we don't need.
Now you can try using join geometry and two families, and it probably would work, but in this case I thought the void was a little bit better idea. So I'm going to go back to the big volute here in the front view. The only place I'm using points this time is for these two curves. So this curve right here and this curve right here. Now, these curves are somewhat arbitrary. This one, I just said let's start a point up here, let's end it here, they're both along this reference plane. And then let's take this point and just put it at the middle.
So honestly, that one doesn't require any parameters at all. Notice that that's not linked up, because .5 is always .5. So no matter how long this reference line gets right here, this point will always be in the middle. And as a consequence, this curve will always pass through that point. Now to create a curve that goes through points, you go to this tool right here, Start-End-Radius-Arc, and you turn on 3D Snapping. And then I can click a point here, and another point here, and my third point out here somewhere.
Now this one is somewhat random. But if I can control where this point goes parametrically, see what happens to my curve? Or control this point parametrically. Right, you see what's happening to my curve? Or this point, right, this one actually snapped to the midpoint. So it went right to .5. So if you go in and you establish the locations of those three points, then that's all you need to do. The curve will take care of itself. So the curve will always be a part of a circle, and it will always pass through those three points.
So that's exactly what I did for this curve, and for this curve. Now, this one is more like this one. So let me delete this, I don't really need that. And I needed to establish the location of this point. Now, honestly I just made it up. I just came in and did a dimension, so let me delete that. And I'll add it again. So I did a dimension from the reference plane here directly to the point. And then I assigned that to a parameter.
I just call that parameter X6. It just happens to be the next X in line. So when I'm doing these sort of generic offsets, I just call them X1, Y1, X2, Y2, X3, Y3. I don't really get too hung up on those names. Now, the only bad thing about that is is you might not remember which one was one, and which one was two, which one is three. But when you go to a view, it's pretty self-explanatory. So you know, I've got a height, which is descriptive. And then, measuring down from the height, I'm doing Z1 and Z2. And likewise in Plan.
You know, I've got an overall X, which is the overall width. And then measuring off of that, I've got X5, and X4, and X3. And you can see they're all offsetting back to the original X. So that's just the way that I like to do it. If you can come up with a descriptive name for each of these parameters, then by all means. Descriptive names are always nicer, but sometimes it's a little bit easier to just do this. Now, a relatively new feature in Revit, and I did not take advantage of it in this particular family but I want to point it out to you, is that you can actually select these parameters.
So like this one here is really my overall width, right? So I could select this, and of course I could come down here and I could rename it to Overall Width. But what you can also do is just edit the Tooltip and you could say as much as you want there, up to 256 characters. And when I click OK, if I hover over this, it says the name of the parameter's X, but then in that little tooltip it tells me that's the overall width of the family. So if you want to give folks using the family a little bit more description of what each of the Xs and Ys means, then you can go ahead and take advantage of that Edit Tooltip feature right there.
And I do recommend that you do that. Now, it is a little bit more work. And I know that sometimes we can get busy and there's a lot going on. You could see how many parameters there is here, so we might be inclined to skip that step. But I do think it's a good step to do. So try not to skip it if you can at all help it. And then when we were done here, if I just go back to 3D, this form, let me just go ahead and remove it. Form Element is what I'm looking for on my status bar. And I delete it. If I select this chain of reference lines right here, and add to that this one, this one, this one and the guy at the bottom, right there.
Now, when I click Create Form, it will suggest either a plane or a solid. I want the solid, and then of course you can adjust the depth of that. Now the right way to adjust the depth of that is to look at it in Plan here. And I had that one snapping to that reference plane right there, and you can lock that and then the same thing out here, I had that one coming out to this depth here. So if I go to a line, and then that's its form surface. I'm going to lock that.
And let's just make sure this one's locked as well. So now when we look at it in 3D, that gives me the straight extrusion. But to carve that little wedge away, you just do Cut Geometry. So I do Cut. Take this, and cut it with that. And now I've cut that little wedge away. Now, I had to figure out what that angle is. The way that I did that was back here in the main family, I loaded it in and then in a Plan view, I just simply fiddled around with the rotation of this item until I was satisfied with it.
It inserts right here at that little point. And then I just rotated it, and then when I saw the way it rotated, I just drew a little line on top there and I just measured the angle of that line. And that told me what angle to draw the triangle at. So there was a little bit of back and forth trial and error that I had to do, so when you're working on a complex family like this, you're going to do a lot of loading and going back to the other family. Load it, check it out, go back to the other family, make adjustments, and so on. But you can see that once you've figured that angle out, then it's just a matter of mirroring it and copying it around to the other locations in here.
I mean, I have eight of these total so I didn't place each one manually. I placed one, and then I just did a bunch of mirrors. So that kind of gives you the overview of how this whole thing comes together. And if you explore any one of these nested families, you're going to find that they're all structured the same way. They're all very similar, there's a cage of reference lines. That cage of reference lines has parameters holding it together so that it will flex. And then it's just simple extrusions. And then all those parts are loaded in here.
And if I flex this, the entire family will flex because they're all using those parameters. So again, the critical aspect of that if you recall was to make sure you select each of these families when you bring them in and link up that base diameter parameter. That base diameter parameter drives the whole thing. So you want to make sure that the top level family is always pushing the base diameter through to the nested families and as it does, it will make sure the everything flexes properly.
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