In the very first Connecticut houses, architectural detail was minimalistic and strictly utilitarian. But even the earliest colonists wanted their homes to look good, so in time, both interior and exterior detailing began to take hold. Much of this elaboration incorporated both Classical and Jacobean forms. And even prior to the middle of the eighteenth century, arriving English carpenters had begun infusing colonial architecture with the prevailing nuances of Georgian England, and the teachings of Christopher Wren.
Colonial carpenters sometimes added their own unique flourishes, and often you’ll find variations of the same basic architectural theme in different locations. For example, the fireplace paneling in the parlor chamber of the Rev. Richard Mansfield House (c. 1700), about fifteen miles away in Ansonia, Connecticut, includes elements nearly identical to those detailing the entrance of the Curtis home:
In recent times, I’ve become obsessed with colonial architectural detail, and its evolution within the Connecticut and New Haven colonies, and their surrounding regions. In particular, I’m determined to capture as many surviving examples as possible, both in photographs, as well as in three dimensional models drawn using Trimble SketchUp. I’d also like to establish an online archive of architectural models unique to our region.
To this end, I’ve selected another example from the Mansfield House for an initial survey project — the fireplace paneling of the hall chamber, which is rather nicely executed, but also sufficiently straight-forward to make for a reasonable first attempt:
As often was the case in early Connecticut homes, the fireplace paneling here is integrated with the chimney girt and rear post, stylistically “supporting” the girt as a simple cornice or entablature, via a bed molding. This particular fireplace paneling sports a number of interesting architectural features, including this rather elaborately built-up mantel shelf:
Also of interest is the heavy bolection (sometimes called Italian) molding surrounding the fireplace opening, while the panels themselves are beveled, and rabbeted into beaded rails and stiles:
So, to start off as simply as possible, I decided to initially model the bed molding beneath the chimney girt (excluding, just for now, the small cove supporting it), which is of classical cyma recta contour, and includes a mitered return at the end opposite the post:
The other end of the molding terminates flat against the rear post’s casing:
I collected contours from three different locations along the bed molding (all were slightly different), and standardized on what I’d hoped was a reasonable interpretation, on my part, of what the original craftsman had intended:
I did so using a standard contour gauge:
And transferred them as best I could to my engineering notebook. I also measured and recorded all of the lineal dimensions of the molding as accurately as I could (a pair of very long dividers comes in handy when measuring irregularly shaped or obstructed features):
Once I felt reasonably confident in my measurements, I set about building an initial SketchUp model of the molding, by first drawing the rectilinear segments of the molding contour in two dimensions, and adding guidelines corresponding to the vertical graph lines of my notebook:
Next, I added horizontal guidelines corresponding to the points where my captured cyma recta curve intersected with the vertical lines. I then used the SketchUp arc drawing tool to fit as smooth a curve as possible between these intersections:
The final, two-dimensional representation of the contour looked like this:
Using SketchUp’s pull tool, I then extruded the two-dimensional contour upward along the third dimension:
Then, I “flipped over” and rotated this three dimensional shape so as to properly align it with the standard axes defined by SketchUp. Doing this ensures that modeled components are correctly oriented when combined together to build more complex models. I also lengthened it a bit. Here’s what the resulting molding section looked like:
Now that a basic molding section had been created, my next big step was to figure out how to miter either end. Unlike real molding, I couldn’t take a double-bevel compound miter saw and simply cut it — that would’ve be too easy! Instead, I had to figure out how to “cut” a 45 degree miter in SketchUp. SketchUp is a bit rigorous about what you can and can’t do when altering irregular shapes. Admittedly, I had to try this a few times before I finally got it right. What follows are screen shots of the steps I performed, in the event this is useful to others attempting to do the same thing (if you’re not, feel free to skip over the impending tedium).
The first step was to rotate the molding section so as to view its back side, and draw a 45 degree guideline across its top:
Then, I “scored” a vertical line down the backside of the molding section, beginning at the miter line:
Next, I selected the near vertical edge, and, making sure that nothing else in the model was also selected, attached the SketchUp move tool to the top corner of that vertical edge, and “swung” this vertical edge over to meet the miter line. The end result looked like this:
The resulting white appendage seen above is the projection of the other side of the contour into the three-dimensional solid, and it now needed to be carefully removed by “intersecting” it with the remaining solid, and then “subtracting” it away. To accomplish this, I first drew a solid line along the bottom edge of the white geometry:
Then, using ctrl-left-click, successively selected each of the curved contour sections (remember those vertical lines I needed to hide earlier, after I’d first pulled the two-dimensional contour upwards into the third dimension?). In the screen capture shown below, the top two or three contour sections have been selected (indicated by the slightly greyed-out areas):
Next, I used SketchUp’s intersect faces with model operation to effectively divide this section from the main model. Once this operation is actually performed, the curved line where the contour meets the mitered wall goes from transparent to solid:
Now that the model had effectively been divided, the unwanted portion needed to be deleted. To do this, I rotated the section back the other way, selected the main edges defining the separated contour, and then performed an erase operation:
The end result of this was a cyma recta section with a 45 degree mitered end:
I then repeated the same steps in creating another molding section, but one with a 45 degree miter on the opposite end:
As a result, I now had both “left-hand” and “right-hand” mitered sections, saved as SketchUp components that I could readily import into a model and join together to form corners:
Finally, by extending the non-mitered end of a “left-hand” section out to full length (in this case, 89-3/4″), and appropriately shortening a “right-hand” section to model the return, and then joining them together, I created an accurate model of the bed molding beneath the chimney girt in the Mansfield House’s hall chamber:
This second view of the same model reveals more clearly how the return had been cut from a separate piece of wood, and simply joined to the mitered end of the main piece:
There’s no doubt that modeling historic architectural detail in this manner is a lot of effort. But it’s time worth spent for anyone serious about capturing this information and making it readily accessible to others. The educational advantages of three-dimensional, digital models are significant: one can readily view, explore, rotate, and deconstruct such models to learn more about them. Also, if arbitrary two-dimensional plans or sections are desired, they can always be produced directly from the same three-dimensional model, without the need to create additional diagrams.
Furthermore, once a library of standard components has been established, new models can readily be created by piecing existing components together, and creating customized versions of those components wherever necessary. Models formulated using Trimble SketchUp can easily be published on the Internet via the Trimble 3D Warehouse. For example, both the left and right cyma recta sections I’ve created here may readily be downloaded from my own Trimble 3D Warehouse page. They can then be viewed using either Trimble SketchUp or Trimble SketchUp Viewer.
Finally, yet another advantage to publishing archives of models of historic artifacts online is that well-established SEO techniques can be leveraged to ensure that these model catalogs are found by those searching for them, while social media can likewise be used to publicize the existence of these archives to their intended audiences and communities.
This modeling exercise of mine was (very gently) criticized, recently, via Twitter, on the claim that there was no obvious, practical need for three-dimensional models of historic architectural millwork. While I don’t agree with that claim, I do understand the basis for it.
If I were creating a collection of SketchUp components representing well-known classical forms, or even standard millwork, then I’d happily concede that my critic had a point, as these forms are widely understood, and a great many examples of them have already been published in the SketchUp 3D Warehouse. But what I’m doing here is capturing the architectural details of specific historic buildings, and as such, I consider each modeled element to be fundamentally unique, even if it expresses some well-known shape.
For example, there’s nothing particularly profound (in a more general sense) about the model of the bed molding that I’d developed and illustrated through out the course of this article. But this small component will soon become part of a larger model of the entire paneled composition, which itself is quite unique, and of considerable historical significance. In that sense, even a trivial piece of molding needs to be accurately represented here. So I’m not inclined to search the 3D Warehouse for close equivalents, but rather model these pieces myself, and directly from my own measurements of their real world prototypes.
I should also point out that the models I’m constructing and publishing are primarily of regional historic interest. Some one researching the habits of early Connecticut carpenters might find them invaluable; but general architectural historians, perhaps somewhat less so (or maybe not). These are points I didn’t make completely clear earlier, especially in the above Summary, which seems to suggest more general intentions.
And finally, a secondary objective of the article itself is simply to share my own experiences using SketchUp with others who are undertaking similar efforts.
Here’s a photo of another cyma recta bed molding from the Mansfield House, this one from the hall fireplace. A small lower section missing from the return reveals that the molding is shaped from an angled board, as initially suggested in a comment posted by Jane Radocchia, and subsequently discussed by Sebastian Eggert:
This molding is of the same contour and dimensions as its counter part from the hall chamber, and I have no reason to believe them to have been constructed differently. So as soon as I’ve had a chance to measure the section, I’ll revise my earlier model to reflect this shape. And that same model will be used to represent either bed molding. So much thanks to both Jane and Sebastian for encouraging me to consider this.
Also of interest is the contour shown below, which was recorded by famed New Haven, Connecticut restoration architect and historian J. Frederick Kelly, on p. 192 of his “Early Domestic Architecture of Connecticut” (published in 1924). Kelly cited it as an example of a non-Classical contour that was indigenous to Connecticut, and often found in later period (Revolutionary to Greek Rival) compositions through out the state. So I’ll be keeping an eye out for this one in my travels, as well.