Architectural Tree Art: A Handrail Project
October 29, 2016
INTRODUCTORY REMARKS …
After two years of not adding a post to this blog, I felt a need to return to it, to document the tree art railing project. But I also had a sense of digital intimidation and resulting stress. I also felt an uneasy concern about justifying all the time and energy it takes both to prepare and to publish so many photos and so much text. Then I found myself questioning the worth of doing it.
But, I appreciate the opportunity to practice my writing skills, in preparation for the possibility of someday completing a book-length manuscript about the remarkably contorted lodgepole pines, and my making of tree art.
(I want to add the fact that I had already completed a version of this post–many photos and 500 well-written words–a few days ago I was pleased with the process until, when I pushed the “publish” button, the post vanished into cyberspace, and no amount of technical support could find it.)
Finally, following some general comments on design, materials, and workmanship, this post features a lengthy series of annotated photos.
The handrail project is an example of what I call “architectural tree art,” as distinguished from “tree art furniture and sculpture.” I first made that distinction out of an appreciation of the Old Faithful Inn’s architectural use of contorted lodgepoles. (I have published an essay on my admiration for the inn’s architect, Robert Reamer, and the carpenters/tree artists who implemented his designs.)
Our house in Virginia City, Montana, has a wraparound greenhouse/glassed-in porch, with an interior deck and staircases, in need of handrails for over ten years. Since it had been a couple of years since I made any tree art, I decided to design handrails both out of necessity and an urge to add a feature of architectural tree art.
As some of the accompanying photos show, the unfinished greenhouse is also serving as a storage space for a variety of contorted lodgepole pine tree trunks. From them, I selected certain “motifs”– “swan neck”, “loop-around”, “spiral “, “forked 4”–for use as posts and lower rails. All of these tree trunk shapes are naturally grown as each tree has outgrown adversity of some sort, and regained its original uprightness, straightness, and center of gravity!
For the top rails I used salvaged pieces of the original 1871 log house wood chinking, which had been removed in 2004 when the lap siding was taken off to reveal the log structure. I liked the idea of combining the historic lumber with the contorted trees.
As with the making of tree art furniture and sculpture, an essential challenge comes with choosing types of joinery that accomplish both structural strength and an overall, flowing sculptural unity.
I used the following five types of joinery: cylindrical mortise and tenon; post and socket; mate-cut butt joint; scribed notch; and half-lap. Each of the joints were reinforced with log screws.
Some of the photos show matching pairs of “position-key marks” on each of the joint’s components. These marks are necessary to guide the repositioning of pieces that have been separated during fitting. (See photo below.)
A special note of thanks to my quasi-apprentice, Drew Xanthopoulos, for serving as a human railing clamp, and a supple ratchet operator inserting the long lag screws.
The project will remain unfinished for awhile. At some point I will complete the cosmetic work, including filling, shaping, sanding, and staining.
This view shows the entire deck and handrails, as approached from the front, inside of the greenhouse. The log house’s exterior door opens to the deck’s upper landing, and the greenhouse exit door is on the left below the deck.
The bottom staircase edge is off-set from the main deck surface, presenting a safety concern. Selecting the three posts and two handrails to make a curved and descending handrail was a structural, design, and joinery challenge.
This view is from the back (north) end of the greenhouse, showing the repeated “motifs” of the posts (swan neck) and of the lower rails (loop around). The stacks of contorted lodgepole pine tree trunks in the background provided the inventory to select the handrail components.
The deck framing and surface are salvaged redwood. The top handrail is made of two pieces of lumber that served as original wood chinking between the house logs (built in 1871.) All of the posts appear to be sitting on top of the deck (which they are), but they also are penetrating through the deck surface and are secured underneath with 1/2″ x 7″ lag screws to the deck’s substructure. (See photo below).
This short handrail section makes it easier and safer to descend from the upper landing. I like its freestanding simplicity and strength. The bottom of the “forked 4” post extends down six inches into a cylindrical socket drilled into a pair of staircase joists–a variation of the cylindrical mortise and tenon joinery.
The bottom of each deck perimeter post was shaped into a cylindrical tenon–three inches in diameter, one and one-half inches long–with a square (not tapered) tenon shoulder. The shoulder sits flat on the deck surface, so that the outside circumference of the post also covers the three inch mortise (i.e., the hole or socket). The above photo shows the joists and blocking underneath the deck, and how the post is secured tightly to a framing block by a seven inch lag screw that penetrates deeply into the bottom end grain of the post (also seen above the deck in this photo.)
After cross-cutting the posts to a uniform height, and plumbing and aligning them in a row, I laid the flat side of the top rail on the row of post tops and scribed an outline circumscribing the circumference of each top onto the underside of the top rail. Then, using a router, I created a half inch deep socket to receive each post top. When the top rail was in place, including a half lap joint over one of the posts to connect the two pieces, I secured the rail with log screws.
The top rail length required that I use two pieces of the wood chinking, so I created this crude but strong half-lap joint over the post. The bottom half piece also has a half inch deep socket to accept the post top. The joint will be further shaped and cleaned up in the finishing process.
In this photo and the next, are examples of a “mate-cut butt joint.” This joint is named for the fact that, after many preliminary saw cuts, the saw blade actually cuts both surfaces of the joint –the end of the rail and the side of the post– with each of many strokes. Note the pair of black lines at the top of the joint. As noted above, I call them “position match marks.” The mate-cut joint will only realign correctly one way.
As part of the finishing process, the joint will be “sculpted” to flow together.
In Conclusion …
In the process of creating this post, I have realized that the essential values of doing it are intrinsic. And that is true of most of my poetry (“makings” that also include creative writing and playing guitar and harmonica). Having said that, I want to add a note of thanks to anyone (in an invisible audience) who might find something here of value.
Thank you …!