Pierced panels: Gothic tracery in frame-and-panel construction.

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My friend Holland (Alasdair MacRoibert in the Society for Creative Anachronism (SCA)) is an accomplished professional woodworker.  So I (and others) had been encouraging him for some time to enter pieces in competition and to seek other opportunities for showcasing his work.  When a Request For Proposals for new thrones for the SCA Kingdom of An Tir was announced I pestered him mercilessly until he submitted a bid.  He not only won the bid but he also got his revenge: he put my name in as his assistant.  Little did he know that I would thoroughly enjoy this project.

His first assignment to me was to help design, and then fully execute, carved panels to sit in frames making up the “box” of a box-seat high-backed arm chair.

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An example of a 15th century box-seat high-backed arm chair.

We toyed with quatrefoils and cruciforms for a while, but ultimately he accepted my suggestion of trefoils.  I have been using trefoils as corbels and on through-tenons for several years now, starting with a break-down bench made for my friend Aline Kevorkian (Mistress Gorandookht Mamigonian).  I enjoy their sense of harmony.  Historically, trefoils represent the mystery of the Trinity and the spirit-mind-body nexus.  Harmony, mystery, and metaphysics; seems to me a worthy association for the thrones of An Tir.

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Layout template designed by Holland Cooley, executed by author

Using a plan drafted by Holland, I started by creating a template on medium-density fiberboard (MDF).  I did this by firmly taping the draft onto the MDF, slicing out the negative spaces with an X-acto knife, and then tracing the design onto the MDF with a mechanical pencil.  I then drilled out starter holes in each negative space using a drill bit with a diameter larger than the width of my jigsaw blades.  Slipping the jigsaw into each starter hole, I was then able to quickly waste out the negative spaces.  The narrow corners were cleaned up using the X-acto knife.

Reading back what I wrote above, it strikes me that I seemed to have used thoroughly modern tools and techniques.  But did I?  Evidence abounds of the medieval use of templates in woodworking and masonry.  Alexander Holton asserts that the Mason’s Loft in York Minster was largely used for layout, execution, organization, and storage of the countless templates used during the construction of the great cathedral.  Many of the racks used to store the templates are still present.  Whereas I used tracing paper, the artisans of York used a plaster stenciling floor.  Whereas I used a drill-press and a jigsaw, medieval pattern-makers likely used bit-and-brace drills and key-hole saws.  In other words, my materials and tools were merely the modern descendants of those used in the 13th century.

Using the template, it was a simple effort to trace the layout onto the four panels of hard maple Holland had already rabbeted for me.

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Once the four panels were prepared, I moved back to the drill-press.  Using a 2 1/4″ Forstner bit, I bored out each of the trefoils.  As Forstner bits do not have a centering point (like spade bits do) I used a small, precise right-angle to line up the edges of the bit with the layout lines and then clamped the panel down hard against the press table to ensure that the drill’s torque would not shift the panel.

After the trefoils were wasted out, I went back to the jigsaw and a frame saw to waste the triangles, arcs, and “fiddly bits”.

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Four pierced panels, waiting to be beveled

Up until this point, Holland’s plan had been to glue matching hard maple to the backs of the panels.  This would add strength, but they would no longer be “pierced”.  After some discussion about the strength of the design and the thickness (nominally 1″) of the wood we decided to forego the backing and allow the panels to remain pierced, as we think they are more aesthetically pleasing to the eye.  We also agreed that they should be beveled at a 45° angle at a 1/4″ depth.

I have beveled plenty of straight edges.  This is a simple affair when using a plane.  Beveling complex curves, however, is something I had never tried before.  So I took a few days to sharpen several of my chisels and gouges, re-read parts of Hasluck’s Manual of Traditional Woodcarving, and found an extant piece to use as reference.

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Fragment of rood screen, oak, dated 14th century

I began by creating a new template for the bevels.  Using the original template, I traced out a new one, then drafted lines 1/4″ outside of the negative spaces.  Using the same techniques as before, I then wasted out this new template and used it to transfer the bevel depth lines onto the panels.

Now began the pains-taking process of carving down the bevel lines.  Initially I tried using a jigsaw set at a 45° angle.  The areas to be carved, however, are so close to one another that the end of the blade was at risk of damaging proximal areas.  I completed the rest of the work solely using hand tools.  After trying out several gouges, ultimately I settled upon using just two chisels (1/4″ and 1″) and a wooden mallet.

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Pre-severing a line in the ‘valley’ where two bevels merge

On the first two panels, I pre-severed the fibers at all of the bevel lines.  I did this to prevent the wood from splitting ahead of the chisel past the intended area.  Pre-severing all of the lines took about an hour per panel; for the latter two panels I ended up only pre-severing at the ‘valleys’ where bevels meet and at the end of straight bevels running with the grain.

Among the trickier aspects of this project is the rapidly changing direction of the grain relative to the curves.  An inside curve of a trefoil, for instance, would typically have four distinct areas of grain direction.  Transitioning from one grain direction to another requires repositioning of the tool, the panel, and the carver’s stance.  To not reposition would result in tear-out (chunks of wood be pulled out of the piece) if carving against the grain, or splitting if the chisel gets caught running with the grain.

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For the inside curves I turned the chisel over and pared bevel-down.  Now I realize that I’ve just used the word ‘bevel’ in regards not to the carving but to the tool.  A bevel in woodworking is a slope from the vertical or horizontal.  In the images above you can see the bevel (slope) being created from a horizontal plane to a vertical surface.  The word can be a verb too: I am beveling a bevel.  It also applies to the slope running from the back of the chisel to the sole, which creates the cutting edge of the chisel.  Usually in woodworking, a chisel is held with the sole against the wood being pared.  The sole acts as as a plane and allows the carver to (barring accidents) slice in a straight line.  But for tight inside curves the carver needs to slice not in a line but in a tangent around the arc.  By flipping the chisel over the carver can rest the chisel just on the point where the bevel meets the back of the blade.  This point can then act as a fulcrum in paring and slicing one’s way around the curve.

The complexity of the various curves and straight lines interplaying with the changing relative direction of the grain meant that carving each panel was a detailed process.  Each panel took between three and four hours to carve.  The hard maple was beautiful to work with, but wore the edges off my chisels pretty fast; I had to resharpen them twice during the project.

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After all four panels were carved, I cleaned up the more obvious of the tool marks using a four-in-hand file and a card scraper.

 

Addendum:

After the panels were delivered, Holland asked me to help on the carvings for the backs of the thrones as well.  These back panels were already wasted when I got them, so all I was asked to do was the carving of the bevels.  Unlike the panels shown above, the back panels will be “backed” with another, thinner, panel so that they will not remain “pierced”.  This decision was made to avoid the audience from being able to see retinue moving around behind the thrones.

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Photo by Holland Cooley

I used the same methods and tools as with the trefoils.  A new nuance was how Holland wanted the four layers of gothic arches to appear to interweave.  This required some careful attention to the paring wherever the vertical of any arch intersected the arc of another arch.

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This was a great project for me and I really honed my carving skills.  I greatly appreciate Holland for allowing me to help with the overall thrones project.

Bibliography

Holton, Alexander “The Working Space of the Medieval Master Mason: the Tracing Houses of York Minster and Wells Cathedral” monograph

Hasluck, Paul “The Manual of Traditional Carving”pub. 1911, Cassell & Company, London