Interview

Emily Shaw is an accomplished guitarist and luthier based in Ottawa Ontario.  We met at the Guitar Hamilton summer festival a few years ago and struck up a conversation when she saw the photo of my reproduction of the five course guitar made by Stradivari known as "the Rawlins". She'd also completed her own copy!

Recently Emily has undertaken a wonderful series of interviews with fellow luthiers on her blog and I felt very honored when she asked if I'd participate. Check it out:

https://guitarsbyemily.wordpress.com/2018/06/14/shop-talk-a-conversation-with-ted-woodford/ 

Carving a Lute Rose

I made a short video describing some of the processes used in carving the soundhole ornament on Renaissance and Baroque lutes.

Making a Pyramid Guitar Bridge

A short video describing my process for making the pyramid-style guitar bridge used by C.F. Martin and other early American guitar makers.

Making Mosaic Rosettes

A short video describing my procedure for making decorative tiles for rosette inlays.

Interiors

Some recent works-in-progress.  Flamenco with subalpine fir top / Alaskan yellow cedar body on the left, Classical with Western Red Cedar top / Indian Rosewood body on the right.  The five-strut arrangement with diagonal "treble" bar relates to some work I did from a Miguel Rodriguez plantilla some years back. I really liked the sober character it produced in the basses.

Soundboard

A flamenco top in progress.  It's a five-bar pattern with an angled treble brace and no "cut off" bars near the tail block. I found that leaving these off adds a certain raucous quality to the overtones that seems in keeping with the spirit of flamenco. The barring above the sound hole is quite robust. I run the transverse bars at full height right across, without scalloping.

Thicknesses start at about 2.4 mm in the vicinity of the bridge, thinning to about 2.1 at the periphery.

One thing I've learned from looking at older instruments is to leave a little space between the end of the bars and side. The box of a guitar is apt to shrink a little bit over time. The top and back can contract, but the transverse bars don't shrink much at all, oriented longitudinally as they are. If they butt right up against the sides they inhibit the contraction and can cause cracking.   I store my materials carefully and build in a controlled environment but one never knows what humidity conditions an instrument might find itself subjected to during its lifetime.

Some Rosettes.

I recently spent some time making and installing rosettes, and I've updated my methods a little with some high-tech gadgetry since the last time I outlined my procedure.  Here's a little compass cutter I use to outline the channel.  This produces a much cleaner margin than simply plowing through with the router.  The scalpel blade is compressed by a block simply screwed to the beam. It rides right on the surface and cuts to a depth of 2mm.  There is a 1/4" (6mm) pin which protrudes through the soundboard and into a bushing housed in a workboard beneath. This makes adjustments really precise.  A bolt ties the beam to the platform with a plastic speed-knob. Simple, and it works like a charm.

A similar setup serves to adjust my laminate trimmer.  You can see that I set the cut about a millimeter away from the knife line. Depending on grain direction, in some places the residual material gets blown off by the force of the router. The stuff that remains is easy to pare away with a chisel.

I've followed Eugene Clark's method for rosette construction for some time, including the use of waxed spacer lines to take the place of border and tile elements.  That makes for a lot of work -cutting an extra 20 veneer strips, waxing each one, etc., and they're not reusable!  I thought I'd try some of this UHMW (Ultra High Molecular Weight) plastic sold through various woodworking suppliers as jig-making material for table saw miter tracks.  It's durable and glue does not stick to it at all.  I ripped pairs on the band saw in increments of 2, 2.5, and 3mm, color coding them and trimming them to length to fit into the rosette channel.

Border material is cut on an angle in a tiny little miter box sized to fit my fine backsaw.

The plastic strips pop right out, and the tiny little pieces are glued in the resultant channel.

I've decided to keep things simple and bold.  I've been looking at a lot of rosettes recently, and coming to some conclusions.  I think I'm most attracted to the early Spanish designs which rely more on geometric patterns than pictorial representation. In the one on the left, in fir, I made the border quite large.  It seems to me that there are two trends in modern classical rosettes - one being the use of spalted or other highly figured woods as a focal point, the other being extremely detailed mosaics.  To my eye, they seem out of proportion to the instrument as a whole and get completely lost unless you happen to be right up next to them. A position neither the player or the audience is likely to find themselves in.  Though I'm fond of spalted wood, I'm not eager to jump on that bandwagon.

There's a quality of mechanized precision to most of the commercially available rosettes that I think is at odds with a handmade aesthetic.  I like the little irregularities this process imparts. They're not jarring, but they do add a floating quality, and visual movement.  It takes quite a while to make one of these things, but there's a kind of novelty to the process.  It's contemplative. In the example on the right in red cedar, I decreased the size of the border and flip-flopped the border tile (made from the exact same veneer lamination), and it creates a significant contrast. I thought the larger field of pearwood might echo the color of the cedar in a pleasant way.

(These photos were taken after scraping the surface level, but prior to sanding or the addition of finish.)

Closing the Box

Here we have the finished interior. In this instrument I've used "tenelones", or individual glue blocks, to secure the top to the sides. This is a technique borrowed from traditional Spanish practice which works well when a "solera" or dished workboard is used. In my experience there is also a palpable sonic difference in guitars constructed this way vs. the use of continuous kerfed lining. It's not so much that the voice is different, but there seems to be an immediacy to the sound.

In any case, I've used the kerfed lining on the back. This is Spanish cedar, by the way. It costs a little more, but it imparts the most wonderful aroma when one holds one's nose up to the soundhole in search of a lost plectrum.

I've doubled up the tentelones in the lower bout where I intend to install a wide chamfer for forearm comfort.

I'm trying something different in this guitar, using douglas fir for the top and bottom blocks. I got the idea from watching Robert Bennedetto's archtop construction video. I was surprised to find that he often uses spruce for his blocks. Since I had appropriately sized offcuts, I decided to give them a go. For my steel stringed instruments I've settled on a bolt-on neck attachment system. I've tried dovetails, straight tenons, and various bolt configurations. I like to make things easy for future repairs.

There are a number of different ways to close up the box. I often use rope. In some cases I've used go-bars. Today I had my box of spool clamps handy.

Spool clamps are a holdover from violin construction. They're a low-tech solution. They're also indispensable for repair work if one is trying to fix cracks in the sides, or if you've removed a top or back for interior repairs. At the top of the upper bout you can see a brightly coloured smear. A hairline fracture occurred during bending, which has been stabilized with thin superglue.

I suppose the alternative would be small quick-grip trigger clamps, but I'd need $1000 worth. I made these up from theaded rod and closet pole for less than a dollar apiece. They provide just the right pressure. A slightly oversize through-hole means they can pivot to accommodate the back arching. Cork lined surfaces prevent marring.

Front view. This illustrates a subtle little thing I've learned through experience. I've left the soundhole rough, and won't complete it until just before the finishing process. This ensures it will be clean, and any little dings or divots incurred via clamping the fingerboard in place or fretting will be sanded away.

Making an inlayed rosette, Part 1

I've started work on a new instrument this week, a midsized steel string. I intend to follow the construction closely with frequent blog updates!

Here I'll describe my process for making the traditional Spanish-style mosaic inlay used to decorate the soundhole perimeter on classic style guitars. I've scaled the size down a little to be more in keeping with the steel string aesthetic.

I credit this entire process to master luthier Eugene Clark, who's method was detailed wonderfully in the Journal of American Luthiers, issues 71 and 73.



My rosettes are constructed from strips of veneer (0.5 mm/.025" thick). Some of these I buy in sheets ready dyed, others I color myself using aniline stains cooked in a big pot on the stove, not unlike spaghetti, but even more al dente'.

I've devised some interesting jigs to cut the strips. In the end I came to the conclusion that by just making little pencil marks and going at it with a wooden straightedge and sharp knife, my eye quickly becomes adjusted to gauging the size. It's much quicker and accurate enough. They end up about 2mm wide, a convenient size to work with. Eventually they'll be scraped square in cross section.


Traditional steel string instruments often have designs made up of concentric lines- a quick and easily accomplished solution for the factory. Early Spanish luthiers often employed geometric or floral patterns. Eugene Clark associates the design process with weaving and textile arts. To me, it feels more akin to the Italian art of Millefiori glass.

The pattern options are boundless! As individual craftspeople we have the opportunity to be a little more personal with the motif. I'm using this little character here, a skull figure that in this format has a definite old-school Space Invaders aspect. (Yes, I know there's no nasal hole! Don't ask me why - that's just the way it is!)

I plotted the design out on graph paper and transcribed the squares of color into a sequence to assemble the lines into individual rows.


Having a big sink nearby is important. It's a messy business. The top of the washing machine becomes a ready made workbench! I'll be using yellow carpenter's glue as an adhesive. The laminate workboard has a piece of hardboard screwed down to make a straight fence to press against. It's hard to see, but the edge has been covered with clear packing tape to provide waterproofing.

I'm not stingy with the glue. It's important to get every strip thoroughly saturated. The glue has been thinned with a small quantity of water to extend the working time. I cover five or six strips at once and line them up. They are then squeezed lightly between thumb and fingers and excess glue wiped off before adding more lines to complete one row of the pattern.

A couple of thin Plexiglas sheets provide a light, even pressure to hold the now assembled row straight against the fence. The surface of the workboard and fence has been slightly dampened to prevent the row from sticking too firmly, but also to provide a little surface tension to hold the plexiglas down flat on the board. The five minute interval required will allow the glue to seize up before I run a pallette knife around the row to free it. The next row goes in, and the previous row gets set aside to dry.

The rows have now been readied. These are about 12", (300mm) long. This length is easy to work with and cuts down on the incidence of breakage during the thicknessing process.

Rough thicknessing proceeds with a block plane. I hold the rear end of the row in my hand - there's no safe means of butting the row against a stop block as it's too thin and would bend or break.

Planing yields a big fuzzy ball of gore.

This is an old #90 Stanley shoulder plane in bullnose con-figuration clamped to a maple block at close to 90 degrees. The rows are slipped between the blade and fence at a point about 1/3rd their length and pulled (carefully) toward me. I then reverse the strip to scrape the other end. As I started with veneer 0.025" thick, that should be the final thickness of these strips to ensure the ends will as tiny squares in the finished product. Work progresses by advancing the blade in very small increments, flipping and rotating occasionally to ensure even stock removal, and eventually things get done. It takes some time, but it's a good opportunity to reacquaint ones'self with an old album, in this case it was Muddy Waters' "More real Folk Blues".