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Pearly Shells and Nichols

Pearly Shells and Nichols

by David Nichols

from his 1984 GAL Convention lecture

Originally published in American Lutherie #1, 1985 and Big Red Book of American Lutherie, Volume One, 2000



My shop recently did two guitars for the Martin Company which are elaborate enough that they encompass basically all the different techniques used in pearl inlay. We inlaid the tortoise shell pickguards, the rosewood headstocks, ebony fingerboards, and all edgebinding. I photographed many steps in this process, and we can look at these as examples.

Here’s a picture of where I’m going to cut the pearl and do the inlay work (Photo 1). I have taken an extra liberty with our cutting board, drilling a series of holes in the back where I can stand all the little Dremel attachments that I’m going to need. When we cut pearl, it is either filed, or ground with the Dremel to an exacting contour after we saw it. It gives you a much better looking job if you touch up the sawn edges of the pieces before you put them in.

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Questions: Guitar Rib Depth

Questions: Guitar Rib Depth

by R.M. Mottola

Originally published in American Lutherie #85, 2006

 

Mark Korsten of Hastings-on-Hudson, NY asks:

The article concerning how the rib depth of guitars should be adjusted when plates are domed was clearly written and illustrated (AL#84). I truly appreciate the insights offered by author R.M. Mottola. Being a neophyte luthier, however, I have what is probably a naive question. How does changing the depth of the guitar’s ribs modify the manner in which the bindings are fitted to the binding ledge? It’s a fairly easy operation to bend the binding when the plates are flat. However, when the depth of the ribs are varied, doesn’t that introduce another plane to the geometry? Do you simply use more flexible, thinner bindings or stronger binding tape to keep things tightly apposed in the ledge?


R.M. Mottola
responds:

Although the doming of the plates means that the side depth of the ribs must be varied so the ribs and plates can be glued, this type of construction has little effect on binding. The ledges can be routed using a router resting on the plate or inverted in a router table. In either case the doming is so slight that the routing can be done just as if the plates were flat. And although the bindings must be bent vertically to accommodate the varying rib depth, the amount is so small as to be inconsequential. ◆

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End Mill Cutters

End Mill Cutters

by Bruce Scotten

Originally published in Guild of American Luthiers Data Sheet #149, 1980 and Lutherie Tools, 1990

 

The use of routers to cut channels for binding, purfling, and rosettes is quite common. One problem associated with this tool is tearing and chipping caused by the use of standard router bits. A simple solution is to replace router bits with end mill cutters. Their advantages are: the increased number of cuts per revolution (4, 6, or even 8 flutes or edges, compared to 1 or 2 on router bits); plus the right-hand cut, left-hand spiral option which cuts with a downward motion that prevents the hairing and tearing caused by right-hand spiral lifting, and the slapping effect of straight router bits.

End mills are more expensive than Stanley or Sears router bits. Solid carbide, 1/4" shank, 1/4" cutter, right-hand cut, left-hand spiral end mills are about $20. However, decreased down time and improved product performance make end mills a sensible alternative for the serious luthier.

End mills are used more in metal working than wood working. Therefore any machine shop should be able to direct you to a jobber specializing in cutters. Johnson Carbide products in Saginaw, Michigan is a reliable source for end mills if you have difficulty locating them in your area. ◆

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Pre-bending Herringbone Purfling

Pre-bending Herringbone Purfling

by John Calkin

Published online by Guild of American Luthiers, June 2021

 

Herringbone purfling s a lot easier to work with if it is prebent before it is glued onto the guitar. This is best done after wetting it first. I always use a brush to spread glue on guitars. I keep a coffee cup of water handy at all times, along with an acid brush with the bristles properly trimmed back to the stiffness I like. I dip the brush, then hold it stationary as the strip of purfling is pulled across the cup underneath it. Soak the purfling well on both sides. This should take only seconds. Then the strip is pulled through a dry cloth. Soaking it for too long will encourage it to come apart as it is bent. Give the purfling a minute to absorb the water, then tape the butt end into the channel it will be glued in later. Wrap it carefully around the lower bout using a couple pieces of masking tape to hold it tight. More tape, as well as care, will be necessary to make it conform to the waist area. The wrap around the upper bout should be as easy as the lower bout. In the photo, you can see how much tape was used as well as the small fan used to dry the purfling before gluing it in place.

All photos by John Calkin

Herringbone will wrap around a moderate Venetian cutaway but do it gently and by stages. To be safe, the purfling can be wet and then sliced lengthwise on one of the glue joints using a single-edge razor blade.

On a tight Venetian cutaway, the purfling must be sliced. On this tight-waisted jumbo guitar, the purfling was sliced from the top end to below the waist area to help coax this half-herringbone purfling to conform to the shape of the guitar. Sliced purfling doesn't need to be prebent but you might wish to wet it as you reach that portion of the install. Slicing the purfling can go awry and destroy it. Buy extra. ◆

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Brazilian Guitar Makers

Brazilian Guitarmakers

by Roberto Gomes

Originally published in American Lutherie #33, 1993 and Big Red Book of American Lutherie Volume Three, 2004



The guitar has been the main musical instrument in Brazil since it was brought by the Portuguese colonizers centuries ago. In those times, Baroque guitars were the most common string instruments. They had five courses of gut or wire strings. Since then it hasn’t changed much, as we can see in the “Brazilian viola” which is used for a kind of Brazilian country music called musica sertaneja (countryside music). The shape of the soundbox of this viola today resembles more a small classic guitar. Unfortunately there are very few records of those times, making it difficult to make a better study of those guitars and their makers. It’s known that most of the instruments were made in Portugal, Italy, and France.

The first decade of this century brought three immigrant families from Italy: the Gianninis, the DiGiorgios, and the DelVecchios. These families were luthiers in their country of origin and later they founded the main Brazilian guitar factories which became the backbone of Brazilian-made guitars for nearly eighty years. They made mostly classic guitars and some violins, along with Brazilian violas. They also made mandolins, first with vaulted backs like lutes and later with flat backs, which are used to play choro music.

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