Checchucci Guitar - Final Installment

Michael Manderen finally gets to try out my model of the Jacopo Checchucci 1628 guitar (Museum of Fine Arts, Acc. No. 2001.707, Boston USA). As Director of Admissions for Oberlin Conservatory Michael travels extensively auditioning prospective students  but during the summer he relaxes by playing weekends at regional medieval fairs. I have built a number of instruments for Michael and when he asked me to build an Italian baroque guitar he agreed with my plan to research and build a model of an instrument that had not yet been replicated. This was to become a two year adventure. I reported on my visit to the museum in this blog on April 25, 2012. Later in the year, November 6, I posted a down-loadable drawing of the instrument. Six more posts detailed its construction including new techniques (for me) while others chronicled various trials and tribulations that I encountered along the way. This final installment tidies up a few loose ends.

The original guitar was constructed with a short neck. I thought this arrangement was impractical so I increased the string length to 65.5 cm. This allowed for one more fret on the neck.

The bridge on the MFA Checchucci is a modern replacement. I didn't find the trident motif convincing, but I did want to retain something of the guitar's aesthetic at this point.

So I borrowed Jacopo's design of the top part of the rear arabesque to serve as the inspiration for the moustache of my bridge.

The triple stringing lines frame every element of the guitar's construction.

Except for the horizontal lines on the side ribs the triple stringers are part of the aesthetics of the original guitar.

 I was fascinated with the design of the peghead and I described its construction in detail in a post on March 11, 2014.

I think the grainy Kingwood figure gives an organic touch to the peghead's geometry.

Although I seldom do this type of work, I think my favorite (and most challenging) part of building this guitar was making the borders. I had to figure out the new techniques for cutting, shaping and aligning the individual pieces. There were problems along the way but it all worked out.



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         All photos by the author.

Louis Panormo No. 2154, 1834 - A Restoration

It looks like Jerry Willard is happy with the restoration that I did on his Louis Panormo guitar. I hope so. This is the second time in two years I have done serious work on this guitar. Last year I replaced the fingerboard which resolved the problem of the guitar playing badly out of tune. My blog post from April 5, 2013 describes this work. This time the problem was more serious.

Jerry had just returned from a gig in Greece and opening the guitar case discovered that the bridge had split right along the pin line -- unfortunate, but good timing!

Jerry Willard photo

This type of bridge failure is common. Bridge pins are tapered over their length and are intended  to fit snuggly in their holes. The pressure they exert on the surrounding bridge wood is small but over time, combined with the pull of the strings, the wood will often split. There was no question of gluing the bridge back together. It would need to be replaced.

The front half of the bridge was completely separated from the soundboard and fell off when I removed the strings. The rear half was still in place as were both bridge arms. These latter pieces seemed to have been integral with the bridge block at some time but had broken off during a previous incident because they remained attached to the top when I removed the remains of the bridge block.

The condition of the soundboard under the bridge was frightening. It was worse than I expected. Obviously it had come off previously and probably more than once. On one occasion large chunks of the top had been ripped out in the area in front of the bridge pins and had not been replaced before the bridge was re-glued. Glue from this operation had collected in the open cavities. Curiously, the ripped out section in front of the 'A' string (second from left) continued pass the front of the bridge. That area had been filled in cosmetically. It is visible as a darker rectangle. Also thin layers of wood were lifted as seen in the center of the photo. But the most troubling sight was that the surface of the raw wood was a good third of a millimeter below the surface of the varnished soundboard. Such a clear line is delineated across the front of the bridge as a result of a technique that some luthiers use to ensure a tidy appearance of the varnish around the bridge. Guitar makers often apply the finish to the top before the bridge is glued on. Afterwards the bridge is held in place and a shape knife line is scribed around the outline of the bridge. The finish in the area can then be easily and precisely removed with a hot knife leaving a clean surface for the bridge. The mistake here was that the hand that held the knife was too clumsy and too deep a cut was made. When the bridge joint failed it took a big chunk of top wood with it.

 I had recorded measurements of the guitar previously so I knew the area around the bridge was only 2.0mm thick.  I thought that if I just replaced the broken bridge and it came off again, which was likely considering the lack of structural integrity of the soundboard, it would cause even more damage. I started to repair the damage by squaring up the ripped out sections in front of the pin holes and filling the cavities with new wood. Other less damaged areas were re-glued and levelled.

The top had sunk slightly below the side rib level and the bridge canted down on the front edge and up at the rear. This was in spite of the fact that the three center fan bars had been replaced and a bridge plate added in the not to distant past.
I decided to replace all seven fan bars and at the same time to re-dome the soundboard.  To get started I needed to remove the back.

I did this by wicking de-natured alcohol into the joint with the side ribs using a thin palette knife. It came off easily except for the area of the slipper foot that required more patience.

I removed and preserved the original fan bars, not to reattached them but as artifacts. Part way through removing the newer fan bars I discovered the reason they had not prevented the top from collapsing.  As the photo shows the bridge plate was continuous between the 2nd and 5th bar. The central bars were notched to fit over the bridge plate. I realize that this is sometimes a regular procedure for modern classical guitars but their fan bars are considerably larger. As it is, this procedure removed half of the substance and strength of the bars in a critical location.

I made new bars from quartered spruce all measuring 5.25mm high and 4.75mm wide. I notched the bridge plate to receive the center three bars with a snug fit and glued them in place upside down on a solera  This is a concave assembly platform and the technique is the traditional Spanish method for gluing the fan bars. The fan bars and soundboard are pressed into the concavity of the solera resulting in a domed or arched soundboard that enhances the tonal characteristics of the instrument. It also makes it more structurally stable, a key attribute. Before gluing the back onto the side ribs I tapered the fan bars from end to end leaving them highest at their midpoint and reduced to zero at each end. The two edge bars originally were only 2.5mm at their highest point with the center three measuring 5mm. I gave mine a little more heft starting at 3.2mm and increasing each pair gradually to 5.25 for the center bar. Once I was satisfied  I glued the back in place.

Jerry Willard Photo 2013 (enlarged)

Now that the soundboard was finished I was back to the original problem -- replacing the bridge. This is a photo of the original  bridge as it appeared last year when I first received the guitar to correct its false intonation. The front peaked edge of the bridge acts as a saddle. At some point it had been altered perhaps because it broke off. Regardless of the reason, two or three millimeters of its height were removed leaving a flat surface. A new rounded piece of ebony was substituted. Part of the work that I did last year involved replacing this piece with a similar piece but one that compensated for the intonation of each string.

This is the bridge that I made to use as a replacement. Its design differs from the original in two important aspects.

First, it has a separate saddle that can be raised, lowered or exchanged. It is important to me and to Jerry that the guitar play perfectly in tune. The top of the saddle is sculpted to provide the necessary compensation for each string. The second feature is the scalloped extension to the rear of the bridge. Panormo did use this feature but I thought the build date for Jerry's guitar predated its use. Since I thought it was important to provide as much gluing surface for the new bridge as possible I included this feature. Also, I shaped the entire bridge including the side wings from the same piece of ebony. Because the surface of the top in this area was irregular I shaped the bottom of the bridge to fit the unique contour of the soundboard and glued it in place, including into the depression that I described earlier.
This completed the job but the story does not end here. Jerry posted a series of photos of his repaired Panormo on Facebook that drew a number of responses among which was a question of concerning  the date of his guitar . Jerry and I believed it to be 1831 and build number 2152. Chris Susans, noting similarities between Jerry's guitar and his duet partner, Wendy Jackson's 1834 Panormo, asked Jerry to post a photo of his label.

                                                There it is: 1834 and build number 2154.

                    By the way. My blog passed 50,000 page views this past weekend. Thank you all.

Christoph Koch Theorbo - A Photo Album

I finished another Koch theorbo last week. This is the same model that I described in posts from 9/20/2013 and 4/15/2013.
The lute was commissioned by Tony Elitcher, Adminstrative Director of the New York Continuo Collective.

http://www.continuony.org/

The bowl is constructed from kingwood as is the original lute with holly
spacers between the ribs.

I inserted a larger photo to show you the different woods that I used on the veneer of the neck and extension. The striped neck veneer is assembled from black Gabon ebony alternating with pieces of kingwood left-over from the rib material with holly spacers. The veneer on the back and front of the extension is African Blackwood. This wood has a brownish tinge to its blackness. The sides of the extension are American Walnut. The back of the extension is rounded by 3mm or so and  then bent in the opposite direction to form the joint with the neck.

Blackwood is brittle and I had trouble bending the wood in two directions so I made a cut through the veneer before I glued it to the extension. After the glue dried I widened the cut and inlaid a wedge of holly topped by a heart. As with much of historical lute making this is an elegant solution to a troublesome procedure.

I carved the theorbo heard from a small block of poplar and test fitted it precisely to the end of the extension before painting it a semi-gloss black to simulate polished ebony. The head was then glued and screwed in place. The screw heads were hidden by plugs. The extension, front and back, is edged with holly.

I adapted a portion of a familiar renaissance rose pattern rotating the axis of the smaller rose by 1/6 to enliven the assemblage.

The rose and bridge of the Koch are placed a little lower on the face in comparison to other theorbos that I have built. The sound has a silvery quality that I attribute in part to this design.

Schreiner's Lutes and Guitars March Update

CATCHING UP

 I have been unhappy with the frequency that I am able to publish posts. When I started my blog two years ago I was able to publish twice a month on average. My topics were generally uniform: following one instrument through the different stages of construction until I was finished. For me this was satisfying and I know you enjoyed my it because my page views increased month after month.

That changed about a year ago when things became disjointed. It is my fault because I take on too much as I always seek new challenges and I have trouble saying no to clients. Projects pile up and I get myself in trouble. This affects  a lot of things including my blog posts. It is difficult to keep continuity from one post to another.

Occasionally I have published updates but now I am going to try to make them a regular feature. This will be just what the name suggests, news about the progress of my projects but also about daily events  in my work that I think you will be interested in. Today is the first under this new format.

The four photos represent the projects that I'm working on daily or those that are not far from my thoughts. The triple rose belongs to a Koch theorbo, the same model that I built last year for Adlai Stevenson High School in Illinois. I finished cutting the rose before dinner so tomorrow I'll bar the top. The second photo is the Checchucci guitar. I finished the border that is composed of bone parallelograms and black epoxy. I'm sawing out the moustaches for the bridge and then it is on to finishing. The lute is a model of C. 45, the Tieffenbrucker archlute in Vienna. I am building it as an eleven course. It is awaiting its rose and belly. The Panormo guitar in the fourth photo now has its back but it will be a few weeks before much else happens to it.

EVENTS

A recent visitor to my shop was Ghareb El Tally, a lutenist/guitarist based in Salzburg. He is in Toronto for a few months and I met him when his archlute needed some work. When he mentioned he had a Roudhloff guitar from the 1840s (Ghareb tells me the guitar is dated 1815, edited April 5 ) converted to an 8 string I asked him to bring it by so I could see it.

Ghareb El Tally Photo

 Ghareb found the guitar in junk shop in miserable condition. Deciding that it could not be restored he had a Viennese guitar builder do the conversion. The back and soundboard were salvageable, the side ribs were re-contructed and the original neck was saved as a artifact.

This style of conversion is often done to modern six string guitars and the work that Ghareb had done follows the same method. The body was fitted with a classical guitar style neck and fingerboard widened to accommodate eight strings and a slotted peghead with mechanical tuners. A modern bridge completed the conversion. Since the back and belly were original and unaltered I was interested in recording their dimensions. I traced the contour, determined the original harmonic bar locations and with a magnetic probe measured the thickness of the back, top and sides.

A few days ago I was offered the opportunity to examine and measure an 1828 Panormo guitar that is in original condition. This is terrific because I have the guitar for a few days and I can study it at my leisure. I don't doubt that I'll have more to report on this instrument in the future.

Checchucci Guitar - Making the Peghead

Jacopo Checchucci MFA Boston, author's photo

 Even without the inlaid ivory arabesque of the original the peghead design is graceful and interesting. It is also fairly complicated to construct accurately.

Face view

A central panel in ebony is surrounded by a border of lighter wood  (I used Kingwood) that is edged with two triple lines of holly (ivory on the original)/ebony/holly mitred at the corners. The face and rear share the same design.  This border makes an elegant frame for the ten peg holes that pass through it. But there is very little space for error in aligning the two decorative panels.

Rear view

The photo below shows the end of the finished peghead.  Note that the laminates that are visible on the edge of the peghead are not continuous across the its width.

 Often fancy pegheads are assembled from thin veneer stacked one on the other. That is not the technique that Checchucci utilized. He constructed the decorative panels of the face and rear on a plain wood core. His trick is that he uses the edges of the core to establish the outer edges of the peg hole border. This ensures that the front and rear line up properly. The exposed end of his core was painted black to match the ebony over-lay. I treated mine differently as I will soon explain.

 At left, I made a poplar wood core and cut the "V" joint to fit the neck.

Rear view of the peghead

In the photo at right I have already assembled the decorative panel on the face and I am continuing on the rear. I glued an ebony plate in the proper location on the rear of the peghead core, but rather than trying to get it in exactly the right location relative to the finished panel on the face, I made it slightly over-size. Then, using the edges of the core against the guide of my miniature table saw I trimmed it exactly to size. The cross cut at the end of the ebony plate was achieved using the table saw guide too. Checchucci could not have accomplished this work as quickly but he obtained the same result probably by laying out the precise lines using a marking gauge and then trimming the ebony plate with a veneer saw rigged with a guide.

Once the ebony plate is precisely trimmed it is a fairly simple manner to assemble the peg hole border so that it fits exactly to the edge of the core block. While Checchucci painted the end of the core black, I cut my core even with the top edge of the peg hole border rather than extending it and added a solid ebony block to the end instead. That is seen in the photo at left



The last element to be added to the core is the laminated edge piece that will be shaped into the characteristic scalloped edge. The stacked layers are clearly visible in the end view of the peghead shown in a previous photo.

When I examined the original guitar I thought the method of construction using a core made of common wood was an example of a historic luthier going to a lot of effort to save valuable material. Instead it turned out to be a clever method to solve a complicated construction problem. I am always amazed to find examples like this.


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