Friday, June 29, 2012

Detailing the Jauch Triple Rose

After repairing one of the two damaged theorbos that I described in my last post I was able to get back to work on the Jauch triple rose. I still had to lay out and cut the decorative border, round the edges of the organic features, vein the geometric elements and cut the center emblem.

There are different styles and treatments of chip borders. The one that I am demonstrating can be subtly changed by varying the individual elements: the width of the ring and/or the number or angle of the individual pieces. Since the top rose is smaller than the other two I made its border slightly narrower. I work this out by what looks good to me -- a fraction less than 3.5mm for the small rose and a fraction more for the larger two.

I use a template made of card stock marked off in 5 degree intervals around a pair of circles that exactly represent my rose border. It is then a simple task to punch the diagonal lines. Here I am using a 4mm micro-chisel.

Then I cut the relief on each segment. Here I have worked part way around one rose. The tool is a 3mm micro skew chisel. The blade of such a tool is angled at 30-45 degrees. Held at an angle to the face of the belly opposite corners of each segment are removed, thus creating the relief.

I think that veining, creating a "V" groove in the geometric elements of the rose, is the most difficult. First it is necessary to scribe two straight, parallel lines -- not to close to the edge of the design but not too close together either. And deep enough to leave a nice impression. Then, holding the knife at an angle, slice off a thread of wood the full length of the element as demonstrated. Repeated attempts will result in a frayed, untidy "V". Since the design runs at various angles to the grain of the belly some cuts are easier than others. Across the grain calls for a delicate touch as the wood is very fragile. With the grain requires a firm, bold hand as the knife may catch on the grain. At an angle to the grain the knife slips along easily and satisfyingly.

The next step is to detail the organic elements by slicing off the top edge of the veins and petals. This gives them a delicacy that contrasts with the geometry of the border and veined members. The center emblem is created by cutting a series of slightly curved, crossing veins.

Cutting one rose is a lot of work. Cutting three is -- well -- three times as much. I'm happy and relieved when I finish.
They are beautiful.

But now I can get started on deciding how I want to bar the instrument. How best to bring out the inherit character of wood and design.

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