TALON

The silver heel plate or ‘talon’ is about half a millimeter in thickness and it is fit in a shallow channel cut with knife and chisels to accommodate it. When the silver heel is fit and bent into place, the forward edge is squared perfectly straight across where the pearl slide must join it perfectly. Then it is glued and riveted with small silver pins.

At this point the dovetailed channel for the pearl slide is completed and the mortise and channel for the hair is cut freehand using different chisels. The pearl slide or ‘recouverment’ is then fit and trimmed so it fits perfectly on all sides. Finally the bottom of the frog and the heel is filed so all parts are flush with the ebony and smooth. The pins, which have been left proud, are filed off at this time and usually disappear. The pins on a new bow are tight and very difficult to see but over time the miniscule movements of the ebony frog due to changes in humidity rock the pins slightly. So in older bows the pins are usually noticeable.

The frog is now well advanced and all that remains is the underslide or ‘coulisse’ where the frog joins the stick. Here a silver lining is usually fit and pinned in place and a bronze eyelet screwed into place. At this point the frog is complete and ready to mount on the stick but the polishing will wait until the bow is nearly completed.

CELLO BOW

A cello bow is now in process and as with the violin bow we make the fog first. This is because the frog needs to ready to mount on the stick very early on in the process. Since I covered the frog making process in earlier posts I’ll only cover what is unique to a cello frog. The cello frog has a rounded heel or ‘talon’ so this necessitates a different approach in that area. The amount of curve or radius of the heel varies quite a bit between bow makers and in general the earlier 19^th century bows have a bigger radius or are more rounded. There is an aesthetic and stylistic relationship between the curves of throat and the curve of the heel. Since the length of the flat area on the bottom of the frog determines the length of the pearl slide, the rounder heels have a shorter slide all things being equal. In this case our radius is relatively large. The tighter heel curve of late 19^th century makers like Lamy was a bit easier to make and made possible a longer pearl slide since the flat area on the frog was longer.

Once the frogs heel is rounded we fit the eyes in the frog sides and in this case we are using a eye ringed with silver or ‘grain et cercle”. . To receive the ring, a narrow groove is cut with a special drill bit, which cuts the recess for the pearl eye at the same time. Each bow maker makes these bits themselves to the requirements of their taste and style. Francois Tourte was probably the first to make this type of eye and to begin with the ring was fairly heavy, getting finer during the course of the 19^th century. To make this eye a thin strip of silver is cut, bent into a ring and soldered. It is then put on a tapered rod or mandrel and hammered to the correct diameter. It is then filed until it fits snugly into its groove. The pearl eye is filed to fit and glued into its recess followed by the ring, which is hammered lightly into place. When the glue is set, any silver sitting proud can be filed off flush with the sides and the eye is completed.

COULISSE

The pearl slide slides into a dovetailed slot called the coulisse at the end of which the silver heel is glued and pinned. Techniques passed on for generations allow this to be done freehand with great accuracy using two chisels. The pearl slide is made of a thin abalone sheet glued to a strip of ebony. Originally the small silver heel was also attached to this ebony strip and formed a joint with the larger silver heel running down the back of the frog.

But later both parts of the heel or 'talon' were glued and pinned together leaving the pearl slide independent. The heels are pinned by drilling a fine hole through the silver and into the ebony. Then a piece of silver wire is filed to fit and riveted with a small hammer.

Under the pearl slide, another channel leading to a mortise is cut to accommodate the hair, which will be secured with a wooden wedge.