An Affordable Brass Bridge Stamp

I recently decided to try out a customizable leather punch for sale on ebay.  I’m thrilled with the results.  Wuta Leather offers a customized leather punch at quite an affordable price.  I ordered mine and provided the specifications after they contacted me.  It took about three weeks to arrive.  I added a walnut handle and gave it a test run.  I’m very satisfied with the results.

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A bridge stamp is a great addition for a violin maker, particularly if you take care in the setup of your instruments.  The stamp goes on the side of the bridge facing the fingerboard, on the waist of the bridge.  It’s typically done is an easy to read font, and sized so the text is 1.5mm high.

For best results, hold the stamp in the flame of a tallow candle.  The purpose of the candle is to coat the stamp with soot, not to heat the stamp.  Press with firm against the bridge adjusting the angle slightly without removing to ensure complete contact.  The stamped name will not smudge.  Comment if you’d like to order a stamp through me, or if you’d like more information.

Continuing the Canonne

Work continues on the back of the Guarneri 1743 ‘Il Cannone’ inspired violin.

This tightly famed European maple back and matching neck block will closely approximate the original ‘Il Cannone’.   This beautiful wood should make for a visually stunning instrument.

The downward chevron created where the flames meet at the joint are true to the original.  Guarneri broke with tradition in this aspect of his making – an intentional statement of individuality to set himself apart from the other great Cremonese makers.

The outline is transferred from the mold with a moderate overhang.  The plate outline and overhang will be adjusted with files after this step.  Cutting is done by hand with a #7 blade on the Knew Concepts Jewellers aluminium fret saw.

Jigs: Bridge Jack/Lift

A bridge lift or bridge jack can be very useful for lifting the stings momentarily for making adjustments to a bridge on an instrument that is already setup.

I was disappointed with the cost of commercially available jacks so I made this one on my own.  Two short pieces of coat hanger wire act as guides on each side.  The lifting screw sits on the head of a filled down screw in the lower portion to prevent it from sinking into the wood.  Make sure the tensioning knob is small enough to pass between the D & A strings when placing the bridge jack next to the bridge, otherwise you would have to remove the screw each time!

Note: obviously a bridge jack is not useful in setting  a sound post.  The setter and inspection mirror are sitting next to the bridge jack because they live in the same box 🙂

Jigs: Benchtop Cradle

A cradle is very useful for working on assembled instruments.  Tasks like setting sound posts are easier and less prone to damaging an instrument when the instrument is held in a cradle.

The cradle is no more than a thick piece of wood (or in this case several sheets of inexpensive plywood) hollowed on one side to fit the back of an instrument and lined with cork or leather.  Its also helpful to put something on the bottom to keep the jib from slipping on a bench.

Aside: I keep my setup tools in the old cigar box pictured below.  This are nice boxes and can be found fairly cheap.  Most cigar stores will have a pile and only charge $5 or $10 for the nicest ones, sometimes less.

Jigs: Vee-Board

A vee-board is very useful for fine fret saw work, such as for rough cutting the f-holes, I also find it quite useful for work where the edge of plate (belly or back) needs to overhang, such as using a purfling marker or cutter, or filing edges to shape.

Roger Hargrave outlines how he uses a vee-board in his article Purfling & Edgework in Cremonese Instruments in the library section of his website.

 

Jigs: Edge Fluting

 

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This swivel cradle is ideal for edge fluting.  The cradle rotates in a vice.  It’s designed so that tightening the vice locks the rotation of the jig.

The jig is also useful for final shaping and finishing.  The jig is hollowed so that the inside of plates can be worked as well.

The four corner holders are lined with cork and are slotted so that they can fit a variety of plate sizes.

Cutting the Purfling Channel

I’ve tried a new method for cutting purfling channels, this uses Roger Hargrave’s interpretation of the Stradivari method.  Among Strad’s artifacts, now in the Museo Del  Violino in Cremona, Italy, are two single bladed purfling cutters.  Roger believes that Strad used these to cut independently the outside and inside edge of the purfling groove.

I used this method on my most recent violin and found it worked well on the back, but was especially useful on the top, where year growth rings can cause a freely held knife blade to be pulled into the soft summer wood.

To do this I re-ground two of the blades from an Ibex-style purfling marker to be double edged (pointed) so they could cut in both directions.  A narrow taper ensures the blades won’t over-widen as they cut around the turns and corners.  I then mounted each blade in its own purfling marker.  I added a small brass ‘L’ to act as a depth stop which meant less checking of my depth of cutting.  The cutters worked well, but I did occasionally use my knife.

To setup the cutting position, test with a scrap of wood with the purfling you plan to use for the instrument under construction.  Also in the pictures above you’ll see a file which i converted to purfling picker.

Restoring a Glue Pot

20151026_171723Traditional hide glue was prepared in Glue Pots.  Hide glue is used in making violins for a variety of reasons, don’t take your violin to anyone who doesn’t use traditional glues they could seriously damage your instrument.  Read more about hide glue here.

Before the 20th century and the advent of PV glue, glue pots used to be as common as frying pans.  I found this typical old glue pot and decided to fix it up.  At one point it may have been enameled, this prevented rust from coloring the glue.  I won’t use the glue pot for my own work, but I like to have a 100+ year old glue pot on the shelf to put things in perspective.

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The pot is cast iron, I removed the rust by soaking in vinegar (this will etch the surface and would cause visible damage if the surface were polished, but this pot won’t notice).  I then ‘seasoned’ it with olive oil like you would a cast iron pan.  You can see the final result at the top of the post.  It turned out quite nice I think.

09a0282v1Lee Valley now sells a small stainless steel pot replica which would work well if you like the traditional look and feel.  It can be used with a small electric hot plate or coffee cup warmer which they also sell.