May 19, 2013

Banjo Boys, Chapter 19

This weekend, both Monty and Clint had previous engagements, so I was on my own.  The big news this week was that the clear plastic heads for my banjo and Monty's arrived.  We ordered these a few months ago but because of their non-standard size (11-5/8", medium crown), they had to be custom made.

The first job for this weekend was to re-fabricate my tension hoop -- the hoop that is pulled down by all those hooks and stretches the head across the rim.  I had already made this hoop, but I made it slightly too small.  I bought some more brass to start over.  I now have the advantage of having the head to use as the gauge for the size of the hoop.  So the first thing I did on Saturday was to fabricate this ring and prepare it for Dan Shady to silver solder the ends together.  The ends are cut at an angle as shown to provide a larger surface for the silver solder to adhere to.

As soon as I laid my plastic head in place, I realized that I had a problem.  The gap that exists between the Rim and the base of the neck, intended to accommodate the hoop of the head, was too narrow.  The edge of the head couldn't slip down into the gap.  So I knew that the second job for the weekend was to somehow widen that space.
I removed the neck from the rim.  I then drilled a small hole in the dowel rod at exactly the midpoint of the rim (5 13/16" from the base of the neck).  This gave me a pivot point from which I needed to deepen the radiused cut that already existed in the bottom of the fretboard.  I clamped a board on my drill press that had a nail of the proper diameter to fit in the newly-drilled hole.  I then mounted a small sanding drum in the drill press, adjusted the board so that the sanding drum would take a thin slice from the existing arc and swung the neck back and forth across the abrasive surface.  I had to repeat this a couple more times, readjusting the position of the board each time.  I finally dressed up the bottom edge of the cutout area with some precision chisels.  Then I stained the newly-exposed surfaces to match the rest of the neck.  I think the result speaks for itself:

So now, I have a banjo with a clear plastic head in need of a tension hoop, to be completed this week.  I also need to figure out exactly how I'm going to use my Navy spoons as tension hooks and how I'm going to make the tailpiece out of the meat fork.  We're getting close!

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