Here's a simple job that
was deceptively complex. The idea was to replace these heavy Schaller
tuners with new Waverly reissue gears that would be more appropriate for
this 1920s vintage Martin.
First, I had to make a little
puller so I could haul out those bushings that were installed as bearings
on the inner holes. Schaller made them to fit into classical guitar roller
size holes. I mashed over the end of a metal rod to form a small hook.
Then, with a hard pull, I could get the
bushings out. Naturally, these bushings don't conform to any known plug
cutter so I set about making a simple cutter to avoid having to enlarge
these already huge holes.
I chucked a piece of drill
rod into my lathe, and drilled it with an appropriate size drill to correspond
with the holes in the peghead. I've done this job with just a drill press,
but the lathe gives me some insurance against getting the hole off center.
Then I used the carbide
cutoff wheel on my Dremel to form a couple of crude cutting teeth into
the edge of the tube I had created.
Figuring
I'd be keeping this little tool for a future job sometime, I decided to
heat treat it a bit. My only convenient heat source was a small propane
torch, and it doesn't put out quite enough heat, so I laid the cutter
on the element of my kitchen stove to get a head start in the heat department.
Now, we're cookin'.
A quick dunk into cold water,
and the tool has a cutting edge of reasonable hardness, good for lots
of cutting in mahogany.
So, here's the nasty looking
little devil.
And, cut like the Devil
it does. I made a bunch of little plugs by drilling into a thick mahogany
block, without going all the way through. That way, I don't have to worry
about jamming pieces up in my cutter.
Then, I band sawed the pieces off.
Cutting the plugs to approximate
length, I glued them in place, tapping them in with my little ball peen
hammer.
With just a bit sticking
up, it was easy to trim off the excess with my broad knife.
This is the tool that makes this job go
well. Thanks to Don MacRostie and the gang at Stewart MacDonald, there's
a tool to drill slotted pegheads in perfect alignment for new tuners.
This classical guitar drill jig is self centering and has the precise
spacing of modern gears. I had made my own reducing bushing for the 1/4"
necessary for steel string gears, although by now it's standard equipment
from StewMac.
Notice, my new holes are
perfectly centered top to bottom, which is ore than I can say for that
other guy's holes!
And, after just a bit of
touchup, the new gears fit right in place, and looked good.