Installing Waverly Tuners on Martin Ukulele

There are just a few things left to do on the Martin 1T.  One of them is to install new tuners.

The tuners on all these old Martins have lasted a long time and work well, but they do have one issue that's not easily corrected.  The picture to the right illustrates it.

On the left we have a disassembled Martin tuner taken apart in an 'exploded view' fashion.  I'm pretty sure these were made by Grover.  It's a well-made, sturdy tuner.  However, there is one flaw in the design.

If you look at the tuner button at the bottom, you'll see it was molded from one piece of plastic.  The part that slides into the bushing is a square shape.  The bushing also has a matching square in it - this is what drives the post when you turn the button.    The problem with the design is that the square drive is made of plastic.  Over time, when the button gets loose and slips, the plastic turns in the bushing and the square edges are gradually worn away to the point where the button will just turn no matter how tight the screw is, because the corners have become rounded.

I "fixed" one of the tuners on my ca. 1929 Martin by just gluing the button to the bushing with JB Weld.  However, that's only a temporary fix - the button will slip again over time.

When one of the tuners on this other (ca. 1940) ukulele started slipping, I decided to replace it with some new Waverly tuners.  This is a new design friction tuner, not geared, but with some improvements, yet resembling the old friction tuners.

You can see the Waverly on the right also 'exploded.'  The bushing has a slot that the button fits into, and the button is ebony.  There is also a spring to maintain tension, which means it should not require tightening as much as the old Grovers.

However, the Waverlies (Waverlys?) are a bit smaller, and as I found out, require a little finesse when putting them in an old Martin.

In reading up on the Waverlys, I learned that there are two different angles on the top and bottom of the tuners that are designed to snug into a countersink.  Stew-Mac recommends their bridge pin hole chamfer tool for this countersink.  However, the angle on that tool is 82 degrees - a standard countersink angle.

Since I wanted the tuners to look right, I got the proper 60 degree (for the bottom section of the tuner where it meets the underside of the peghead ) and 100 degree (for the top side) countersink bits.  You see them here - I got them from McMaster-Carr.

Here's where a little measuring FIRST comes in handy.  I eyeballed the tuners and the headstock and assumed they'd fit perfectly.  Never assume.  Always measure!

So after assuming they'd go in with no problems I set about making the countersinks.

Here I made a slight countersink for the top bushing with my new 60 degree bit.  I did some tests on scrap first (see the picture above), and found I only needed about 1 to 1.5 turns on my hand drill to make a nice chamfer for the bushing to sit neatly in.

So I made the same chamfer on the top of the headstock, and used the 100 degree bit for the back.

The bushings fit perfectly and looked good.

However, the thickness of the headstock is about 1/32 of an inch too thin for the bushings to sit down perfectly in the chamfers!  In other words, when I put a tuner in and tightened it up, there was vertical play in it.

Argh.

Measure first!

I really wanted the bottoms of the tuners to fit well, so I decided to use some plugs in the top of the tuner holes to make a new surface for the bushings to sit in.

This picture probably explains it better.  The chamfer made the top bushing sit just a little too deep in the hole.  It looked great - the outside edge sat perfectly level with the top of the headstock.  But the way the bushing dishes down made the effective thickness of the headstock too thin, so the tuner wouldn't tighten down all the way.

The plugs are about half the height of the holes - and they give the bushings the proper height to sit on.

I drilled out the plugs so the tuner shafts could pass through them, and I sanded the tops of the plugs down flush to the headstock.

That sign painter's tape works great to safely mask off a surface you want to protect.

Then I stained the plugs.  You really won't be able to see them when the tuners are installed, but I didn't want to take any chances.

The shade of the stain is 'Red mahogany.'  Not even close.  But dark is good.

I think I made a decent recovery.  Here are the new tuners installed.  You can see the downward 'dish' of the top bushings.  I was a able to do a tiny chamfer on the plugs, but the bushings still sit above the surface of the headstock.

They'd look great in a chamfered hole, but I just don't have enough thickness to work with.  Still, they don't look bad - from the top they look great.

The back side is a different story.  The body bushing fits down nicely into a 100 degree countersink.  I left this one up just a little for this picture so you could see how the bushing angles inward - that's what you want to snug down into the hole.

Here's the back with all four tuners installed.  They look great I think.  But they're much shorter than the orignals!

You can also see how the ebony button fits down into the bushing.  This is a much better design than the old style.

They'd work really nicely on a new build.  Now I just need to finish the ukulele so I can try them out.

Update April 20, 2014:  I've replaced these tuners with some Gotoh UPT Geared Planetary tuners.