10/2/13

Refretting a Vintage Martin 1T Ukulele

Buckle up, dear reader, this will be a long post with a lot of pictures.  But hopefully it will be fun!

When we left our mild-mannered Martin ukulele, it had just gotten a K&K pickup installed.

Now it's going to get new frets.

I think I've posted pictures of my Japanese fret slotting saw before.  Pretty scary looking, but just the thing for...well, cutting fret slots.  You can see how big it is compared to the ukulele.

The saw has a handy-dandy depth stop that can be mounted on it.  What I need to do is cut the existing fret slots just a bit deeper and wider than they already are.  We're talking thousandths of an inch (or a millimeter...) here.

The new frets have a tang (depth) of .054 inches.  The existing slots are a little shallower than that.  So I set the depth stop to just a hair over .050 of an inch.

Then I carefully recut the slots.

After I did a few, I came up with this method:  carefully seat the saw into the slot, then slowly pull it through.  I did a couple slots where the saw wasn't exactly lined up in the slot, so I accidentally cut a shallow slot next to the original.  They were easily filled (2 of them), but I took more care going forward.

Now for the piece of resistance.

This is the Stew-Mac 'Jaws' fretting pliers tool device.  I've thought about buying one for a long time, and I finally bit the bullet.  (If you follow Argapa Ukuleles, you know that Sven is experimenting with pressing frets in too.)

Basically, Jaws is a long-nose locking plier that Stew-Mac has adapted with a lower caul to go around the bottom of the instrument neck, and a device on the top jaw that holds a caul radiused for a given fingerboard.

It ain't cheap, but it's amazing.

The basic tool is a Facom 960 Long Nose Hinged Tip Large Capacity Lock-grip Plier.  As I said above, the folks at Stew-Mac modify it to turn it into a tool for pressing in frets.

The 960 is a molybdenum steel tool made in Facom's Laissey, France, plant, "the largest plier factory in France," according to their web site.  Which makes me wonder what the largest plier factory in Yurrup is?

Facom has a good reputation and I've always been curious about their tools.  Side note: they're a sponsor for the Toro Rosso Formula 1 team - the 'junior' Red Bull Racing team.  I think they used to be a Ferrari sponsor as well, but I could be wrong.

Is all of that useless information or what?

Here's the business end of Jaws.  The bottom caul is nicely padded so as to not damage your vintage geetar, and the top is the caul press.  I'm using a flat caul, but Stew-Mac gives you a bunch of other radiuses - 7.25, 9, 12, etc.  Your basic Popular Guitar Fingerboard Radius Selection.

I think you can get the idea of how this thing works from that picture.

Here it is in action.  You adjust the tension just so (juste pour l'ajuster) and appuyer sur l'fret
(squeeeeeze the fret) into place.

Wow.  Where have you been all my life?

I am a terrible fret-hammerer.  This is the answer to my dreams.  Perfectly pressed frets!  

Je suis tellement heureux avec cet outil!  Oui! Oui! Oui!

Unfortunately, not everything is rainbows and unicorns.

The frets over the body still need to be hammered in.  Whap whap!  D'oh!

And naturally the ends of those frets are a bit loose so I need to wick some thin CA into the slots to get them to fully seat.

However, jaws will work its wonders on 2/3 of a neck...and it will do an entire bolt-on neck.

 Next we trim the excess off the fret ends.  These cutters work great on a guitar, but they're a little too big for an ukulele - they can't get super close to the fretboard.  Oh well.

Then a quick level of the frets.  I used 320 paper and didn't take much material off at all.  They were quite level, at least on the ones that were pressed in.

Then I take my homebrew fret end bevelling tool and have at it.

Geez, these frets are really small.

Since the tops of the frets are flat from the levelling, they need to be re-crowned.  The top surface has to be round in cross-section so the string only contacts one point on the top of the fret.  That prevents buzzing and makes the intonation acccurate.

I use a small crowning file on them.  We're getting close now.

I use a tri-corner fret file and a small fret end file to smooth any rough edges that could snag your hand when playing.  I filed the very end of the frets and also the sharp corners indicated by the arrow.  Just a few file strokes usually does it.

The finishing touch is to polish the frets and fret ends with the wonderful fret erasers.  These are little abrasive blocks that run from 150 to 1000 grit.  Makes the frets super smooth and also shiny.

All done.  Hard to photograph, but you can see the fret ends are nice and smooth.  The fingerboard is dead flat and so are the frets.  It should play very nicely.

Now, I contemplate my next fretting job.

1 comment:

  1. You bought the Jaws? Crikey, I want one too. Mine works, but it is fugly.

    ReplyDelete