Re-fretting a Guitar

Today I’ll be dealing with a somewhat more advanced repair, re-fretting.  Like neck resets on an acoustic, this is something every guitar will have to face if it’s played for any length of time.  The nickel silver frets are much softer than the steel or bronze strings they come in contact with and those divots they create will eventually cause the string to buzz.

We’ll be dealing with two kinds of frets here.  The traditional nickel silver [I’m including the newer Evo alloy (CuSn15Fe1Ti0.1), a copper alloy that is a little harder than nickel silver and has a gold color] and stainless steel.

We’ll start off with nickel silver.  As I stated before there is no silver at all but an alloy of copper, nickel and zinc.  The nickel content is what is referred to in the percentage, i.e. 18% being the most common in fret wire.

First the tools:  Obviously you will need the same tools as a level, crown and polish with the addition of end nippers in two sizes, standard and small.  I recommend a high quality brand such as Channellocks as they will hold up better and unless you’re really good at grinding I suggest you buy them from a guitar supply because they have to have the face ground flat. You will also need a soft blow or plastic tipped hammer and if you are going to compression fret (more on that later) an arbor or drill press and appropriate radius caul to install the frets. Some manufacturers and builders glue their frets in (I do) so you need a soldering iron to break the joint.  Finally, you will need a fret beveling file.  You can purchase this from Stew-Mac but one can easily be made.

The steps are as follows:

1. Remove the old frets by heating the top of the fret with the soldering iron.  Be careful not to contact the board surface.  I usually cover the body of the guitar with some sort of protection and you can do the same with the board but I usually don’t.  Then use the small nippers to ease the fret out.  Do this by starting at the very end and getting under the fret bead.  Be careful to do a small amount at a time.  The heat from the iron not only breaks the glue but minimizes the chipping that can occur when the dimple on the tang is backed out.  I usually do about a 1/16″ at a time and that is, in most cases, enough to keep the chips to a minimum.  Sometimes the board is old and brittle (very common in ebony boards) and some chipping is inevitable.  Immediately glue the chip back in with a little cyanoacrylate glue and continue on.  If you lose the piece you can fill it with dust and cyano.

2.  Now that the frets are out you must assess the fretboard and the slots.  There is likely wear on the board itself, less so on ebony than rosewood.  Divots from the fingers and the strings is common, especially under the first three frets.  If the board has enough thickness I will try and level it.  If it’s been done before you can expect to run into several problems.  The fret slots may not be deep enough after the board is surfaced.  You may go through the position markers and need to replace them.  In the case of Fenders with curved fretboards (the board is curved on the top and bottom to save wood) you may not be able to re-surface. In the case of maple boards there is the added problem of the finish on the surface.  Maple, unlike rosewood or ebony, needs a finish or it will discolor.  This is exacerbated by the fact that Fender finished the boards after they are fretted.  This means you have to score along the fret and hope the finish doesn’t come up with the fret.  In any case some re-finish is likely so this can up the cost of a re-fret on a maple neck considerably.

Now, if the fret slot is not deep enough you will need to use a back saw of the proper thickness (usually .023″) including the kerf or set on the teeth.  Do not go too far and be careful to maintain a straight and true slot.   If the slot is deep enough you must now remove any glue from the slot.  I found that an X-acto knife blade ground in the shape of a hook will work, but you can also buy saws for this purpose.  All this is complicated by a neck with binding.  You can check the slot depth by using a business card inserted in the slot and marking it with a very sharp pencil.  If it’s not deep enough you must either make a tool by cutting a back saw blade off so that you only have about an inch of blade or buy a specialty tool to get into the slot without cutting the binding.

You can now level the board using a level or radius block with 100 through 320 grit sandpaper.  I start by releasing the tension on the truss rod.  I don’t use anything coarser that 100 because it is too hard to remove the scratches of a 80 or less grit.  After leveling I use a small three corner file to bevel the fret edge to make the fretting easier.

3.  Choosing the proper fret wire is next.  If you’re replacing like with like, just measure the width of the bead and match it.  Several companies make fret wire and between suppliers like Stew-Mac, Luthiers Mercantile and Dunlop to name a few you should be able to find a match.  If this is a new guitar you can take your pick.  A word of caution in getting jumbo wire.  The wider wire is considered the choice of players who like to bend strings, but in reality it’s not the width that makes the bends easy but the height of the fret.  If the fret is crowned properly the string only hits the fret at the top so the width has no practical value.  In fact, as the fret wears and flattens it can cause buzzing and intonation problems because the string is contacting a larger surface.

Prepping the fret wire is next.  This step should not be overlooked.  It should be de-greased using naptha or alcohol.  Then the wire should be bent in a radius greater than the fret board radius.  This helps the fret seat by setting the ends of the fret first and causing the dimple on the tang to go in at somewhat of an angle.  Fret benders are available as are plans.

I then cut the wire to length by making it about a 1/4″ over the width of the slot.  Using a block with holes drilled and numbered it’s easy to keep track of the frets.  If the fretboard has binding you must clip the tang of the fret so that the bead overlaps the binding.  Special nippers are available but you can, with patience, use a fine file.  A quick note about Gibson guitars with the “nibs” on the binding following the fret profile.  This is done before the fretboard is applied to the neck and is not practical to do on a re-fret.

4. The installation of the frets. On bolt necks the easiest way is to take the neck off to re-fret. Just remember to bolt the neck back on as the torque of the screws can affect the neck straightness.   Acoustics can be the most challenging because the area of the fretboard over the body is supported only by the braces of the guitar top.

You can use a hammer to seat the frets by tapping them in from both ends first to the center.  You should use a plastic or brass faced hammer so as not to deface the relatively soft fret wire.  When you get to the body area you can hold a bag of lead shot underneath to soften the blow of the hammer.  Some people take of dimples off the tang and glue the frets in. This can be done by using a special pair of pliers or a set of files designed for the purpose.

I set my frets using the compression method.  This is done with a drill press or arbor press to seat the frets using even pressure.  If you do use the drill press be sure to unplug it first!  I use a caul that is the radius of the fretboard this is chucked into the drill and a platform is attached to the press table.

To glue or not to glue?  I use white or yellow glue to set the frets.  I feel it’s just another step above.  The glue not only keeps the fret in but lubricates the fret slot and fills the space left from the bottom of the slot to the top of the fret tang.  Some luthiers use cyanoacrylate to do this but I find it’s too easy to get the stuff on the instrument and damage the finish.  I wax the board without getting any in the slot.  This stops any glue from sticking to the board.

I apply the glue in the slot with a toothpick and try to avoid applying too much.  I do about four slots at a time, and press the fret in until it’s seated.  This is something that takes some practice but before long you can feel the fret seat.

I use another padded block to place under the back in the area of the head block to support the guitar when I’m fretting over the body.  I don’t like to take the dimples off and glue as I feel it doesn’t give the fret enough holding power, even with the glue.  Instead I use a Taylor fret buck.  This is a massive casting that sits on top of the guitar and clamps to the underside through the soundhole.  This allows me to install the frets over the top without worrying about collapsing the top.

Once the frets are in I allow the glue to dry and clip the fret ends with end nippers.  I use the fret beveling file to put a 35 degree bevel on the fret ends.  Make sure that you protect the top from any damage.

Now you can proceed with the Level, Crown and Polish.

Of course as I pointed out in a previous post on Level, Crown and Polish, stainless steel frets have reared it’s hard head.  Some people find a difference in tone, but I feel that this is very subjective.  These can cost over twice the average cost of a re-fret but you probably won’t have to re-dress the frets for ten years or more.

Stainless can come in several different grades.  Most fret wire is either 300 or 400 series stainless.  Most luthiers like the 300 better because it has more nickel in the alloy and polished up better.  The 400 is greyer in color. End nippers will not hold their edge with stainless and traditional crowning files are practically worthless.  You will need hardened diagonal cutters (even these won’t last long) and diamond crowning files are a must.

Even if you choose not to do your own fret work at least you will be better educated in what it takes to do a first rate fret job.

Cheers,

Mark

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