Yahoo Tuning Groups Ultimate Backup tuning Re: guitar refretting FAQ

Here is a draft of the guitar refretting FAQ. I will have replaced my
old tutorial with an HTML version of this FAQ at
http://www-math.cudenver.edu/~jstarret/guitar.html by the end of the
day.

Q: How can I convert a regular guitar to a microtonal one?
Q: How can I make a fretless guitar?

A: Refretting a standard guitar is not all that difficult
if you are patient, careful and have the right tools. Although a
functioning microtonal guitar can be made with fewer specialized tools,
and with less attention to detail, the following is in my opinion the
minimum necessary to do a professional job, one you could charge money
for and have a satisfied customer.
Making a fretless guitar is easy: just follow the first part of the
directions, before we mark and cut the new fret slots. You will need
only items 1,3,4,5,6,9,10,11,14,17,19 and 20.

You will need some (see above), or all, of these tools and
supplies:

1. A 40 watt soldering pencil
2. A fret saw
3. A fret puller
4. A long sanding block available from an auto body supply
shop, and sandpapaer to go with it, in 120, 220 and 320 grit
5. A small (6" by 3") sanding block
6. At least one sheet each of 40, 80, 120, 220, 320, 400 and 600 grit
sandpaper
7. A weighted plastic or brass faced hammer, or, alternatively, a ball
peen hammer with a piece of leather glued to the flat face
8. A ruler marked off in hundredths of an inch (at a good art supply
store or the mechanical drawing section of a university book store)
9. Several tubes of super glue
10. Single edge razor blades
11. X-acto knife with narrow (scalpel blades are the best) and wide
blades
12. Jewelers files and/or nut cutting files
13. A flat smooth file about 10" long and and 1" wide. Sight down a
number of files if you can to find the flattest.
14. Paste wax
15. Fret wire (available from Luthier's Mercantile,
Stewart-MacDonald, GHS strings, or other sources)
16. A mechanical pencil with .5 mm lead
17. A set of new strings
18. An X-acto razor saw
19. Phillips and flat blade screwdrivers
20. Small socket set or small crescent wrench
21. Artist's masking tape

There is a list at the end of this article of suppliers for these tools
and supplies, and some suggestions for makeing some of the tools
yourself.

Removing the old frets:

Remove the neck from the guitar if possible, and remove the tuners and
nut. Do not loosen the truss rod unless the neck is significantly back
bowed (back bow is when the center of the neck is higher than the ends).
You want the neck to be flat or have the slightest back bow when you do
this work. If the neck does not come off, remove the tuning pegs (except
on a classical guitar) and cover every part of the face of the body with
paper affixed by artist's masking tape. I recommend artist's tape since
it is not as sticky as painter's tape and is less likely to leave gum on
the finish, or even pull some of it off. This paper will protect the
finish of the top as you work on the guitar.

Wax the fingerboard and back of the neck thoroughly with paste wax
(Johnson's or other) and let it dry. Do not buff. This wax coating will
help repel the super glue that will inevitably drip where you don't want
it when you are gluing in frets or repairing fingerboard chips.
Heat the frets with the soldering pencil to remove old glue. I have
found that about 8 seconds at three evenly spaced positions on the fret
is sufficient. Hold the soldering pen against the fret with the flat
part contacting as much fret area as possible. Start at one
end of the fret and move in as the fret is being pulled. Immediately
after heating, place the end of the end nipper at the end of the fret
and squeeze until the fret has lifted up enough for the nipper to move
in a little. Move in a little and squeeze until the fret raises up a
little more. Keep this up until you have moved the nipper all the way
across and the fret is out of the slot. All this time, the soldering pen
is moving ahead of the nipper.

Little chips of wood will inevitable come out as the tang of the fret
lifts out of the slot. If you should remove a large chip by accident,
immediately replace it and glue in place with super glue. Should you
lose a chip, the hole can be filled with super glue and wood dust. Most
hardwood dust is slightly basic and will cause super glue to harden
almost immediately (much as will saliva, blood, sweat and tears). Place
a little super glue in the hole and cover with sawdust from the same
kind or lighter colored wood than in the fingerboard you are working on.
You can get a little dust by running the saw blade through an empty
fret slot. You are just going to fill it with wood dust anyway. The glue
will wick into the dust and harden very quickly. It takes a little
practice to get just the right amount of glue and dust. I recommend
gluing chips back in right away, and filling holes when the frets are
all out.

Filling the old slots

Now that the frets are all out, it is time to fill the fret slots. If
you are refretting to an octave equivalent tuning, it is not necessary
to fill the octave fret. First, run the fret saw through the slots to
remove any remaining glue or obstructions. If you have a bound
fingerboard, run the tip of the saw through from binding to binding and
blow the dust out. If you have a fingerboard made from dark wood, there
are several good ways to fill the fret slots. If you have a maple or
other light wood fingerboard, there are no really good good ways I know
of to fill the slots, as filled fret slots are always darker than maple
even if you fill them with maple veneer (although see ****** below for a
method I have recently had some success with). The glue lines at the
edges of the fret slot almost always show up dark. I will list the four
best
ways I know of filling dark wood fret slots.

Method 1:

Find a strip or page of veneer of a wood that is the same color or a
little lighter in hue than the wood from which your fingerboard is
made. Get veneer as close in thickness as you can to the thickness of
your fret slots. Cut strips of veneer a little wider than the depth of
the fret slots and as close as you can to the exact width of the guitar
neck at the fret slot you are filling. It is difficult to cut off
protruding ends without marring the finish on the side of the
fingerboard. Do the fret closest to the bridge first for practice. If
you mess it up, it won't be noticed as much as the first fret, for
instance.
Place the veneer in the fret slot and carefully wick a small amount of
glue into the wood between the veneer and the fret slot. Make sure that
all the surfaces are bound, but don't put glue into the side of the slot
yet. With luck, the glue will wick into the end of the slot by itself.
When the glue is dry (to speed this up, you can us Hot Shot or other
commercial super glue accellerators available at hobby shops or through
Luthier's Mercantile), carefully slice off the protruding veneer with
the razor blade by pulling the blade at a 45 degree angle to the
fret slot with the blade as flat as you can against the neck. A series
of short strokes is best, and be careful not to cut into the
fingerboard. You will not remove all of the veneer on the first pass.
Repeat the cutting process until there is barely any veneer protruding.
Place paper under the neck to catch the sawdust for later use. Sand the
stub with the grain of the neck using the small sanding block and 120
grit paper. When the fingerboard is smooth here, brush off the dust with
an old toothbrush and inspect your work. If you think you can improve
your technique, do the next fret slot down.

When you are confident that you have the knack, fill all the remaining
slots with veneer, glue, cut and sand. Brush off and inspect your work.
There are probably a number of little holes you missed. Fill these with
wood dust and super glue. Remove the old position markers by
drilling them out, being careful to go no deeper than necessary (you
need that truss rod!). Place a little glue in the bottom of the hole and
cover it with wood dust. Fill the hole to the top with wood dust and
tamp in, leaving only the slightest crown. Wick super glue into the dust
and let set. This will take a few minutes, and the fillet may even smoke
a little as the glue sets up.

When everything has hardened, sand the whole neck with the long sanding
block with 120 grit sandpaper. Sand straight along the neck with even
pressure, with the grain of the fingerboard, taking care to follow the
radius of the neck. You will want to sand all the way across the width
of the neck, angling the sanding block to conform to the curvature of
the neck. Take care to stay away from the edges. The are certain to get
sanded as a result of sanding near the edges. Inspect the fingerboard
again and make any necessary repairs.

Method 2:

Fill the fret slots with wood dust by tamping it in with a
business card or single edge razor blade until full. Slowly wick in
super glue until the dust is secured.

Method 3:

Put super glue in the slot and sprinkle on wood dust to set
the glue.

Method 4:

Make a mixture of 5 minute epoxy and wood dust and push into the fret
slots with a business card or razor blade.

Each of these methods requires wood dust lighter than the wood you are
using. The mixture of dust and glue is always much darker than the wood
the dust came from. If you are a perfectionist, and you should be if you
want to be satisfied with your guitar, you should make some tests on
wood dust to glue ratio in order to match the color of your fingerboard.
Compare color of a sanded patch of fingerboard, as some manufacturers
dye their wood, and your fingerboard is probably darker as the result of
use.

****** If you have a light wood fingerboard, I recommend the veneer
method, although recently I was able to do a pretty good match on a
maple fingerboard with acetone-diluted Plastic Wood. It took a lot of
testing,
but it worked pretty well. It does need a top coat of super glue or
urethane, as Plastic Wood is not that flexible.

###########################################################

FRETLESS INSTRUCTIONS

If you are making a fretless guitar, you are almost done. Once you have
the fret slots filled and level sanded, you must sand with increasingly
fine grits. Sand with 220, 320, 400 and 600 grit, then brush off with an
old toothbrush. Inspect the side of the neck and carefully
trim any protruding veneer or glue with a single edge razor bleade or
x-acto knife. If you have been extremely careful, you won't need any
touch-up. Wax the fingerboard, remove the tape and polish the entire
guitar with a soft cloth.

You will need to sand the nut down since the distance between the
strings and the neck is now less by the height of the frets. Mark off a
little less than the height of a fret along the bottom of the nut with a
sharp pencil. Glue a piece of 80 grit sandpaper to a flat piece of wood
and sand the nut by rubbing the bottom of the nut over the sanding
block, sanding almost to the line. Put the strings on and try the
guitar. Play it for a while and adjust the height of the nut until it is
just right.

###########################################################

Calculating the fret positions

Now you have a smooth, filled fingerboard and are ready to mark the
positions for fret slots. To calculate the length of your fret scale,
measure the distance from the nut to the octave fret and multiply by
two. Measuring from the nut to the bridge is not reliable. The general
formula for the distance from the nut to the kth fret is

f(k)=length(1-1/r)

where f(k) is the distance to the kth fret from the
nut, length is the total scale length and r is the ratio you want from
the fret. Let's say, for example, you measured a 12" from the nut to the
12th fret and that you want frets placed so as to give a scale of

1/1, 9/8, 5/4, 4/3, 3/2, 5/3, 15/8, 2/1.

This is an example of a just major scale. The nut
is at 1/1, the first fret is calculated by

f(1)=24(1-1/(9/8))=24(1-8/9)=24(1/9)=2.67",

the second fret is calculated by

f(2)=24(1-1/(5/4))=24(1-4/5)=24(1/5)=4.8".

The remaining calculations are similar. The octave is 2/1, so the fret
calculation is

f(8)=24(1-1/(2/1))=24(1-1/2)=24(1/2)=12",

just as it should be.

The formula for equal tempered fret spacing is the same, but now
instead of ratios, we use powers of two (unless you are using a
non-octave scale).

The formula

f(k)=length(1-1/r)

is better written as

f(k)=length(1-2^(-k/n))

where the carat is the power sign and n is the number of equal tempered
steps to the octave. As an example, let's calculate a few fret
measurements for 19tet with a 35" bass guitar scale. The 0th fret is the
nut, and the distance to the first fret is given by

f(1)=35(1-2^(-1/19))=35(1-.9642)=35(.0358)=1.25".

The distance to the 8th fret is

f(8)=35(1-2^(-8/19))=35(1-.7469)=35(.2531)=8.86".

Keep your figures accurate to four places and your final measurement
should be accurate to 1/100". Notice that .2531 is very close to 1/4.
This is as it should be, since the 8th fret in 19 approximates the
perfect
fourth (4/3) very well, but is a little sharp. Plug 4/3 into the
equation for just frets and you will get

length(1-3/4)=length(1/4)=length(.25).

It is a good idea to test the algorithm a couple of times in this way
before you cut to make sure you are using it correctly.

The general procedure for measuring for fret slots is the same whether
you are using just intonation or equal temperament. Draw a pencil line
down the centerline of the neck. Tape your ruler against this line with
two sided tape with the end exactly against the end of the fretboard,
and make a mark where the first fret will be. Be sure you do
this very precisely. Use a very sharp pencil or a mechanical pencil with
.5mm lead. Mark each fret position until you reach the octave. The last
mark should line up exactly with the former 12th fret. Retape the ruler
at the octave, and mark at 1/2 the distance calculated for the first
octave. Now, depending on the type of ruler you have, either flip it
over and tape it on the other side of the center mark, or slide it over
and tape it parallel to the center mark. In either case you want a new
set of
marks parallel to the first and on the other side of the neck. Repeat
the process until you have two sets of parallel marks. Connect the marks
and you have a set of lines marking where all the frets will be placed.
It is
very important to do the measuring and cutting precisely. Check your
work and redo the process if you have any doubt about the accuracy.

Cutting the new fret slots

It is time to cut the fret slots. If you are cutting the slots by hand,
you will need a guide to clamp or tape on the neck to assure that the
saw cuts the slots accurately. I use a straight piece of wood that has a
little cup cut out so as to fit snug against the face of the
fingerboard. It is possible to cut fret slots by hand without a guide,
but you increase the possibility that the saw will slip and mar the
fingerboard. Tape or clamp the guide to the neck using a leather or cork
jawed clamp, being careful to line it up about 1/2 the width of the fret
saw behind the pencilled in fret mark. Making sure the saw is parallel
to the neck, take one light swipe over the neck from side to side to
make sure the block is properly placed. If the saw has cut out the line
you
are OK. Realign the guide if necessary. Cut into the fingerboard to a
depth of about 1/40th of an inch deeper than the fret tang. You don't
have to be anal about this--you just don't want to cut the slot too deep
or too shallow. The same depth as the old slots is usually about right.
Continue up the neck until you have all the slots cut. You may want to
cut the top fret slots first so that your technique improves as you get
closer to the lower frets, which, in general, will be the most used. If
you nick the fingerboard during this process, wait until after the
position markers are laid in to fix the nicks.

Laying in the position markers

We will now lay in the position markers. Decide where you want the
position dots (if any) and mark them by connecting with pencil the left
and right ends of the fret slots between which the markers will be
placed. You now have an "X" whose center marks the dot's position. Punch
the center and drill the hole to the depth of the marker. Place the
position dot in the hole and wick in super glue. When the dots are set,
sand the fingerboard with the long sanding block using 120, 220, 320
and 400 grit paper until the neck is smooth and blemish free. If there
is any touch up you need to do, now is the time to do it, as once the
frets are laid in this chore will be extremely difficult.

Placing the frets

Re-wax the fingerboard, being careful not to get any in the slots. If
you do, drag the fret saw lightly through the slot a couple times to
remove it. The wax will help keep the super glue leaks from sticking to
the fingerboard. To lay in the frets, cut off a piece of fret wire with
the end nippers (or fret puller or toenail clipper), making sure there
is enough straight tang to span the entire slot. The fret should be a
little longer than the slot so that the deformed end where is was cut
does not have to be pounded into the slot. The protruding ends will be
cut off later with the end nipper. Lay the neck in a padded cradle made
from a 4"x4"x4" piece of wood with a cup cut out about the same radius
as the back of the neck. I use a piece of
sheepskin to line the cradle. This cradle insures that the back of the
neck is protected while the fret is being hammered in and also that
there is a good coupling from the table to the neck to transfer the
energy of the hammer into the fret. For a classical guitar, the cradle
may have to be taller. Plase the fret over the slot and tap the fret in
lightly on one side of the fingerboard using the fret hammer. Once the
fret is seated on one side, tap across the fret to seat it all the way
across. Check to make sure it is seated against the fingerboard by eye
and by trying to run you fingernail under it. If it needs to be tapped
in harder, tap from the center to the outside in both directions. Be
especially careful when doing this on a classical guitar. I prefer not
to fret a classical above the 12th fret using a hammer since the risk of
cracking
the top or loosening braces is so great with this method. If you want to
get fancy, there are a number of products available to press in frets.
Again, you might want to practice on the higher frets first until you
get a hang of the method.

Take the end nipper and start from the lower frets, nipping off the
protruding frets flush with the edge of the fingerboard. With care, you
will not mar the surface. Carefully apply a coat of wax with a Q-tip to
the edge of the fingerboard, avoiding the fret slots. Apply one drop
of super glue at a time to the fret ends, allowing it to wick in. About
3 drops is enough for each side is enough. Make sure glue is not oozing
out the other side of the fret slot. If there are any frets whose ends
just wouldn't stay down when you tapped them in, clamp them down before
you
apply the glue. A little baking soda on the glue will help it set up
faster (though super glue accelerator is better). When the frets are all
glued in, you may find that a little glue has seeped out between the
fret and the fingerboard. Carefully cut the glue off with a single edge
razor blade. You can score the glue next to the fret so it will come off
easily. Here is where the fingerboard waxing is so important. With
enough wax, the glue actually just peels off.

Dressing the frets

Your frets are laid and it is time to dress them. Polish the wax on the
fingerboard until it shines, then lay masking tape between all the frets
to protect the fingerboard. This time, you may need to use painter's
masking tape so it will stick better to the waxed surface. Run a magic
marker across the top of each fret so you can tell what has been cut.
Run the flat file lightly over the surface of the frets along the length
of the neck, taking care to avoid making the same stroke twice. You
should make a sort of criss-cross pattern along the length of the neck,
trying to cover the length of the neck from several different angles.
This way the file will tend to average the height of the frets over the
whole surface.
As you file, the marker is cut from the highest portion of the frets.
You are finished when there is at least a thin line cut through the
magic marker all the way across every fret. Some of the lines of visible
fret material will be wider than others, and that is all right.
Brush off the filings and re-ink the frets. If you have a fret crowning
file, run it across the top of each fret until there is a thin
continuous line of fret material showing.
If you don't have a fret crowning file, run the long sanding block
lightly over the fret surfaces using 320 grit sandpaper until a thin
line of fret material shows through every inked fret. Now is a good time
to lay in side position dots if you want them. The procedure for removal
of the old and laying in the new is the same as that for dots on the
surface of the fingerboard. Use the flat file to smooth the sides of the
fingerboard where the frets end and the dots have been laid in. With
care, you can do this without marring the finish much.
You may want to refinish the fingerboard edges, or you may want to wax
them after a light touchup sanding. Never use silicone wax, as it will
make refinishing impossible should you decide to do so in the future.
With
a jeweler's file or a file with a flat, noncutting edge (place the non
cutting edge in contact with the fingerboard), using one or two light
strokes only, file the tips of the fret at the edge of the fingerboard
where
the fret meets the fingerboard surface. The file should start at 45
degree angles to both the plane of the fingerboad and a parallel to the
length of the fret. The file remains at a 45 degree angle with the plane
of the
fingerboard, but during the stroke its angle relative to the length of
the fret changes from 45 degrees to 90 degrees. This action takes a
little practice, but the end result is a fret with a smooth edge where
the hand is likely to contact it.

To finish the frets, start with 220 paper (or 320 if you used a
crowning file) and vigorously hand sand (no block, fingers gripping a
small piece of sandpaper) each fret along its length to smooth the crown
and remove nicks. When you are done with one grit, move up to the next
finer, taking care to brush the fingerboard free of grit from the
previous coarser sandpaper. This insures that a finer sandpaper will not
drag a piece of detached coarse grit across the fret and mar the
surface. Following the 600 grit paper, use 00 or 000 steel wool for the
final finish. Brush off the neck, remove the tape and admire your
handiwork.

Final steps

Apply a fresh coat of wax or polish, re-attach the neck and replace the
nut. Since you have new frets you may have to adjust the height of the
nut. You can remove material from the bottom of the nut or from the
slots, or if you need to raise the height of the nut (more likely) you
can shim it with slips of brass strip (to be found at hobby stores), or
with drops of super glue on the bottom of the nut hardened and filled by
dropping baking soda on it. File the baking-soda-super-glue filler with
a jeweler's file of an X-acto saw to get the right string height at the
nut. You will probably have to adjust the bridge height too. Open a new
set of strings, string it up and play!!

&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&

Where to get Supplies

A fret saw, fret puller, weighted plastic or brass faced hammer, ruler
marked off in hundredths of an inch, and fretwire can be obtained from
Luthier's Mercantile, Stewart McDonald, GHS, or any number of luthiers's
supply companies. A hand fret saw may be made by purchasing a good
quality miter saw of approximately 0.023" blade width and flattening the
kerf (the waviness of the set of the teeth) carefully with a light
hammer on an anvil or other flat surface.

The ruler in hundredths of an inch can usually be obtained at an art
supply store or sometimes at a college book store (drafting classes!).

Jewelers files can be obtained from jewelry supply stores or good
hardware stores.

Instead of a fret puller, you can grind the face of an end nipper
(availableat a good hardware store) until the bevel of the cutting edges
is ground away and the face is smooth and rounded. I have also heard of
people using toenail
clippers. The main thing is to have a flat or convex clipping face.

--
John Starrett
"We have nothing to fear but the scary stuff."
http://www-math.cudenver.edu/~jstarret/microtone.html

Re: guitar refretting FAQ

🔗John Starrett <jstarret@carbon.cudenver.edu>

🔗John Starrett <jstarret@carbon.cudenver.edu>