U.S. Guitar Kits Acoustic Guitar Kit User manual

Copyright © 2010 by U.S. Guitar Kits, Inc. All rights reserve .
U.S. Guitar Kits, Inc.
Assembly Instructions for Acoustic Guitar Kit
Welcome
Thank you for purchasing the kit. All the guitar components needed to build
your guitar are included to build a fine instrument. ou will need glue,
finish, a variety of ordinary woodworking tools and average woodworking
skills. Knowledge of the use and sharpening of scrapers is crucial and
included is a set of instructions for this tool from a tool supplier.
Please note that although we warrant this kit to be free from defects in
materials and workmanship for 30 days from purchase, we cannot guarantee
the outcome of your instrument since skill levels vary greatly. If you take
your time and follow these instructions precisely and in the order in which
they are presented you will be rewarded with an instrument of which you
can be proud for a lifetime. Take your time, work carefully. Please keep
your kit sealed until ready to use to avoid problems due to moisture and
humidity. We will not replace parts that have been affected by moisture.
Always use safe methods while working and employ all safeguards
including safety glasses and other personal safety devices.

2
2
Tools, Jigs and Materials
- 25-30 Spool Clamps;
- Small router or laminate trimmer;
- a rabbeting bit set that includes the following cuts;
1) 1” Cutting Diameter Bit
2) .88” Bearing-Binding Cut
3) .48 – Six Pieces of Purfling
4) .64 – Five Pieces of Purfling
5) .70 – Four Pieces of Purfling
The set is available from www.usguitarkits.com or available as
separate items.
Determine the number of purfling strips to be used and select the
appropriate bearing (.48, .64 or .70).
The .88” is used for the thicker binding strip on both the top and
back.
- a ½” diameter or smaller flush trim router bit. Ball bearing pilot is
strongly recommended;
- 1 F-style clamp;
- A STRAIGHT straightedge at least 18” long;
- a selection of small flat chisels- ¼” and ½” are required, 1/8” chisel
and others are nice to have;
- flat scrapers
- a utility knife AND an Exacto® type knife;
- #1 & #2 phillips screwdrivers and a 10mm deep socket with handle or
equivalent open end wrench;
- a shot filled hammer with plastic or brass heads (or both);
- a tapered reamer (plumbers reamer) 3 & 5 degree or one 1/8” to ½”
- a selection of drill bits including 3/8”, .065”/1.7mm, .182”/4.6mm,
.056”/1.4mm;
- a roll of blue painters tape (or other strong tape that does not leave a
residue) OR some (25 to 30) big fat rubber bands measuring at least
16” to 24” long when stretched;
- choice of aliphatic resin (Titebond) or liquid hide glue;
- bottle of slow setting gel cyanoacrylate glue and a bottle of
accelerator, de-bonder recommended to un-stick fingers;
- tube of Duco® cement or similar clear plastic-to-wood glue;
- acetone;
- some scrap wood blocks of varying sizes;
- a 20” radius sanding block including 80, 120 & 220 grit adhesive
backed sandpaper;

3
3
- 400, 600, 1000, 1500 grit sponge sanding pads, higher grit micro-
mesh pads are optional depending on the desired sheen of the
fingerboard;
- a fret crowning file;
- a small triangular file;
- a bastard mill file;
- a good wipe-on gel finish. Avoid stain and oil finishes and give
preference to hard finishes such as lacquer or urethane. Avoid
Minwax® (sorry).
A final word before you start- It is highly recommended that you read ALL
of the assembly instructions first, then go back and start assembly. Although
it may not make sense to you be sure to follow the instructions in precise
sequence or you may have to disassemble parts or even start over.
Also, be sure to read and understand the use and care of all tools and wear
the proper safety equipment including but not limited to safety glasses,
hearing protection and all guards that are part of the equipment used.
It is important to note that this is a fine project that takes time and very
precise measurement. e sure to take your time on each step and ALWAYS
be safe using the tools during your woodworking projects. Also, be in the
right frame of mind where your mind is clear and not distracted. Stay
focused and you’ll be more likely to remain safe and end up with a nice
guitar.
Good Luck!

4
4
Guitar Terms & Anatomy
The guitar is made up of several components. The following list is a list of
those components that can be cross referenced to the diagram for easy
identification.
Not illustrated are:
1) Frets-Hammered/Pressed into the Fingerboard
2) Abalone Dots & 12
th
Position Marker-Glue into the Fingerboard
3) Kerfed Lining-Pre-glued to inside of soundbox where the sides meet the
top & back
4) Bracing-Pre-glued to top & back
5) Binding & Purfling-Glued to the perimeter of top & back where it meets
the sides

5
5
Main Objective:
Preparing the top for glue up. Glue top and allow 2 hours of clamping time
and prepare all small parts for assembly.
Step One- reparing the Top
The top is pre-braced and you will begin by marking and cutting bracing and
then thinning out the bracing on the ends to fit into the kerfed lining on the
sides of the guitar.
Note: Identifying the braces. See picture.
Note: The bracing on the top consists of the
Shoulder Brace, an X-Brace, 2 Tone Bars and
2 small Finger Braces as well as a Bridge
Plate.
It is important to note that the only braces that
touch the lining are the shoulder brace and X-
braces. All the others are scalloped flush to
the back of the top and cut short of the sides.
1) HEADS-U -Remove the shipping stretcher at this time. The
stretcher is the wooden piece running through the length of the guitar
connecting the end block to the neck block. This is used for shipping
purposes only and to make a simple stretching jig (next step).
2) Using a flexible tape measure, measure the distance between the
kerfed lining on the back at the widest part of the guitar.
3) Using the wooden shipping
stretcher, take the previous
measurement and add ¼” (equal to
the kerfed lining on both sides).
4) Cut the stretcher to that length.
a. This length should be pretty
close to 15 ¼”. It’s always
easier to cut it a bit longer
and then have to shorten it.
b. Slightly round both ends.

6
6
5) Cut the stretcher almost all the way through, put a shim in the kerf cut
and re-tape it back together using blue tape. This is done so that once
the top is glued on, the tape can be removed and the stretcher can be
broken and removed through the sound hole. Otherwise, the stretcher
could become lodged and difficult to remove.
6) Slowly and gently spread the sides to install the stretcher below where
the top will install by approximately 1”. If it sits to close to the top,
the stretcher will interfere with the braces of the top.
7) Sight down the sides of the guitar to ensure the
sides do not appear to be bowed inward. ou
should be dead on. If not, modify the length of the
stretcher either longer or shorter to correct any bow
in of the sides.
8) Once the stretcher is in place and the sides are
“true”, leave it in place during the entire process all
the way through the glue up of the top.
9) Mark the centerline of the top with a pencil on both
the top and back side of the top for easy
identification through the following steps.
10) Place the top face down with the braces
facing up.
11) Place the soundbox centered over the top
with the top (“shoulder”) brace contacting the neck
plate initially and then pulling back slightly (1/16”) so there is no
contact that could potentially cause a “rattle”.
12) Being careful not to move either the top or the body, mark the
bracing where it will touch the lining by running a pencil flush with
the outside of the sides. Be sure not to move, bend or distort the
soundbox while marking.

7
7
13) Looking at the space between the
top and soundbox, mark the sides
where the “X & shoulder” bracing
contacts the soundbox. Two marks for
each brace. Ie Left & Right. We will
revisit these marks in Step 2-1.
14) Make a solid mark on the back of
the top 3/16” larger than the sides. Do
this by holding a sharp pencil on the
side of the guitar and allowing the point
to mark the back of the top. This will be
the trim line to remove the excess wood
before clamping with glue.
15) Remark the ends of the x-braces
and the shoulder braces inward by the
thickness of the sides only, not
including the kerfing.
16)
Note: The initial mark on these braces
reflects the outside of the guitar body.
Note: The brace will fit into a pocket we will
cut later in the kerfing.
17) The tone braces and finger
braces are remarked and cut so that they will not be touching the
kerfing.
18) Locate the top and put the top face down on a clean non slip
surface. Remove the soundbox and cut the bracing off flush with the
back of the top. Be careful not to
make divets in the back of the top.
ou will need to chisel the small
pieces off being careful NOT to pry
and risk cracking the top or separating
the brace from the top. Once
removed, lightly scrape the surface
where the brace was glued to ensure a
clean surface to glue the top to the sides.

8
8
19) Mark the ends of bracing that will touch the side kerfing 3/16”
thick or simply lay a sharp pencil flat on the back and mark the ends
of the bracing.
20) Scallop the end of the bracing to the 3/16” mark.
21) The shoulder brace can be left thick as this does not
dramatically change the overall sound. Using a sharp chisel, follow
the existing curve of the brace and reshape the end to be 3/16” thick.
Note: Be sure to review pages 9-11 for tips and information on scalloping
the braces.
Note: When you are using a chisel and creating constant downward
pressure to thin your bracing, be sure to rest the top on a hard surface. If
you use a spongy non-skid pad to rest the top on, you risk significant flex
and possible damage to the top. Be careful…be gentle!!
Alternative to Step 19-21: Using a small laminate router, cantilever it
over the workbench on a piece of 1” scrap and use a ½” straight cutter set
at a height that will cut the brace to 3/16” high. (Be sure to cut a test
piece.) With the top face down, pass the ends of the x-braces and
shoulder brace under the cutter to trim the ends. Now scallop the braces
to the new height of the ends of the braces. This method will ensure a
uniform height for all the braces. A Dremel tool with a base and a small
straight cutter could be used to trim the lining, being careful not to cut all
the way through the sides of the guitar. See the attached photo.
22) Use the trim line from Step 7 to cut and remove the excess top
using a sharp saw, preferably a bandsaw.

9
9
Scalloping the ends of the Tone Braces
Cut the end of the tone brace.
Note: The ends of the tone
braces do not touch the sides of the
guitar.
Mark the brace for scalloping.
Note: Mark the trim line
approximately 1/8” back from the
existing curve and follow the same
curve.
Scalloping the end of the tone brace.
Note: The end thickness should
be around 3/32”.
The final shaping of the tone brace.
Note: Use a chisel to round off the
edges and final smooth with 120 grit
sandpaper.

10
10
Marking and Scalloping a Tone Brace

11
11
Bevel the sides of the braces
and final smooth with 120 grit
sandpaper.
The Finger Brace
The final shaping of a finger brace.
Note: The end of the finger
brace can be scalloped almost flush
with the top.
Scalloping the Braces
The previous several photos are used to illustrate the methods used to trim
away the heaviness of the braces to allow for better top vibration which
produces better tone and volume.
This is a detailed science for the professional luthiers and there are many
schools of thought.
Provided in the instructions are simple cutouts that can be placed beside the
braces for marking that will provide good sound results.

12
12
Finger Brace
Lower X-Brace
Tone Brace
Upper X-Brace
Brace Templates
Cut out and lay
on side of braces
to mark

13
13
Step Two- reparing the Sides for the Top
The sides have lining already attached around the inside perimeter of the
body of the soundbox. Lining provides a larger gluing surface for the top to
attach. Each brace needs to be le tt t into the lining by cutting small pockets for
the bracing to rest on.
1) From step 1-13. Looking at the space
between the top and soundbox, mark
the sides where the “X & shoulder”
bracing contacts the soundbox. Two
marks for each brace. Ie Left & Right.
We will revisit these marks in Step 2-1.
2) Transfer the marks along the top of the
lining, connecting the diagonals of the
X-brace and the shoulder brace.
3) Mark the depth of each pocket equal to the ends of the braces. Ie
3/16”. Now, VER carefully, start to cut away the lining at each mark
with a chisel or utility knife until the top fits flush onto the soundbox.

14
14
4) Continue to dry fit the top until it
lays completely flush with the sides
with even pressure all the way around.
Note: Many makers like to sign their guitars. If you plan on autographing
the guitar, now is the time.
Step Three-Gluing the Top
1) Final dry fit the top to the sides making sure the top fits nicely.
2) Apply glue around the entire perimeter of the soundbox on the lining
and on the neck and end blocks. Be very careful, sloppy glue joints
inside a guitar are a sure sign of careless workmanship. Do not apply
glue to the top!
3) Install the top, check all your alignments again, making sure the ends
of the braces are seating in their pockets.
Note: The main objective in gluing the top is to
ensure the top of the neck plate is completely in
contact with the bottom side of the top.
4) Place a clamping caul on the top directly over
the shoulder brace. Clamp, through the soundhole
using an f-style or c-clamp, the neck plate and the
clamping caul. Be sure to site in the neck cavity
for a flush fit between the top of the neck plate and
the bottom side of the top. Scrape any excess glue
overflow in the neck pocket with a 1/8” chisel.
5) Inspect as best you can to insure the top is
firmly fixed onto the soundbox. If you see gaps,
use a little more clamping pressure.

15
15
6) Using approximately 25-30 spools
clamps, continue clamping about ¾” apart.
7) Set the assembly aside until the glue
sets. With aliphatic resin (white or yellow
glue) this means about 1 hour, preferably 2
hours.
8) Remove clamps.
Note: Make sure the clamping pressure is
over the sides and not over the middle or
way over the sides as this will crack the
top and likely create irreversible damage.
Note: We suggest spool clamps that can be
hand tightened with medium, even pressure. Over tightening clamps is
unnecessary and creates unneeded stresses.
So far….so good!
ou have now completed all the steps to complete the top installation.
Student Notes:

16
16
Miscellaneous arts reparation: There are several small parts that need
to be prepared for assembly and can be worked on in no particular order.
1) Using a tapered reamer slowly remove enough material to make the
machines a press fit. Note: Backside of the headstock only!!
OR
Using a 3/8” non-brad point drill bit, drill 3/8” deep holes (DO NOT
DRILL ALL THE WAY THROUGH!) on the backside of the
headstock, following the existing holes.
Note: Use a drill press to control the depth of cut.
Tip: Drill a scrap block to determine depth so that machine sits flush
in hole.
IM ORTANT NOTE: DO NOT DRILL HOLES ALL THE WA
THROUGH THE FACE OF THE HEADSTOCK.
2) Truss rod fitting-Make sure the truss rod’s flat surface is face up and
lay just below flush with the top of the neck. The truss rod should fit
without having to jam it in, at the same time, it should not be loose.
3) Sand bridge-Sand the back of the bridge to remove any machine
marks and clean the surface with acetone (just before glue up) to
remove any oils and create good adhesion for the glue. Break the
edges on the rest of the surfaces.
4) Sand the Fingerboard-Sand only the back of the fingerboard to
remove any machine marks being careful not to remove any more
material than necessary. Also, sand evenly being careful not to sand a
twist in the fingerboard. Clean this surface with acetone (just before
glue up) to remove any oils and create good adhesion for the glue.
Student Notes:

17
17
Main Objective
Cut notch in top for neck tang. Set the neck angle. Prepare and
glue the fingerboard to the neck. Cut groove for binding and glue
top and back binding.
Step Four- Cutting the notch in the top for the neck tang.
Set up a small laminate router with a small bottom bearing flush trimming
router bit and follow the groove of the neck tang. Be careful at the end to
ensure you do not create a tear out at the end of the cut.
Flush trim approximately 1” on each side of the neck pocket, where the neck
will touch the body.
Note: The cutter depth should be set up so that the bottom of the cutter is
flush or just below the thickness of the top.
Note: If you do not have a bottom bearing flush trim router bit that will
work, use a straight cutter and “freehand” the cut, staying clear of the sides
of the neck plate mortise. Finish trim the sides of the mortise using a chisel.
Step Five- reparing the Neck
The neck is an important step in fitting to the body before the fingerboard
is attached. Extra time here will ensure a tight fit between the back of the
fingerboard and the top in final assembly, as well as having good
playability.
The tang is separate from the neck at this point. Go ahead and hold the
neck heel flat against the
body of the guitar and hold
a straightedge on top of
the neck to span the body.
The goal is to have the
neck “in plane” referring
to a straight line running
on top of the neck and the
top, to the rough location
of the bridge.

18
18
Next, you should place the fingerboard on top of the neck and the bridge
in its rough location. Place the straight edge on top of the neck and
project the out to the bridge. The straight edge should be above the
height of the bridge between 1/32” and 1/16”.
See below for details to correct “Pitch Back or
Pitch Forward”. If sanding is needed, a light
touch and careful attention not to sand a twist
into the neck. Continue to check progress by
attaching the neck and placing a straight edge
over the neck and check for “flat” across the top.
If needed, bolt the neck on using the two long
neck bolts.
IM ORTANT NOTE: Mark the top of the neck at the two sides where
the tang will be inserted. Make that mark 1/8” back on both sides. These
are “witness” marks that are guides that will keep you from sanding one
side more than the other.
DISC SANDER INSTRUCTIONS - CORRECTING NECK ANGLE
If you have a disc sander, the below instructions will provide steps to
quickly correct the neck angle. The machine setup here is critical to the
outcome and improper setup and subsequent sanding could result in an
undesirable and irreversible result. Check and double check.
Make some markings on the face to
be sanded and two marks at the top
of the neck.
Push the neck heel face flat on the
sander disk face (without it on) and
then push the mitre gauge (loose at
this point) up against the side of the
neck....tighten the angle knob.
This will ensure you will sand the
correct angle left to right and not
sand a skew.
Set the angle of the table (small
increments) and sand a quick
witness mark to be sure you
sanding evenly on the neck heel
face.

19
19
IM ORTANT NOTE: Be sure to initially touch the neck to the heel
surface and check that the sanding mark is not just on one side. This will
cause the neck to sit skewed on the body of the guitar.
If the neck is sitting to far back, an adjustment of the table so that the
heel closest to the top of the neck is pretty much the only thing being
sanded and the bottom of the heel barely gets touched.
Once the bottom of the heel comes in contact with the disk
face....STOP...you're there.….re-fit
itch Back
If your neck is pitched back and there is a large gap above the bridge and
below the straightedge, the neck heel needs to be sanded more at the top
of the neck and feathered in to the bottom of the neck heel (little if any
off the neck heel). This will allow the neck to rotate forward.
BE SURE TO SAND FLAT AND EVENL ! When you dry fit the neck,
it should NOT rock in the middle of the neck heel…you have hump in
the middle….flatten out the middle…..re-fit.
itch Forward
If your neck is pitched forward and the straight edge hits below the
height of the bridge, the neck needs to be sanded more at the bottom of
the neck heel (and little if any off the top of the neck heel.) Make a mark
1/16” back on the neck heel face. Use that line as a reference to sand
back to.
BE SURE TO SAND FLAT AND EVENL ! When you dry fit the neck,
it should NOT rock in the middle of the neck heel…you have hump in
the middle….flatten out the middle…..re-fit.
Neck Bolt Tip
ou may need to open the holes on the body where the neck bolts go
through. Do not use a bigger drill bit as that could oversize the hole too
much. Use a small file to elongate the hole either up or down depending
on whether the neck needs to shift up or down a little bit.
As a final test, bolt the neck on and dry fit the fingerboard and bridge.
Using the straightedge laid on top of the fingerboard, project that line to
the bridge which should be at the same height or just above (between
1/32” and 1/16”). Continue to make adjustments to get within this
tolerance.

20
20
The fingerboard should be able to lie flat on the top of the neck and the
top without any gap under the fingerboard. If there is a gap, the pocket
may need to be lowered. See High Tang/In lane – Next page.
Insert Neck Tang
Once the neck is “in plane” glue in the neck tang. Be sure it clamps flat
and does not “creep” out while gluing.
“Creep” is when a glue joint moves during the gluing and clamping
process. It is important to have straight downward clamping pressure and
not clamping at an angle. Angled clamping pressure can often slowly pull
pieces away from each other during a glue up.
NOTE: ou may find that if you change the neck
angle, the neck tang may be too long and push the
neck away from the body (shown in picture). Simply
shorten the length of the neck tang on the end that fits
into the neck. Be sure to sand this evenly so that the
tang fits nicely into the neck pocket.
Note: ou will also need to be sure the bottom of the tang mortise is at
the same height as the mortise in the body. If they are not equal, set up a
router with a straight bit and freehand the groove staying away from the
sides of the mortise. Clean up cut with a chisel. Typically, the body
mortise would need to be lowered by a very small amount….1/32” to
1/16”.
Test Fitting
Once you have everything where you like it, bolt it all
together in a dry fit and sand the top of the neck tang
flush with the top.
Important Neck Angle Troubleshooting & Support
As each kit may vary slightly, it is important to get the neck in “plane”
with the top. If this step is rushed without careful attention to detail, setup
for good playability in the later steps will be very difficult to correct at
that time.
If you encounter an issue that you are not comfortable troubleshooting,
please e-mail us a digital picture to [email protected]om with a
description and we will contact you immediately to get you back on
track. Our goal is to ensure 100% customer satisfaction.