Construction Notes for a Classical Guitar - sample

CONSTRUCTION NOTES for a

CLASSICAL GUITAR

by

Denny Brown Foreword by Robert O’Brien

Print this page, cut out the label and place in a binder spine

Cover: Double Top Classical Guitar by Denny Brown Photo credit: Jodi Jack, used by permission © Dennistoun Brown 2012

2

CLASSICAL GUITAR

Binder Spine Label

Construction Notes for a Classical

Preface

Preface

Construction Notes for a Classical Guitar is a conversion of my notes into detailed building instructions for a 650 mm scale length classical guitar. Like its companion, Construction Notes for a Steel String Guitar, it is based on study under Robert O’Brien ,while he directed at the Red Rocks Community College Lutherie Program in Denver, Colorado. The original audience was students in Robert’s classes. However, with the release of his “Online Classical Guitar Building Course” in 2011, the first version was rewritten for the benefit of online students, as well. Greatest credit for this handbook goes to Robert O’Brien, who in 2003 founded and, until 2012, directed the Lutherie Program at Red Rocks Community College in Denver, CO. This is primarily a tabulation of his teachings. Other information in Construction Notes for a Classical Guitar comes from a variety of sources. Fellow teaching assistants, Gregoire Fulgham and Mike Peter, were most helpful. Their guidance was towards the right way and, perhaps, more importantly, away from the wrong. Many of their tips are found in this handbook. The rest, which really doesn’t seem to leave much, I learned on my own through a combination of technical successes, a few “design opportunities,” i.e. mistakes, and outside reading. Robert O’Brien, to date, has supervised the building of over 500 guitars by students in Colorado, from teenagers to retirees. Several of his students relocated to Colorado specifically to take one or more of his courses. Robert’s commitment to teaching is known internationally. The DVDs that Robert made for his early students have guided thousands of guitar builders who purchased guitar kits from LMI, Int’l. More recently, Robert’s “Online Classical Guitar Building Course” and “Online Acoustic Guitar Building Course” were released, which display his ability to distill the complexities and mysteries of guitar making into logical steps. Besides his personal and professional commitments, Robert finds the time to host and actively participate in a Google Chat Group on guitar building. Participants hail from the U.S., Canada, Europe, South America, Australia and Asia. You are invited to join his group at www.groups.google.com/group/obrien-forum.

Construction Notes for a Classical Guitar

Preface

None of this is to say that Robert has made guitar making easy. It is not, and it probably never will be. However, he has given many people worldwide the confidence to take the risk to do what for them had only been a dream. Happy building! Denny Brown Boulder, CO

4


Introduction

Introduction

While these notes are based on several sources, they distill down to one of many ways to build a classical guitar. Indeed, every luthier has his or her own method to make a guitar. With so many steps, variations quickly develop. Nonetheless, what I have recorded closely follows the current methods used by Robert O'Brien. Experienced builders can use Construction Notes for a Classical Guitar alone as a reference to refresh his or her memory on the steps of building, or to see another way to do things. For the first-time guitar maker, this handbook alone is probably inadequate as a guide to building a classical guitar. Some things just have to be seen once or twice before they make sense. The materials and dimensions used in this handbook are based on the LMI (Luthiers Mercantile, Int’l ) KLCRO kit, used in Robert’s classes and in his online course. However, this does not preclude the use of materials from numerous other quality luthier sources. Construction Notes for a Classical Guitar can also be paired with Robert’s DVDs and his free YouTube “Luthier Tips du Jour” series. Several books and videos are available from other reputable authors. However, all of these resources differ to some degree from this handbook. In the case of Robert’s DVDs, certain sections are dated. When there is a disagreement between the DVD and these notes, methods here are most current. For convenience, hyperlinks are provided throughout the text to “Luthier Tips du Jour” episodes and to each “Online Classical Guitar Building Course” lesson. The Table of Contents also links to respective sections in the handbook. The best learning experience, of course, is to build your guitar with Robert O’Brien in Colorado. For those who cannot, his "Online Classical Guitar Building Course” is a remarkably close second best option. It is every bit as detailed as his classes, perhaps more so.


Introduction

You may print this manual. Use it to take notes. Lots of notes. The true discovery of great things in your guitar will happen over 215 pages from here when you first put on the strings. No sooner. If your guitar is a home run, wouldn’t you like to have some clues how it happened? On the other hand, if your guitar doesn’t come out the way you wanted, wouldn’t you also want to know why? Take notes. When you are ready to build a steel string guitar, be sure to take a look at Robert O’Brien’s “Online Acoustic Guitar Building Course”, and the companion handbook, Construction Notes for a Steel String Type to enter text Guitar. Input for Construction Guitar is welcome.

Notes for a Classical Write to me at

[email protected].

A word of caution Several steps of building a guitar are dangerous, including those using hand tools. It is the reader’s responsibility to learn how to use and maintain equipment safely and correctly.

This is not a safety manual.

6


Foreword

Foreword

Denny Brown’s Construction Notes series for guitar building is the set of books I had planned to write for my students, but somehow I never got around to actually doing it. With a young family and a growing lutherie program, this task never managed to move to the top of my “To Do” list. I was thrilled when Denny unexpectedly presented his first book on the classical guitar to me in December of 2011. I immediately asked to use it in my classroom and hoped he would write a steel string version, too. (He did.) Actually, I think that I was not only thrilled, but relieved that this long overdue project was finally complete. Denny went above and beyond what I had envisioned and created an interactive manual. Students have instant access to my online courses and Luthier Tips du Jour videos just by clicking on the active links throughout the text. Since Denny introduced these texts, my students’ work has improved significantly. Students now have a written study guide that allows them to prepare for class ahead of time. In the shop, they have a detailed checklist to minimize mistakes. And as importantly, they have a place to record notes on their progress. As an instructor, these books have made my life easier and helped my students build better guitars. Denny has meticulously captured how I build guitars. He also offers some additional perspective, which is a bonus for the user. These handbooks have become an indispensable part of my teaching and are now required reading for students in my workshop. Using these books will make your guitar-building experience more rewarding and easier than ever, leading to the result you want: a guitar that both looks and sounds beautiful. Robert O’Brien Parker, Colorado www.obrienguitars.com


About the Author

About the Author

Denny Brown discovered fine woodworking in 2007 after retiring from a career as a general surgeon. He found one of the premier woodworking programs in the United States just forty-five minutes from home. His passion for fine craftsmanship and detail led him to Robert O’Brien’s guitar-making classes. Denny builds both steel string and classical guitars. He is a teaching assistant for O’Brien’s guitar building classes in Denver, Colorado. He is also the author of Construction Notes for a Steel String Guitar. Denny lives in Boulder, Colorado with his wife and children.


Table of Contents

Table of Contents

Chapter 1: Neck

11

Cut the Scarf Joint ...................................................................................11 Layout

11

Clean Up the Scarf Joint

13

Laminating the Neck

13

Calculate the Peghead Thickness

13

Scale Layout

14

Glue Up

15

Glue the Scarf Joint

16

Thickness the Peghead ............................................................................17 Thicknessing the Peghead

17

Scale Layout ...........................................................................................18 Mark the Scale Length

18

Neck Thicknessing Setup - For a Short Neck

19

Thickness the Neck

20

Peghead Veneers .....................................................................................21


Table of Contents

Attach the Heel Block ............................................................................22 Cut the Veneer Overhang ......................................................................23 Cut the Heel Slots at the 12th Fret ..........................................................25 Veneer the Back of the Peghead ............................................................26 Peghead Shaping and Tuner Holes .........................................................27 Shape the Peghead

27

Drill the Tuner Holes

28

Cut the Tuner Slots

29

Cut the Top Relief ..................................................................................30 Shape the Heel ........................................................................................31 Shape the Front of the Heel

31

Shape the Sides of the Heel

31

Finish Shaping the Heel Block

31

Cut the Heel to Height

32

Taper the Neck .......................................................................................32 Seal the Heel Block ................................................................................32 Carve the Peghead Slots ........................................................................32

10


Chapter 1: Neck

Chapter 1: Neck •

See “Online Classical Guitar Building Course”: o Sample Lesson Excerpts (free) o The LMI Kit (free) o Controlling Relative Humidity(free)

Cut the Scarf Joint • •

See “Online Classical Guitar Building Course”: The Scarf Joint See “Luthier Tips du Jour”: o Neck Blanks o The “V” Joint o Bandsaws

Layout •

Neck wood considerations o Tap the neck blank §

§ § § §

Hold the neck blank at the node, about 2.5 - 4.5 cm in from the

side and the end of the board, along the left or right side • A node is a point where the vibrations of the wood cancel out • By holding at the node, the impact on the board’s tone when struck is minimized Tap the board with a knuckle Adjust the holding point until a nice ping is heard Tap it on a concrete floor to listen for cracks File these tones away mentally • The meaning of the sound will come with experience

11


Chapter 1: Neck

o If any milling is done, be very careful not to get the blank too thin

(22mm limit) or too narrow for the peghead design

Check the width tolerance using the peghead template (see Shape the Peghead, below) o If there is grain runout towards one face at the end of the board, select that one to be the top face of the peghead o If only one side is square, orient that side down for the band saw cut §

•

Mark for cutting the scarf joint o In Robert’s videos, he marks the scarf joint in a different fashion than shown here, but the end result is virtually the same o On the side of the blank, mark 125 mm in from the end

o Use a protractor and draw a 12-15o line from top left to bottom right § Left handers may want to draw the line from the bottom left to top right for an easier position in the band saw ⇊ Top face side of Peghead ⇊

Cut Line

⇊ Neck Piece ⇊

125 mm

⇈ Peghead Piece ⇈

•

12

12-15o angle

Cut the line with a band or hand saw o The short piece is the peghead, the long piece is the neck


Chapter 1: Neck

Clean Up the Scarf Joint • •

See “Online Classical Guitar Building Course”: Cleaning Up the Scarf Joint See “Luthier Tips du Jour”: o Sharpening o Hand Planes

• •

Square a line across the peghead piece at or next to the angled cut True up the cut surface to the squared line with a block plane o Clamp in a bench vise o Or clamp the peghead on top of the neck blank with the peghead slightly overhanging the cut surface of the neck o Judge flatness using a straightedge on the planed surface Fine tune with a sanding block or sandpaper on granite Use a belt sander with caution, i.e. don’t Test the joint

• • •

o Roll the peghead 180o to join its cut surface to the back flat surface of the neck o Check both sides for tight fit and adjust § This is critical o True the neck surface, if needed, usually just block sanding o

Laminating the Neck • • • •

This is an optional, but really good looking step, that puts a strip of accenting wood down the center of the neck It is not covered in the: “Online Classical Guitar Building Course”, but is covered in the Neck section of the “Online Acoustic Guitar Building Course” If you don’t want to do this step, skip ahead to Glue the Scarf Joint The portion of the neck blank that will become the heel needs to be cut off before laminating the neck o This requires a few steps to calculate that length

Calculate the Peghead Thickness •

Position the peghead piece against the back of the neck where it will be glued 13

Construction Notes for a Classical Guitar •

Chapter 1: Neck

The final thickness with veneers will be 22 mm or the actual tuner height o Measure the tuner height if there is any question

•

Measure the peghead veneer thickness with calipers (usual 4 mm) and subtract

this from 22 mm to get the thickness of the peghead before veneers are applied o Example: 22 mm (final thickness) - 4 mm (typical veneer thickness) =

18 mm (working thickness) §

•

Final thickness - veneers = 22 mm - _____ mm = _____ mm

o Mark off a thickness of 18 mm, or the calculated thickness needed, if it is different, on all three sides of the peghead § Measure from the back of the peghead o Connect these dots, run the line to the top surface of the neck and mark that point § This is the nut reference point Set the peghead piece aside

Scale Layout •

Starting at the nut, mark at these locations along the side of the neck o 0 mm = nut/peghead junction

o Add 5 mm = nut/fingerboard joint o Add 325 mm = 12th fret

o Add 35 mm = heel block

o This should total about 365 mm o Measure the remaining piece of the neck blank §

It should be about 270 - 280 mm long •

If it is anything more, especially in the 295 - 315 mm range,

STOP!

o Make sure the heel block measurement was added after the 12th fret

o Cut off the extra piece § This is the heel piece § Smooth both faces of the cutoff by jointing or planing 14

Construction Notes for a Classical Guitar §

Chapter 1: Neck

Mark it for orientation (top, left, right), and set it aside

Glue Up • •

•

Select a piece or pieces of wood at least 25 mm tall and long enough for the whole neck piece Rip the neck down the center on a table saw o Plane or lightly joint the sawed surfaces Glue up o Apply glue to the layers § This will be messy o Alignment is very important so minimal thicknessing is required o Clamp time 120 minutes

•

Scrape off the glue

•

Plane or joint the faces and sides o Hand plane or joint/planer the top and back faces flat § Use thin cuts on jointer/planer § If using a hand plane, make sure the two faces remain parallel o The neck is now wider than the peghead § The widths need to be the same § Use a jointer or a hand plane • Make an equal number of passes on both sides and compare widths with the peghead piece o The laminated wood will be the centerline reference, so keep it in the middle • Repeat until the two are the same width • Stay square with the top face

•

Cut off the laminate at the scarf joint o A portion of the laminate will protrude at the scarf joint o Cut this off with a saw o Plane flush 15


Chapter 1: Neck

Glue the Scarf Joint •

See “Online Classical Guitar Building Course”: Gluing the Scarf Joint

• •

Work on a flat surface Assemble tools o Cauls for top and back of the peghead, no taller than the neck is wide o Stop blocks for each end of the neck o Clamps § 2 Cam clamps for the neck § 6 C-clamps for the glue joint Glue up o Do dry run o Lay down wax paper under the joint o Line up the peghead and neck laid on their sides o Clamp the neck to the bench with a cam clamp § Check that the neck is square to the bench § Shim if needed o Clamp stop blocks firmly at each end of the neck and peghead to prevent slippage when clamps are applied to the joint

•

§

o o o o

o

16

Set the blocks so neck overhangs the peghead 2-3 mm after the

clamps are on • The two pieces will push away from each other when Cclamps are applied, so position the stop blocks to leave a larger overhang Apply glue to the peghead, “Less is more” § Too much glue will make it slip more Align the peghead and neck between the stop blocks Pinch the pieces together and use a cam clamp over the top of the joint to clamp it to the bench Add cauls and only lightly apply clamps, two on each side § Watch for slip and keep track of the overhang § Adjust stop blocks if needed to keep an overhang Once the pieces are in place with light clamping, wait a few minutes for the glue to tack up, then tighten down the clamps firmly


Chapter 1: Neck

o Remove the neck from the bench and the check the other side of the joint o Clean glue squeeze out o Clamp time 30-45 minutes o Scrape off any excess glue o Plane the joint flat along the sides, if needed, but be careful not to narrow the peghead width § Use the peghead template to be sure of the fit o If the joint is gapped or slipped badly, simply recut the joint, and start over at Clean Up the Scarf Joint

Thickness the Peghead Thicknessing the Peghead •

See “Online Classical Guitar Building Course”: Thicknessing the Peghead

•

The final thickness with veneers will be 22 mm or the actual tuner height o Measure the tuner height if there is any question

•

Measure the peghead veneer thickness with calipers (usual 4 mm) and subtract

this from 22 mm to get the thickness of the peghead before veneers are applied o Example: 22 mm (final thickness) - 4 mm (typical veneer thickness) =

18 mm (working thickness) §

Final thickness - veneers = 22 mm - _____ mm = _____ mm •

If planning to veneer the back of the peghead, remember to add that thickness to the veneers stack

o Mark off a thickness of 18 mm, or the calculated thickness needed, if it is different, on all three sides of the peghead all the way back to the top of the neck o §

Measure from the back of the peghead 17


Chapter 1: Neck

o Square a line across the angle of the peghead to join the lines o Partially remove the excess peghead with a band saw,

§ Leave a 2-3 mm margin o Finish thicknessing the peghead with a large hand plane § Monitor the reference lines and use a dial caliper to measure thickness as you go • It is easy to get too thin towards the end of the peghead § Check for flatness and square • Watch the squared line • Also, watch the seam of the joint • It, too, will be square when the thickness on the left and right are the same § §

If the square line disappears, redraw another one right behind the last one o Finish with a sanding block o The neck angle line needs to be crisp and square

Scale Layout •

See “Online Classical Guitar Building Course”: Scale Layout

Mark the Scale Length •

Mark at these locations along the side of the neck (repeat this if the neck was laminated) o 0 mm = nut/peghead junction

o Add 5 mm = nut/fingerboard joint o Add 325 mm =12th fret

o Add 35 mm = heel block

o This should total 365 mm o Laminated neck:

18

Construction Notes for a Classical Guitar § §

Chapter 1: Neck

If the total length just measured comes up short, skip forward to Neck Thicknessing Setup If these measurements leave you with enough or excess neck, skip forward to Peghead Veneers

o Non-laminated Neck: § The remaining piece is for the heel block • §

It should be about 270 - 280 mm long

If the remainder is long and closer to 305 - 315 mm, STOP! •

Remeasure and make sure the three measurements add up to

365 mm

§

If the measured heel block piece is greater than 250 mm, cut it off at the measured line • Mark the heel block piece for orientation L/R/Top so the grain matches when the heel is made • Smooth both faces of the cutoff by jointing or planing o One or two passes, only, just to make it smooth • Set this piece aside and skip to Peghead Veneers

§

If the measured heel block piece is less than 250 mm, cut it off at

250 mm, anyway • • •

Mark the heel block piece for orientation (L/R/Top) so the grain matches when the heel is made Smooth both faces of the cutoff by jointing or planing o One or two passes, only, just to make it smooth Set this piece aside

Neck Thicknessing Setup - For a Short Neck o

Before the peghead was thicknessed, the angles on the top and the back of the peghead were overlying each other At this point, they do not o This next set of steps will move the angles back together, if the neck has • become too short for the scale length, as determined in the last step

19


Chapter 1: Neck

o

This is done by thicknessing the neck, which will move the top angle towards the peghead

o

The finished neck thickness at the nut with the fretboard in place is about 21 mm

o

At the back peghead angle, measure the thickness perpendicular to the neck up to the surface of the peghead •

If the thickness is 20 mm or more, mark a line at 20 mm measured from the back of the neck

•

If the thickness is less than 20 mm, move up the neck until the thickness to the top of the peghead is 20 mm and mark this point

•

This will be the junction of the nut with the peghead used in the next step

Thickness the Neck •

Joint the Neck o This can also be done with a hand plane o While the neck at the nut needs to be 20 mm, it needs to be closer to

24 mm at the heel

§ This is accomplished by staggered jointing o Joint the neck by thirds § This is a dangerous maneuver on the jointer • Use a push block and do not hold the peghead while it is over the jointer blade § § §

§

Use thin cuts (0.5-1 mm)

Begin at the peghead end Be sure to press down on the peghead end of the neck with each jointer pass • Otherwise the neck will not taper and the heel end will be too thin Joint 1/3 the length of the neck • •

§ 20

Notice whether peghead angle line is square If not, adjust the pressure on the neck to try to get it square on the next passes

Second pass is of 2/3 the length of the neck


§

Chapter 1: Neck

• Push down on the peghead for the second and third passes Final pass is full length • Repeat until desired height is reached at the nut •

If after a full pass, the thickness at the nut is almost 20 mm, make only full passes until 20 mm is met

§ §

•

If it is still not square at the peghead, mark a square line and true it up with light block plane passes Check the flatness of the neck • Block sand if needed

Remark the scale length

o 0 mm = nut/peghead joint

o Add 5 mm = nut/fingerboard joint o Add 325 mm = 12th fret

o Add 35 mm = heel block •

If the neck is still too short o Thickness the neck further § §

Avoid getting thinner than 17 mm

Remeasure the scale length after each full pass

Peghead Veneers •

See “Online Classical Guitar Building Course”: Gluing Peghead Veneers

•

Make sure the veneers overhang the neck angle by 6-8 mm when this step is complete

•

Clamping o 6 - C-clamps o Spring clamps o Two peghead cauls o Wax paper 21


• • • • •

Put the neck on its side on a piece of wax paper Use thin applications of glue between veneers Glue up one veneer at a time and let it sit for a minute Bump veneers flush against the bench

Double check the overhang of the veneers past the angle of the neck 6-8 mm

•

Apply cauls and spring clamps o Check for skating of the veneers o Double check the overhang of the veneers at the neck angle Lightly apply two C-clamps and cauls to avoid skating o Again, check the overhang of the veneers o Flip the neck over and check that the veneers are flush on the one side o Lightly apply the other C-clamps Wait a few minutes for the glue to set up, which should prevent further skating, then tighten the clamps Add cam clamps or spring clamps where the veneer overhangs the nut

•

The heel block can be glued on now, if desired, see Attach the Heel Block

•

30-60 minute clamp time o This timing usually works for one or two veneers o If using multiple veneers, leave clamped for a few hours, preferably overnight

•

The heel block can be attached in the next step while these clamps are on

• •

When the peghead clamps are removed, scrape the glue Band saw the veneers almost flush on both sides, then take them flush with a hand plane

•

•

•

Attach the Heel Block

22

Chapter 1: Neck

•

See “Online Classical Guitar Building Course”:The Heel Block

•

Retrieve the heel stack cut off


Chapter 1: Neck

•

Be sure it is marked for orientation on the sides (L/R/Top) If not already done, joint/plane both faces of the cutoff Divide the heel block into three pieces and mark them in order on the side Cut and stack them in order o The piece originally closest to the neck is the top piece Stack and glue the heel pieces to the end of the neck on the correct side(!) o Do not let blocks slip towards the nut end of the neck § It’s OK if they slip a little past the end of the neck Use cauls and 4 C-clamps

•

30-45 minute clamp time

•

•

Block plane the sides of the heel so that they do not protrude beyond the side plane of the neck, i.e. so the neck will lie on its side square to the table o If there is no protrusion, no planing is needed o Do not plane the neck Remark the scale length on the top of the neck

•

Cut off or power sand the end of the heel block just enough to make it smooth

• • • • •

Cut the Veneer Overhang

o Table saw method o Square a line at the peghead angle (the nut) on the sides of the neck, perpendicular to the neck surface, not the peghead surface o Check that the miter gauge is square to the table saw blade, and that the blade is square to the table o Use a flat riser board to lift the neck and veneers off of the table saw surface o Set blade height § Place a second piece of flat wood on the riser board and extend it over the blade §

Set the blade height just below the riser board (1 mm )

Make a test pass over the blade with the saw running to make sure the board clears Set the test piece aside and place the neck top side down on the riser board §

23


Chapter 1: Neck

o Put the miter gauge past the blade o Put the neck and riser board against the miter gauge o Cut in multiple passes § Line up the veneer for a cut § Turn on the saw and make a pull pass § Turn off the blade § Line up, again, and cut § Repeat until the nut line is met • Do not go past the nut line o Finish trimming off the veneer with a chisel •

Hand saw method o Method #1 § Clamp a block of wood with a straight edge to the peghead § Line up the edge with the nut line § Hand saw against the block with the saw blade standing perfectly upright § Stop when through the outer layer of wood • As a clue, the sawdust may change to the color of the veneer § Finish trimming off the veneer with a chisel o Method #2 § Take a block with a squared end and cut out a rabbet on the lower corner just high enough to slide over the veneers and reach the nut line • Clamp the block to the neck, aligned with the nut § Hand saw against the block with the saw blade standing perfectly upright § Stop when through the outer layer of wood • As a clue, the sawdust may change to the color of the veneer § Finish trimming off the veneer with a chisel

24


Chapter 1: Neck

Cut the Heel Slots at the 12th Fret •

See “Online Classical Guitar Building Course”: Slotting the Heel See “Luthier Tips du Jour”: Spanish Heel

•

Cut or sand the end (not the bottom) of the heel block square

•

Square a line from the 12th fret line down and across the heel stack

•

•

Mark the centerline on the end of the heel

o Square lines 5.5 mm from each side of this centerline

•

Cut slots o Table saw § §

Use a thin kerf (2 mm) blade

Tilt the blade just enough to see that an angle is there

(2-4o)

§ §

Put the neck in a miter gauge, left side down Put the heel against the blade and set the height of the blade to the

5.5 mm line, being sure the neck is flat

§

Use a spacer block and adjust the fence to align the neck with the blade • Align the neck so the blade will split the line at the top of the blade •

If the heel block is small, move the cut out a few mm

§

Remove the block and make the cut

§ § § §

Place miter fence in the guide backwards Flip the neck right side down and position it against the miter gauge Push the neck against the spacer block Remove the block and make the cut

25


Chapter 1: Neck

Veneer the Back of the Peghead •

The seam between the back of the peghead and the neck can be hidden with a layer of veneer o This is an optional step

•

Use a template or measurements from the plans to be sure the veneer is long enough to cover the finished peghead length The profile of the back of the neck at the peghead junction needs to be determined now if veneer is going to be applied o The contour is often a smoothing of the joint into a gentle curve Shape the back of the neck at the junction with the peghead o A spindle sander works well o Do not cut into the back of the peghead

•

•

•

Glue up o Do a dry run o Test fit the veneer o Apply glue to the neck o Lay the veneer in place and tape the ends to prevent skating o Use a closed cell foam pad as a caul over the veneer o Cover with a thin layer of plywood (1/8”) o Clamp the caul with 6-8 C-clamps § The wood may start to crack, which is okay

•

26

Clamp time 2 hours


Chapter 1: Neck

Peghead Shaping and Tuner Holes Shape the Peghead • •

See “Online Classical Guitar Building Course”: Shaping the Peghead See “Luthier Tips du Jour”: Drill Press Router

•

Make a peghead template using the plans o Slot spacing is critical o Use the plans for the everything but the far end, which is designer’s choice o Mark a centerline on the template o Mark the location of the middle tuner holes § The middle tuner hole is exactly midway down the slot § Mark this point on the centerline o Mark the outer perimeter of the template o Cut out the template and fine tune to the lines by planing and sanding o After the template is completed, draw lines square to the outer edges of the template through the mark for the middle tuner that is on the centerline o Make a bevel at the near end of the template to accommodate the angle of the neck when the template is attached to the backside of the peghead for shaping

•

Attach the template o Find the centerline on the back of the neck, not the peghead, and transfer that line to the end of the peghead using a flexible ruler o Line up the centerline of the template with the peghead o The near end of the tuner slot is positioned 25-30 mm from the nut o Firmly attach the template to the back side of the peghead with double stick tape o Cut away all the exposed double stick tape outside the perimeter and inside the tuner slots

27

Construction Notes for a Classical Guitar •

Chapter 1: Neck

Cut Out the Peghead

o To cut the peghead shape, use a piece of 4 mm diameter drill bit stock ground to an 8 mm long bevel (home made)

o Mount the bit in the drill press

o Set drill speed over 2000 rpm o Position the peghead top face down on a sacrifice block o Run the bit around the perimeter of the peghead template flush with the template, cutting about 3 mm deep

§ Be sure the template doesn’t move for the first few passes § After that, the cut slot will serve as the guide o Clear chips after every cycle

o Advance depth slowly (3 mm) until all the way through the peghead plate o Go slowly on the last few passes to avoid tear out

Drill the Tuner Holes • •

See “Online Classical Guitar Building Course”: Drilling Tuner Holes See “Luthier Tips du Jour”: o Drilling Tuner Holes o LMI Peghead Slotter § This video shows an alternate jig

•

LMI Tuner Hole Jig o Double clamp the jig to the edge of the bench § Raise the jig on a shim so that the holes will be centered vertically on the peghead § Be sure the side of the peghead is flat o With the top side down, position the peghead flush behind and against the jig, lining up the lines for the middle tuner hole § Clamp the peghead down firmly with cam clamps § Using the tuner stem length plus the length of the jig hole, determine the depth to be drilled • §

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Use a 13/32” drill bit

• Mark the drill bit for the depth of cut Drill holding the peghead firmly with the other hand


§

Chapter 1: Neck

• A few passes will be needed to clear chips Check depth of holes with tuners • Turn the neck around, secure and repeat • Some of the holes will cross the midline, which is not a problem

Cut the Tuner Slots •

See “Online Classical Guitar Building Course”: Cutting Out Tuner Slots

•

Return to the drill press o Cut around the perimeter of the slots starting in the center of the tuner slot and moving out to use the slot template edge o Clear chips with each pass § An air compressor is helpful to avoid having to raise the bit to clear chips

o Advance 3 mm each pass o Make final passes slowly for a crisp cut o Insert the tuners to check for alignment o Remove the template carefully, using a spatula from the nut end, if needed

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Chapter 1: Neck

Cut the Top Relief •

See “Online Classical Guitar Building Course”: Top Relief on the Heel Block

•

2.5-2.7 mm needs to be removed from the top of the heel block to accommodate

•

•

the thickness of the top when gluing it down If using a double top, make the top before continuing, so a final thickness is known (Chapter 5.1: Double Top) o This can be done by hand, with a router or table saw o DO NOT go past the heel slots onto the neck o The cut can be fine tuned to the line with a chisel o Do a test cut when using power tools Router Method - ¼” bit

Use a sizing shim to set the desired depth Do a test cut and insert the shim into the cut to confirm depth Clamp the heel into a vise Make the cuts shy of the heel slots § Free hand the router or use a small fence on the neck o Finish with a chisel o Test the height with the shim o o o o

•

Table Saw Method o Use a miter gauge and a riser block o Make a test cut with a piece of wood overhanging the block and set the height of table saw blade to cut 2.5-2.7mm

o Put the neck on the riser block and gradually make cuts from the end of the block staying shy of the heel slots o Finish to the line with a chisel o Smooth out the cut lines with the chisel

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Chapter 1: Neck

Shape the Heel •

See “Online Classical Guitar Building Course”: Shaping the Heel and Tapering the Neck

Shape the Front of the Heel •

On one side of the heel at the base, make a mark 30-35mm forward of the heel slots o Draw free hand the front heel curve up to the neck, with a little posterior setback o Band saw and remove the wood in front of the line o Do not cut into the neck

Shape the Sides of the Heel •

•

• •

Draw out a heel cap on the bottom of the heel beginning at the slots

o Make it 25-30 mm wide at its base, coming to a point at the front of the neck base From the widest point of the heel cap on both ends, mark roughly square lines forward from the slots to the front of the heel o Carry the mark around the front of the heel just to be able to see the lines Clamp the heel into the bench with the peghead straight up, and the slots above the bench surface Hand saw at an angle the line from the just marked points on the front of the heel to the upper outer corner of the heel where it joins the neck o Do not cut past the slots into the heel block

Finish Shaping the Heel Block • •

Plane and/or disc sand the sides of the heel block so they are square Round the side vertical corners of the heel block by sanding or chamfer with a plane

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Chapter 1: Neck

Cut the Heel to Height • • • •

The target is 88-90mm from the base of the relief cut on top of the heel block Band saw off the excess Make another cut on the heel cap to angle it up a little

o This is to account for the 15’ radius of the back If the heel is not tall enough, make the bottom flat and add a piece of scrap neck wood or decorative wood

Taper the Neck • • •

Mark on the back (underside) of the neck

At the nut, mark 30 mm to each side of the centerline, a total width of 60mm

At the base of the heel, mark 35 mm to each side of the centerline, a total width

70mm

• •

Connect the marks lengthwise making tapered lines Band saw the excess off

Seal the Heel Block •

See “Online Classical Guitar Building Course”: Sealing the Heel Block

•

Sand the heel block to 180-220 grit o Mask the slots, top and bottom of the heel block o Seal the back and sides with shellac or other sealer o Make a satin finish with wax and steel wool o Remove the masking tape

Carve the Peghead Slots

32

•

See “Online Classical Guitar Building Course”: Carving the Peghead

•

This can be done after the guitar is fully assembled, but it is much easier now

•

Clamp the neck in the bench vise with the peghead overlying the bench

Construction Notes for a Classical Guitar • • • •

•

• • •

•

Chapter 1: Neck

Put tape on the peghead between the near end of the slots and the nut to use as a marking surface Protect any other areas desired with tape Extend the tuner slot outer margins onto the tape with light pencil Draw the shape for the near edge of the carving: straight, curved, builder’s choice o A sound hole cutout works well as a curve template Saw cuts o Saw on the lines from the tuner slots back to the near margin selected o Deepen the saw lines, but saw no more than 1/2 the thickness of the peghead within the slots o Make relief cuts in the rosewood to be removed Roughly chisel out to the line, then fine tune, making sharp edges o Japanese rapid cutting files also work well Watch symmetry Clean up o Remove tape o Fine tune with fine files o Use sand paper on a stick Check guitar string path for obstruction o Insert tuners o Use a scrap piece of string and simulate the string path to the tuners o Adjust the slots if the strings are scraping the peghead

Notes:

33


34

Chapter 1: Neck

Construction Notes for a Classical Guitar - sample

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