Bespoke Guitar Part Three

Now that we’ve got the body done, it’s on to the neck.

I start with pattern grade quarter sawn genuine mahogany.  This is a very stable and relatively lightweight wood that has been used successfully in both instruments and furniture. The first thing I do is to square it off with a plane, then cut the truss rod channel and the two channels for the graphite reinforcement.  Once this is done I cut the profile for the neck and glue on the peghead overlay, in this case, book matched camatillo.  My client wanted a slotted peghead so I used a jig I made to cut the appropriate slots.  After the truss rod and the graphite bars are installed the head stock is inlayed with my logo and the fingerboard prepped. In this case the fretboard is bound in rosewood to match the binding on the body.

Now I glue the fingerboard on, being careful to keep it aligned with the neck.  After it’s dry I start to profile the neck.  As I have mentioned before, I find this easier to do by hand as I can finish the job in about the same time it would take me to set up a CNC.

The final post will be finishing and putting the whole thing together.

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Building a Bespoke Guitar Part Two

Now the side braces are fitted and installed.  This makes for a much stronger side brace than the traditional tape Martin uses today.

I then mark and cut out for the braces on the back to be inlet into the sides.  This makes for a rigid structure that locks the back to the sides.  I put the back into the vacuum so that when it’s glued to the sides it matches the 15 foot radius I was so careful to create.

I repeat the same thing with the top, making sure everything is aligned.

I then trim the top and back in preparation for the binding channels to be cut.  Before I do that I mix a little water with yellow glue and coat the areas of the top.  When this is dry, it acts as a sizing hardening the soft wood in the summer grain so it has less chance of tearing out

Unless a customer requests it (not happened yet) I do all my purflings and bindings in wood.

Now we have a completed body. 

Next time… the neck.

Building a Bespoke Guitar

This will be the first in a four part series on what goes into a custom made instrument.  In this case, it’s one of my Fingerstyle models with a slot head and cutaway.

Most of my clients have had (and do have) several other high end guitars, usually by boutique builders such as Santa Cruz, Goodall, etc.  They have usually played several of my instruments and have a good idea of what they want.  Even though this is the case, I still ask a lot of questions and make sure I have an understanding of what it is they hope to achieve with a bespoke instrument that they can’t get with what they have now.  Sometimes it’s that they like the sound of my guitars and have specific ideas about neck width, wood choice etc, and sometimes it’s about the aesthetics.  Another consideration in what they’re playing now is what woods they have.  If every guitar is rosewood I will try to steer them in that direction.  That doesn’t mean they are limited in choices as there are many rosewoods to pick from and most share similar sonic properties.  A few of them include:  Camatillo, cocobolo, African blackwood, Madagascar rosewood, Brazilian rosewood, Indian rosewood, Amazon rosewood… and the list goes on.

After the woods are selected, I fill out a form that puts everything in writing and let them know what I think the lead time is as well as the nuts and bolts of the nasty issue of money.  I ask for a nonrefundable deposit of 25% of the cost.  This allows me to cover the cost of materials and guarantees their place in the queue.  I also tell them about the return policy should it be needed (haven’t had that problem yet).  I give them 72 hours to return the guitar.  It must be in perfect cosmetic condition and I will give them a full refund when I sell the instrument.  This is a very important point.  This is not something that can simply be put back into stock as I am not a big box store and cannot absorb those kinds of costs.  I think it’s important to make sure they know exactly what to expect, as this, to some extent, is a big leap of faith on their part.  They are entrusting me to make their dream guitar, and I feel it’s an obligation for me to not let them down.  Finally, I have them sign a contract and away we go.

Enough hot air, on to the build.

I’ll be documenting a custom guitar for Tim Pacheco, a professional musician from the central coast of California. He chose camatillo (dalbergia congestiflora) for the back and sides and bear claw Sitka (Picea sitchensis) for the top with a matching rosette and slotted peghead overlay and a cutaway.  All of my guitars have wood binding and purflings, in this case, rosewood binding with a black/white/black/white purfling for the top and white/black for the back.

After they’re jointed, they’re both cut out and thicknessed, and the rosette cut into the top.

Now the top and back are braced.

I use a vacuum pump and rubber bladder to glue the braces.

The vacuum is an excellent clamping system, in my opinion, much better than clamps or a go bar deck.  It puts an even pressure of 21 hg (inches of mercury) or about 10 1/3 pounds per square inch on the surface.

The sides are bent next, using a silicone heating blanket and a form.  I still bend the cutaway by hand with a hot pipe and set it in the form.

Next week the body takes shape.

Re-fretting a Bozo

While I’ve done a post on re-fretting a guitar I thought it would be interesting to see some of the tools I use.  A small three corner file to bevel the edge of the fret slot so that the frets go in easier and when they have to be pulled less chipping.This is the tool I made for putting the 30 degree bevel on the fret edges.  It uses a mill smooth file with a high density, low friction plastic base.Flush ground end nippers for cutting frets close to the board.This tool cuts the tang off the fret ends to go over the binding.This is a small needle file with the edges ground and polished so I can remove the sharp edges from the fret end.This contraption I call Frankenfretter.  It’s a sliding base I bolt to the drill press to support the guitar while I compression fret it.  Notice the Taylor fret buck, a massive support for the guitar body while I fret.And finally, the finished job.

Basic Inlay Part Two

Now that we have the positive in mother of pearl, it’s time to cut the negative on the fret board.

While it can be done with hand tools, dental chisels, knives, etc., it’s much easier to do it with a Dremel or Foredom rotary tool equipped with the proper router style base.  Bases are available from several companies or you can make your own.  For much of my time inlaying I used a Dremel but have, in the last two years, switched to a Foredom.  While either will work the Foredom is much more powerful and most important to me the motor is well away from my ears.  I still wear hearing and eye protection but it’s much more quiet having the motor several feet away instead of having the Dremel right in your face.  The downside is that it is considerably more expensive.

I start by setting the inlay on the board and using a lead holderI can keep the lead much sharper than I can a standard pencil giving me better results.  Some people use a white tempera paint and a scribe and while this works fine with ebony, using open grain woods such as rosewood, the paint will be very hard to get out of the pores.

I use down cut spiral carbide bits to cut the channel for the MOP.  I have three sizes 1/8″, 1/16″ and 1/32″.  I use the biggest bit I can to get the job done, saving the 1/32″ for only the finest lines and details (they break if you look too hard).  I also use very good light so that the pencil line is clear.  I start at the center removing the bulk of the wood before I attempt the edges.  Of course, ebony is much more forgiving than lighter woods because the fill is easier to match.  One thing I’ve found comes in handy is a fish tank pump attached to the base so that it blows the dust away as you go.

I now carefully test fit the pieces.  It is very easy to break them at this point.  I often find the first time the piece will not always drop in.  I mark the spot that needs enlarging and route out again.

I use two methods of gluing.  On big pieces, I use epoxy and black coloring, fill the void and wait for the glue to cure, then sand back down.  In this case because of the fragility and the closeness to the fret slot, I place the inlay in position and lightly glue them in place with a small amount of cyanoacrylate.  Then once dry I can use colored epoxy to fill any gaps, making sure to avoid the fret slots.  The final thing is to now cut for the open “a” and “o”.  I do this with the Foredom with the 1/32″ bit.After cutting I simply fill the holes with black enamel and I’m done.

The trick to this is, of course, practice. Most of all have fun.

Basic Inlay Techniques

This will be the first installment of doing a retrofit inlay on a 40’s Martin D-28.  While we’ll be doing a signature, something that on the surface is simple, it is very demanding in technique and execution.

The great thing about doing inlay is that there is very little in the need of tools.  With the exception of big manufacturers’ use of CNC, very little has changed.  A jewelers saw, a rotary tool, such as a Dremel or Foredom and you’re in business. 

The piece of plywood you see in the picture is called a birds mouth and it’s used to support the substance to be cut, in this case mother of pearl.

The customer was having the neck reset and a refret and wanted his stage name inlaid in the fret board.  After we picked out the type style, I made copies for adhering to the MOP.  After gluing the type I start making cuts using the saw with a very fine blade that is .011″ thick.  When you’re starting out I would recommend a heavier blade of .021″.  You will break less of them but are limited in the fineness of the cut.  With practice, you can use finer and finer blades without breaking them.  I can usually do an entire signature without breaking a blade.  The actual “Country” measures about 1 1/4″ so you have to be very careful in placement on the birds mouth, making certain it’s supported on both sides of the cut.  Other important things to remember are to make sure the blade is perpendicular to the piece and to use the full length of the blade.  If the blade is not at a 90 degree angle to the piece you will put stress on the blade and produce a piece that is very hard to fit.  Make sure that you allow the blade to do the work and not to force it.  By using the entire blade you will cut faster and keep the blade from overheating.

You will notice from the picture that I am using my two fingers on top and thumb on the bottom as a temporary clamp.  You might also find a magnifying head band works to keep eye fatigue to a minimum.

Another thing to take into consideration is keeping the dust to a minimum by using a shop vac.  The dust is calcium based and something you don’t want to breathe in.

The thick and thin letters in this can be tricky so I always look to the hardest part first.  In this case I did the bottom of the letters first because they had the most turns and would be the most likely to break.  I don’t stop the blade when I come to a 90 degree turn but keep the blade moving rotating it until I get to the position I want, then continue.  If you’re careful you can cut the entire piece without breaks but if you do simply super glue the pieces together when you’re done.  Small needle files can be used to clean up and rough edges and as you can see, in this case I left the “O’s” and “A’s” closed.  They will be engraved when they are installed into the fret board.

Next week:  Inlaying the letters into the fret board.

Color Match Finish Coats

Now that we’ve got the color match we can complete the finish.

I then spray the top coats.  I start by lightly spraying in alternate patterns.  Horizontal then vertical, and then switching to diagonals to get the most even coverage.  I shoot 2 to 3 coats a day then sand with 320 grit wet or dry, being careful not to sand through the color coat.

Lacquer and other top coats follow, they don’t fill.  That means that the lacquer will flow into the depression not fill it up.  By sanding in between coats you are taking off lacquer on the surface while not touching the depression.  The next time you spray, the depression will be that much smaller.

I usually spray between 6 and 9 coats to get the desired result.  Prep work is critical because the less depressions and holes you have the less you have to finish.

When I’m satisfied with the raw finish I let it dry for a minimum of 2 weeks to allow the finish to cure and shrink.

When the finish is dry, it’s not a simple mater of putting the guitar together. The finish has to be compounded to smooth out the ripples.  Compounding is going through a series of abrasives until the surface is smooth and mirror like.

I start with no lower grit than 600 wet or dry and usually 800 grit.  I use the best quality paper. 3M Imperial wet or dry seems to work well.  The cheaper papers have larger stray grit in them and can cause scratches that are almost impossible to remove.  This is also the case if you start with anything coarser than 600 grit.

The first sanding is the most important. I lubricate with water to float the particles off and for less loading of the paper. It’s very important that you use a hard rubber, cork or felt pad to be sure of a flat surface.  Never sand with you fingers.   I make sure all the gloss is taken off so that the surface is dull but smooth and uniform.  Now I switch to Micro Mesh.  This is an abrasive in cushioned latex that doesn’t build up as easily and is very high quality.  The 1500 grit is equal to 600 grit sandpaper so I start with the next one up, 1800.  I continue with this to 4000 grit also using water as a lubricant.  Then I switch to another abrasive, Abralon.  This is a 6″ pad I use with a 5″ random orbital sander.  Using 2000 and proceeding to 4000, I use these pads dry.  I leave the 6″ pad full size to protect the guitar from the rubber pad on the sander.  In tight corners, I use the pad by hand. One thing to remember is to clean off all the previous slush so that the next grit starts fresh.

Now the fun part, using a buffer to bring the gloss up!  In reality all you are doing in each step is to make the scratches finer and finer until they appear to go away.  I use a Shop Fox buffer and 12″ domet wheels.  I make sure not to contaminate the compounds with the wrong wheel.  While they make several grades, I stick with the fine and extra fine.

Buffing wheels can be very dangerous if you’re not careful with the way they are used.  Remember when you’re buffing to only buff the bottom half of your piece.  Right

Wrong.

If you use the buffer like this you will run the risk of catching the upper surface and having your piece thrown to the ground.  I believe you will not like the result much so be aware of your orientation.

I do the same thing with buffing that I do with sanding, changing direction of the piece’s orientation with the wheel: horizontally, vertically, and diagonally. When finished with the fine wheel, clean the surface of the piece to clean the previous compound then proceed to the extra fine.  Wax is not recommended and will in fact make the piece duller.

When you’re done you should have a mirror finish to be proud of.