Making a solid body… body part one

Today we’ll go about how to make a solid body body, part one.

If you want to be boring and build a Strat or Tele, the easiest way is to buy parts from a number of suppliers. Just don’t let me hear you call yourself a luthier!  I can’t tell you how many times I’ve heard “I build guitars too” only to find that all they did was put together an instrument from parts.  Don’t get me wrong, I think it’s a great way for someone to learn the workings of a guitar including set ups etc.  I had one guy come to me with a guitar he “built”, complete with a laser engraved logo of his name on the peghead, wanting me to make him a nut and completely set the guitar up.  This was his 12th guitar.  Learn to walk before you run!

This brings me to another thing: CNC.  I have had a lot of people getting into building that immediately want to jump into the Computer Numeric Control world.  To this I ask how many guitars are you going to build?  If it’s in the hundreds, I say good idea (assuming you can sell that many) but most times it’s just a shortcut to learning your trade.  Kind of like the idea that some pedal or new gadget will make me a better player.  Since it’s a computer it is also prone to s#@t in s#@t out.  I had a friend come to me wanting to make a neck for an old Guild Starfire.  He’s a competent repairman but doesn’t get into building much.  He supplied me with a fret board he had CNC’d .  First off the scale was wrong. The fret slots too shallow and the position markers, while a perfect fit in the cavities, were off center.  Doing all this by hand, the builder would have never made those mistakes or if he had would have caught them right off.  Besides, who wants to listen to a router all day!  Enough rant, on with the build.

If the guitar you’re building is commonly available (Strat, Tele, Les Paul etc), you can find prints and even templates available from many suppliers.  If you’re only doing one and have access to the proper tools, templates are not really necessary.  If you don’t have the proper tools then I suggest taking a night course in woodworking at a local school or college.  I have done this when I didn’t have a shop and it works out great.  Plus you have the added benefit of doing a project most everyone will want to check out.  After all it’s a guitar not a cutting board. Of course you can be creative and do your own design.  Why do something that’s been done a million times.  This is your chance to be original.

First you have to pick the wood you’re using.  This depends on what type of instrument you’re building and what kind of sound you’re looking for.  Fender mainly uses swamp ash and alder but has also used poplar to good effect.  Gibson on the other hand usually uses maple and mahogany, either alone or in concert.  A lot of shredders like Jackson used bass wood and of course, a lot of the Asian guitars have what I can only attribute as mystery wood because of the diversity available.  You can go to a hardwood lumber yard to pick up what you need but beware, most of these places only sell entire boards and this can be very costly especially with the exotics.  These boards are usually rough and sold by the board foot.  This means 1 inch by 12 inches long and 12 inches wide.  In example if you’re buying a board that’s 48 inches long and 6 inches wide by 1 inch rough you will be buying 2 board feet.  There are two confusing things to consider when buying the lumber.  One is it is measured in 1/4 inch increments, so 1 inch boards would be considered 4/4 or four quarter.  Since this is the rough you will not be able to get more than 3/4 of an inch in usable thickness.  The other thing is that hardwood lumber is rarely dimensioned.  Boards vary in both length and width because each tree is cut to give the optimum yield.  Usually, the more exotic the wood the smaller the tree (and more expensive).  Some wood, such as ebony and Brazilian rosewood, are often sold by the pound.  Most guitars will use 8/4 lumber so that it can be surfaced to 1 3/4 inches.  Some yards have mills so you can have them plane it to the correct dimension for a fee.  If you can’t find a board wide enough you will have to joint the board and glue it together.  Most people think that solid body electrics are one piece but that’s not usually the case.  If you look carefully at most Fender’s you will often find two or three piece bodies.  Jointing can be a pretty daunting task if you haven’t done it before but if you take the shop class you can benefit from the instructors experience as well as the tools available.

If this sounds like a lot of work you can always buy the blank from a supplier.  These are already glued up and surfaced so you can start out right away.  While the prices may seem high I find that you end up only having to buy what you need and usually it’s top notch quality with no checks, cracks and knot holes.

Next week, we get into wood butchery or what was once called one of the “dirty trades”.


Repairing a broken peghead

It’s often said that guitar stands are a repair person’s dream. To that I would add airlines.  I often get two or more broken pegheads a month.  Dogs, kids, vacuum cleaners, luggage handlers, they’re all out to get your guitar.

Electric guitars, such as the Gibson Les Paul seem to be the most prone to breakage because of the peghead angle and the heavy weight.  Although I see it most often in electrics, acoustics are not immune from this ailment.  Most of the breaks on those seem to be due to airline damage.  I just repaired a Martin “Eric Clapton” signature 000-28 from airline abuse.

Before we get into how to fix them, let’s see how first to prevent it.  If you must display you guitar on a stand, make sure it’s out of reach from anything that could knock it over.  Wall hangers are getting more popular (although in earthquake country where I live that could be problematic as well).  Some people even have furniture cases for their prized possession.  This has the added benefit of keeping the guitar humidified.  The simplest way to protect your instrument is to keep it in the case!  If you do travel with your guitar and can’t afford to buy it a seat, then make sure it’s in a very good case.  Most hard shells are not up to the task.  A Calton or similar case is the best way to go.  Even then you must take precautions!  Always detune your instrument and make sure the head stock is supported with a towel.  This is especially true when your guitar has heavy sealed machines such as Schaller M6 or Grover Rotomatics.  A careless toss by a baggage handler and snap goes the peghead.

If the peghead is cracked but the crack is not opened up, do not delay in getting it fixed.  The longer you wait, the more grime and oil etc. can get into the crack and make it harder to glue.  Some of these are very easy to fix.  Gently pry the crack open enough to get aliphatic resin glue (Titebond, Elmer’s carpenter glue, etc.) in and clamp the break. Make sure the tuning machines are off and you use clamping cauls that will not damage the finish.  Any glue residue can be cleaned off with hot water after it’s dry.  If you’re not able to get glue in the crack you can use thin cyanoacrylate (super glue) as it will wick into the crack.  I prefer to use aliphatic glue if I can because I believe it will bond better and if the cyano gets on the finish you will have to fix that as well.  I don’t  use epoxy for this (or most repairs) because it’s almost impossible to get into the crack.  I also feel that it isn’t going to give you as good of a bond as aliphatic will.

I just repaired an  old mandolin that had been “repaired” using a wood screw!  The neck was originally two pieces with a short scarf joint joining the headstock to the neck shaft.  The hide glue had failed and the first fix was to use more hide glue and a wood screw.  Unless you’re installing a strap button at the heel or installing tuning machines, screws have no place in guitar repair.  I can’t tell you how many times I’ve seen this kind of “fix”  and they never work for long.  This goes for putting a wood screw in the heel of a neck to re-attach that.

These repairs can be problematic.  The short scarf joint is not sufficient in itself to hold the neck together so another method has to be used.  On the mandolin I cleaned up the glue joint so the new glue would stick to the wood and after aligning the two pieces, glued it up.  After waiting a day, I used a router to make a cut in the neck between the headstock and the shaft 3/8″ wide and about that deep.  I’ve tried elaborate jigs to accomplish this and have determined it’s easier just to clamp the neck in and freehand the router.  I then clean the channel with a sharp chisel and make a piece out of Eastern hard rock maple to tightly fit the channel.  After this is glued in and dry, the maple is shaped to the profile of the neck.  I’ve found this spline works very well.

The next problem is to fix any finish that was chipped or cracked during the break.  If it’s a transparent color such as a cherry red or amber this can take a while to get right and sometimes may never be invisible.  If it’s a sunburst finish you can simply take the darkest color and move it down a bit to cover the crack.

I recently repaired a Gibson ES-335 that required nothing more that gluing.  The crack was fresh and no finish work was needed to make the repair invisible.  Only experience will give you the tools to make an estimate of the cost.

Replacing a bridge

Unlike neck re-sets this is not a repair that every guitar will need.  Some can go their entire lives without needing a bridge replaced.  A bridge can need replacement for many reasons.  Left in a car the glue can soften and the tension of the strings can pull the bridge up. The piece of wood used for the bridge can have an undetected crack and split.  In the case of some Gibsons from the 60’s, the plastic (yes I said plastic) bridge is bolted to the top and usually warps over time.  I’ve never been shy about what I think of a high priced guitar with a dime store bridge.  This goes for bridges with adjustable saddles.  These have no place on any acoustic!  Older guitars using hide glue can pull off because of fatigue.  Hide glue, being organic, can deteriorate over the years.  The bacteria present can break down the glue.  Some repair people shave the bridge down instead of doing a neck reset and this can weaken the bridge as well.  This type of “repair” has fallen out of favor for obvious reasons.  I just worked on such a guitar.

Now first we must evaluate whether or not the bridge is salvageable.  If it’s not then we must find a suitable replacement.  If it’s a bridge that’s common, such as a Martin, I just use that but sometimes, in the case of the plastic Gibson, you will have to make another one out of rosewood or ebony.  Make sure that the pin holes are the same spacing and the saddle slot is in the same area.  Of course if the intonation was off on the original, now’s your chance to correct that.  If I’m making a new bridge, I will make it about a 1/16″ bigger all around to cover any damage that has occurred or can take place taking the old one off.  Martin even sells such bridges.  I start by planing or sanding a blank to about 3/8″, cutting to shape with a bandsaw, then drilling the holes for the pins and finally cutting the slot for the saddle.  This is accomplished using a simple jig with fence attached to the router.

If the top has a dome shape (my tops are a 25′ radius) I usually sand that in before I cut it to shape.  That allows me to get rid of any rolled over edges from the sanding.  I do this by making a positive radius sanding block from my bigger forms used to radius the braces.

Once the bridge is completed, I make a heavy cardboard template for the top of the guitar, so that only the bridge is showing.  This is covered in aluminum foil to shield the guitar from the heat source needed to soften the glue holding the bridge.  I then use a silicone heating blanket with a timer and temp controller to heat the top of the bridge.  You can also use a heat lamp for this but I find the blanket does a quicker job of heating just the bridge area.  The blankets can go to 500 degrees so set the heater at about 250 degrees.  I use a block of wood clamped to the bridge to ensure good contact and I usually let it sit for about 10 to 15 minutes.

Once the heat is on I use several palette knives and a thinned putty knife to get under the bridge.  If It’s not budging, I put it under heat again.  I’m cautious about too much heat because I don’t want to break the joint combining the two top plates.  I’m also very careful of how much pressure I use with the putty knife.  I don’t want to take the top with the bridge, so slowly is the rule.  The bridge usually has enough mass to keep the heat sufficient to separate the bridge from the top.

If you’re going to use the old bridge, make sure you clean up any residual glue and splinters from the top.  You must then do the same with the top under where the bridge was located.  I use a sharp chisel to scrape away the glue.  This is also a good time to check the bridge plate underneath the top for any repair there as well.  The ball ends of a steel string can be tough on wood.  If it’s a mess you can simply glue a small piece of rosewood or maple on the bridge plate or spend $150.00 on a bridge plate repair tool from Stew-Mac.  While expensive the repair is almost undetectable.

I like to get my clamps ready at this time.  Deep throat “C” clamps work well provided they have a block of wood attached to the stationary part of the clamp to clear the “X” brace.  You can also buy clamps specifically designed for the task.  I’ve made a clamp that is similar to one that Charles Fox designed that consists of an aluminum plate with two threaded rods that go through the outside bridge pin holes and mate with a top piece of aluminum.  Once bolted together, there is no clamp to get in the way for cleaning up the glue.

Make absolutely sure both the surface of the top and the bridge are completely free of glue.  Fresh glue will not stick to dried glue!  Put a generous amount of glue on the bridge and don’t worry about squeeze out at this point.  If you’re not using the Fox system you can use plastic bridge pins to locate the bridge and make sure it doesn’t move while you’re clamping.

Now, you can clean up the glue before it dries.  Don’t worry if you find that some glue has escaped your notice as it will come off a finished surface when dry by using a soft cloth dipped in hot water.

Two more things have to be done the next day after the glue is cured.  You have to ream the bridge pin holes to the correct taper of your pins (usually 3 or 5 degrees, depending on the pin).  This is accomplished with a pin reamer (yes, yet another specialized tool) but in a pinch I’ve used the tapered end of a file by sharpening the tang.  Lastly, the bridge pin holes have to have a slot in them to allow for the strings to seat.  Saws are available for this but I like to use a Dremel and three different sized cutters to make the slots.  The slot must be rounded over in the direction of the saddle so that the string does not break at a sharp angle.

Now you’re ready to string up and play.


Hype and the guitar

Today, I’d like to back track a bit and go into what makes a “good” guitar.  First, I’d like to say that there is no best.  People who like my instruments tend to like what I like.  Bluegrass players are not going to like my fingerstyle guitars and that’s okay.  Also people who like a particular brand are usually very loyal.  If someone thinks his Taylor is the best guitar made, then it is for him, even if I don’t drink his particular brand of Kool-Aid.

What does give me pause is the hype surrounding the marketing of high end instruments.  The list of “BS” is mind numbing.  One company has a patent pending “hundreds of hand-carved grooves on the top and back in carefully selected acoustic panels, creating a resonance never before heard or felt on an acoustic guitar.”  REALLY!  Is that off center sound hole going to revolutionize the guitar world?  I think not.  That is not to say that people like Michael Kasha haven’t pushed real boundaries.  Just play guitars by two of his most famous practitioners, the late Richard Schneider and Steve Klein, but are they better?

I believe that good guitars are based on two things: Quality of materials and quality of construction.  I’ve had the privilege of overseeing over 25 instruments completed by my students in my building classes and every one has sounded extremely good.  Now I will say that to make a great guitar is a matter of practice.  Once you’ve made several and have evaluated your best instruments you can try and duplicate that process. There is no secret formula, no holy grail.

There are also the details of construction.  Some builders swear by dovetail joint necks.  I’ve done about half dovetails and half bolt on (about 25 of each) and I cannot tell any difference in tone or weight.  More and more luthiers are using bolt on necks and with good reason.  As I mentioned before, an acoustic guitar will eventually need its neck angle re-set.  A guitar has over 200lbs of pressure trying to draw the neck into the body and over the course of time the strings will get higher and higher.  The neck has to come off in order to accomplish this and with a dovetail it is the most invasive thing you can do to a guitar.  Think of it as heart surgery.  In a bolt on neck that is a much simpler procedure.  In the case of Taylor it’s a job that can be accomplished in minutes.

All this hoey goes for electrics as well.  I once read a review in a respected guitar magazine that said poplar was the contributing factor in making this particular guitar heavy because it was more dense than maple!  In what universe, I don’t know, but on this world the opposite is true.  Again there are no secrets.  Good materials, good construction.

My point is that play as many guitars as you can.   Even with well respected brands you will find differences in the same model.  You can play 10 different Martin D-28’s and only find one that floats your boat.  If you’re going to buy a guitar from a single builder try and play as many of his instruments as possible to see how consistent he is.  Obviously a cocobolo guitar will sound different than a walnut one but can you tell if it has good string separation?  Do the treble strings have the same balance and power of the bass strings (it’s easier to get a good bass sound than a good treble response)?  Look on the inside.  Is the construction neat, no sloppy glue joints?  Are the bindings and purflings nicely mitered?

Things I don’t do:  Count the grain lines per inch in the top.  Adirondack spruce typically has less lines per inch than Sitka.  Is Sitka better?  Don’t say that to pre-war Martin fans.  I also don’t get the idea of buying a guitar… any guitar online.  If you can’t play it, how can you evaluate anything about it?  I also stay away from big box stores, such as Best Buy and Guitar Center.  The guitars go from the box to the hanger and don’t benefit from any set up, intonation, etc.  I also like the idea of going to the local shop, which in most cases will match prices too.

So much for my rant, hope this helps you find the right guitar for you.