My First Classical Guitar

Photo of My First Classical Guitar

by Matt Jacobs

My guitar building resume has several different steel strings and an arched top in the finishing stage. Until now I had not had the confidence to tackle a classical guitar simply because I don’t really play classical guitar music. It became a project I was motivated to do and I wanted to do a respectable job even if it was my first classical guitar.

After consulting with several of my LINT amigos, I decided to use the Jose Romanillos pattern and thought I would write up the experience for others in LINT. The plans are available from Guild of American Luthiers - Guitar Plans.

It must be said that in preparation to build a fine guitar, accurate molds and templates must be made to assure a good fit and finish. Take your time during this phase and you should be pleased with your results.

Materials:
  • Back and sides- Goncalo Alves (medium curly figure)
  • Top- Western red cedar
  • Neck- Spanish cedar
  • Fretboard- Indian rosewood
  • Bridge- Honduran rosewood
  • Peghead veneer- Indian rosewood
  • Binding, rosette, and end graft- Snakewood
Joined back. BACK


Joined back- I jointed this using a power jointer to get it close, then switched to a shooting board and plane for the final touchups. I used titebond II and to join the halves

I joined the top in a similar fashion.



Gluing the two piecies of the neck. NECK

I cut the scarf joint at 15 deg angle using my band saw. 15 deg is a little steep for a classical but I figured it wouldn’t hurt.

I jointed the surface of the two pieces a la Cumpiano’s book. I then clamped them in the same manner except I drilled two small holes and inserted locating pins to keep the whole thing from shifting while gluing it up. The pins are located where the peghead slots eventually go.



Shaping the heel block. Scraping the heel block.

Above left- I draw the shape of the heel on the heel block then start shaping. First I start with chisels, gouges, rasps, explosives (just kidding) to rough out the profile.

Above right - I’m using a scraper when I’m “getting close”. Note the tape to help protect the neck block. Work carefully so as not to cause any damage to this area because it must make a good surface contact with the sides later. Also note I only carve out the heel and leave the rest of the neck uncarved. This way I have nice square and parallel edges to work with while shaping the peghead.

Routing template for the peghead.
Above - Here is a routing template I made using plywood and a CAD drawing of my peghead. I use 2 screws to hold the template on then I route out the pattern using a laminate trimmer. Make sure to use a sharp spiral cutter and be careful not to tear out the wood as you go slowly around the tight curves.
Carbon rod bonded into the Spanish cedar neck.
Above – Carbon rod bonded into the Spanish cedar neck.

During assembly, I use 2 ea. 1/8” dowels on my work board which will hold the neck in alignment with the center line of the body. Rather than drill corresponding holes in the neck, I routed a 1/8” slot along the length. Epoxy was used to bond the rod into place. The carbon rod adds stiffness to the cedar and in this combination produces a neck which is much lighter than a counterpart made from mahogany.
Sanding the ramps on the slots.
Above - Here I am using a dowel with sandpaper to cleanup the ramps on the slots. I cut the slots by drilling holes in the ends of the slots and cutting out the rest with a coping saw. I then cleaned up the slots using files and sandpaper. You can see remnants of the CAD drawing I glued to the peghead to help with the cutting.
I pre-drilled the holes for the tuner rollers prior to cutting the slots to have a clean bore with no “tear out” visible in the slots.
Right - I joined the top and thicknessed it using a drum sander. Here it is rough cut to size. I routed the rosette channel using a Dremmel with a trammel base attachment. The discoloration around the channel is shellac; it helps minimize tear out and will be sanded off eventually. Joined and thicknessed top.
Snakewood rosette.
Above - this is a snakewood rosette. I cut the pieces individually then glued them together using superglue. Next I glued the pieces to a piece of particle board and cut the whole thing using the Dremmel. Later I removed the piece and inlaid it into the rosette channel.
Gluing the bracing using a go-bar deck. Left - Gluing the bracing on using a go-bar deck. This is the first time I have done this using a deck; it is a tremendous time saver. Doing all of the braces individually would have taken 4 times longer. The trick with the deck is to use very little glue and hold the brace in place for a few seconds to “tack” before you apply the rod. This prevents the braces from sliding out of position during clamping. In this view, note that the flat side of my radius dish is actually being used because I wanted the top to be completely flat. So flip your radius dish over!
Right - Here is the completed top with the braces carved to their final dimensions. Notice there is no bridge plate. Romanillos didn’t add bridge plates until 1981, and Bo Walker (of LINT) recommended that I didn’t use one on my first classical guitar. I will use one in the future if I observe any out of control bass or lack of tonal balance between the strings. Completed top with shaped braces.
Two pieces of spruce form the back graft. Left – For the back graft, I used two pieces of spruce cut from the ends of tops. I put tape on either side to protect the back and started carving until I got the desired shape, which in this case is pyramidal
Right - I cut the cross-wise slots for the braces using a chisel and carefully fit them into the back graft. The go-bar deck is again used to glue them in place. The plan calls for 3 braces, but I thinned the back a little more than I wanted, so I added another brace to stiffen it up. Gluing the braces on the back using a go-bar deck.
Shaped braces glued on the back. Here are the final shaped braces glued in place.
Bending the sides. SIDES
Above - Here is my version of the cheapo bender. While the bender is cheap the two silicone blankets aren’t. I thin the sides to .080” and start bending. I start at 220-240deg and bend everything to shape then I heat the whole thing to 300 for 5 minutes. I let it cool down then heat it at 220 for 20 minutes to hold the shape.
Result after bending the sides.
Here is the result of the bend, not too shabby
ASSEMBLY Gluing the tail block to the sides.
The shaped tail block.
Above - Here is the shaped tail block, and it to the sides. Note- you can never have too many clamps!
Gluing the kerfed lining.
Above - I glue kerfed lining in place using binding clamps. I find they are a perfect fit for most kerfed linings, they are strong and cheap!
Gluing the top to the neck.
Above - I cut the top to shape so it would fit inside the mold. Then I glued the top to the neck, making sure the neck was aligned with the center line of the top.
Top, sides, and neck.
Top sides and neck- Sorry I didn’t take picture of this process (and this one is pretty blurry) but I’ll try to explain what I did.

I put the neck and top in the mold. I then fit the kerfed lining to accept the braces. When I had a good fit I put a thin layer of glue on the lining and clamped it onto the top. Shortly after I did that I glued wedges in place to clamp the sides in the neck joint slot at the heel.
Trimming the wedges down. Here is a picture of the wedges, and me trimming them down.
Carving the sides to get a rough match of the profile. Using the dish to profile the back of the sides.
Profiling the sides- I rough carve the sides using chisels and small planes. I get it as close to the final profile as possible I put the sanding dish on it and turn it back and forth until the back is shaped.
Next I glue the back half of the kerfed lining to the sides, and shape them using the dish.
Routed channels for the back braces. Channels for back braces - end result.
End result.
Fit the back. I put the back on top of the ribs and mark where the braces intersect the body, and route channels for the braces. I go through the sides; they will be covered up by the binding.
Block with alignment pin glued to tail block.
Here is trick I got from John Calkin. Superglue a block to the tail block and put an alignment pin through a corresponding hole on the back (outside of the outline). When you glue everything up you don’t have to worry about it moving out of alignment. When dry it is carved and sanded away.

Attaching the Back- I put the back in the radius dish, applied glue to the kerfed lining and flipped the rim so the top is facing up. I made sure everything was lined up and I applied as many clamps as possible.
BINDING
Routing the back before installing the binding.
I ran a thin layer of epoxy around the edge of the body to reduce tear out during the routing operation. You could also do the same thing with shellac. This makes for a very clean routed channel and the epoxy or shellac can be easily removed prior to finishing.
Gluing the binding in place.
Above- I bent the binding and purfling on the bender, and glued everything up using a small brush and titebond. I then used a bunch of tape to secure everything
Scraping the binding flush.
Scraping the binding flush
Fretboard/Neck
Fret press.
Above - I purchased the fretboard pre-slotted from LMI and I used a block plane to trim the edges to the final width. I also sanded a slight taper going from the 1st fret to the end of the board mostly on the bass side. Here is my fret press and a flat caul I made using friendly plastic (the white stuff). It worked surprisingly well! I ran a thin bead of titebond on the fret tang and pressed them in.
Installed fretboard Left - I glued the fretboard to the neck using alignment pins inserted in the 1 and 9th fret slot, I later hammered those in with a brass hammer. I also filed and sanded the curvature of the fret board to match the sound hole.
SHAPING THE NECK
Shaping the neck.
I used everything I had to shape the profile of the neck to the final shape.

Filling the ends of the fret slots with rosewood dust.
Here I filled the end of the fret slots with rosewood dust and flooded the dust with super glue. Later I sanded everything flush.
FINISHING
Fretboard taped and guitar body sanded before applying finish. Left - I taped off the fretboard and I then sanded everything level to 220.
Guitar body with pores filled.
Above - I filled the pores with epoxy and let it harden over night. I then sanded it back as flat as possible and applied another coat of epoxy using a cloth (rubber/muneca) and let that harden. I gave that coat a cursory sanding once it hardened. NOTE- make sure you don’t sand through otherwise you’ll have discolored areas under the finish.


Spray Nitro Lacquer Coats
  1. I spray 4 coats of sanding sealer, 1 hr between coats, then let dry overnight.
  2. I block sand until I have a perfectly flat surface.
  3. Spray 4 coats of gloss lacquer 1 hr between coats (last coat is thinned 50/50, lacquer/ lacquer thinner)
  4. Let the finish cure for 2 weeks prior to final rub out with micro-mesh and buff.

 

Finished Guitar.

Back of finished classical guitar. Front of finished guitar.

The resulting guitar was played by Andy Avera at the October 2006 LINT meeting and was well received by those in attendance. It was described as clear and well balanced. I expect that it will mature and improve with more playing time.

It was pleasing to see the positive response from so many experienced builders. I am probably going to have to build another with rosewood now so that I can evaluate this design further.