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I have extensively repaired instruments in the past but I am an amateur. I was hoping for guidance on a project I just acquired. After years in the workforce, I have returned to higher learning and I am in a dorm room at University. With Covid, things are very restrictive and I needed a hobby to keep me occupied.

I acquired this guitar because the price was cheaper than it would have cost for me to buy all the solid woods and build it from scratch. I don't have much money and in no way can afford to pay someone to repair this guitar.

Back and Sides: AAA grade solid East Indian Rosewood or Pau Ferro
Soundboard: Master (AAAA) grade Western Red Cedar
Headplate: East Indian Rosewood
Bridge: East Indian Rosewood
Neck and headpiece: Paraguayan Red Cedar
Neck reinforcement: Ebony
Fingerboard: Master (AAAA) grade Ebony
Binding: Algarrobo
Rosette: Hand made in Russia
Tuners: Schaller Hauser Luxury Gold Tuners with White buttons
Finish: Nitrocellulose lacquer, and French polished top

https://www.classicalguitarra.com/

The ES in the model number represents its luthier Emiliano Sanabria.

Upon initial inspection, I have identified a number of issues and would like advice as to the best course of action and perhaps some instruction is necessary.

Top is appearing corduroy. There are 4 cracks. Three on the back and one on the top.

The bridge appears to be lifting along the edges.

Internal bracing appears to be in an odd configuration that I have not encountered before. It seems to be a variation on fan bracing. The bracing appears to be sound at this point but odd. Along the top crack, it runs along the grain under the bracing. When I say under it is because that part of the bracing does not touch the top, it has humps built into the design. I obviously have to check all the bracing with feeler gauges.

The neck does not have a truss rod and has a bit of an arch which is more drastic on the bass side. The tension seems to have not only permanently cause the bow but the twist.

When the guitar arrived it was strung so, of course, I strummed and plucked it for a few minutes and the tone of the guitar is wonderful and responsive. I appreciate any help that can be provided!

I have polished the frets with 0000 steel wool. I then cleaned the entire guitar with lighter fluid. I then applied music nomad polish to the guitar and oiled the fretboard.

Currently, I have put a dish sponge soaked with water in an open ziplock bag and dropped it into the guitar with a t-shirt stuffed into the soundhole. In less than 24 hours the top crack has swelled and when I put a flashlight inside of the guitar, with a little manipulation of pressure on the top the crack is closed.

Depends on how much work you want to put into this guitar but at minimum I'd suggest leveling the fingerboard to make it playable. I haven't seen top bracing done like that and am puzzled by the circular marks. It looks like the top is staged (thick in center thin on edges).

The action surprisingly isn't that terrible but will need to be addressed at some point for sure! When I do plane to correct the issue.... you suggest that I plane the fingerboard? or remove the fret board and plane the neck?

I'd almost rather just plane the bridge down. Does anyone advise against this for any reason? The bridge appears to have to come up and need to be reseated anyway

UCSC, I worked my way thru your pictures and here are a couple of observations.

Finish hydrating the guitar, glue the cracks and add some cleats to the inside. I see a package of hide glue - if you are comfortable using it that would be the best choice. The glue drips on the inside look like hide.

I wouldn't worry too much about the odd bracing scheme. I have given up on trying to keep track of all the different ways classical guitars get braced. Make sure the braces are tight, fix any that aren't

Classical guitars frequently have different fretboard relief than you see on steel strings. They often have very little relief on the treble side and a bit more on the bass side but it is more up the neck and rolls off towards the end of the neck. Relief tends to be planed into the neck and fretboard rather than allowing the string tension to pull it in. Before doing anything with the neck I would suggest putting a straightedge on the fretboard and seeing where the end is relative to the bridge and top. You want it slightly lower than the top of the bridge (unlike a steel string where it sits on the top). This will be slightly complicated by the neck joint - you don't have the option of taking the neck of and resetting it.

I don't understand why you would want to plane the bridge - just take it off, clean up the old glue and the top and reglue it. Make some good cauls, get a couple of deep clamps and it is a pretty straightforward repair.

Remember too that the action on a classical is typically much different than steel strings. It would have been nice to actually measure it back when it had strings to see how close you were.

What I see is a reasonable project that should give you a nice little nylon string guitar when you are all done.

Thank you, Freeman! Yes, I agree, after hydrating and after structural issues are addressed like potential loose bracing and cracks.... glue down the bridge and re-examine. I am excited. When it's complete maybe I can get into one of the music courses and up my classical guitar playing game! In the meantime, I will post progress and photos. It is going to take some time as classes are in session and I have quite a mountain of work. It's really helpful to talk with folks who know what we are all talking about. Thanks for talking this out with me! It is very helpful and appreciated folks!

If a photo clearly shows the twist in your neck and warp in the fingerboard it must be pretty severe. The guitar needs neck work. It's impossible to say how to proceed without examining the guitar. If the neck weren't twisted you might be able to correct it by installing frets with larger tangs.

If possible post your photos directly into the body of your text. You can do that by going to the advanced editor, choosing a file from your computer, adding the file (your photo). You may have to resize large photos. I found going thru your photobucket pictures a bit tedious.



I am far from being an expert on classicals but they frequently have the fretboard planed thinner on the bass side as it approaches the sound hole. That allows the saddle to be a bit lower on the bass side and still have the necessary action. I just completed a classical based on the 37 Hauser plans and it has a definite twist to the neck

Turns out the neck is an arrow! The relief is baked into the fretboard. Thicker by the nut.

Need to resize your photos to something like 675 by 900 pixels.

hopefully, this works better? The sag you see on the ruler closer to the nut is gravity. the neck is an arrow

What are you doing there? That is not a useful measurement.

My 37 Hauser plans (Brune) show 6mm thick on both sides of the nut end, 5mm thick on the treble and 4 mm thick on the bass sides of the fretboard at the sound hole. I built that into the classical that I just finished and the action is a hair over 3mm on the high E and about 3.5mm on the low E

That's super fascinating!

I've played nylon string guitars over the years. I've had a few of the old Hernadis and Garcia's and I also owned a Carl Barnie out of Connecticut. They all had flat boards. I normally play steel strings and electrics with radiused boards and truss rods. I didn't realize that this is common practice. I take back my comment about wanting to shave the bridge. Foolish Thought. Thanks for educating me! I have nice planes and hand wood tools but they are in storage far away. I have ordered the clamps and caul that I needed for the bridge. Clamps on Ebay were $12! But I couldn't find a caul domestically at a good price, so I had to pony up the $25 plus shipping from LMI for the caul. I'll have to deal with the higher action until I can get to my tools. Maybe the higher action will make me a better player in the meantime.

Currently, this board measures:
bass nut 8mm, bass body 5.5mm, treble nut 7mm, treble body 5.5mm

UCSC, just to clarify. True classical guitars almost always have wide flat fretboards with no radius. Nuts are frequently around 50mm. There is a whole generation of new nylon string guitars with slightly narrower nuts and slight curvature to the fretboards - the Taylor nylon is an example as well as many from Yamaha, Cordoba and others. These are aimed at steel string players who want to add a different voice to their playing.

The slight twist in the fretboard is one way to deal with action and relief on a nylon string guitar. Many of the hybrid guitars have adjustable truss rods and some have removable neck joints.

It sounds like yours is built on the traditional model. It would be worth your while studying up on the differences (Cumpiano and Natelson discuss it)

Yes the nut on this guitar is 50 mm

Removed the bridge. Like I said I don't have any of my tools so I'll clean this up with a razor blade.

It smells like hide glue in my room!!!! Vintage 2004 lol

https://ibb.co/ykc97nd
https://ibb.co/zX3xbQ9

If it is hide glue you can mix new with the old but I prefer to get every bit of the old off and have strictly clean wood to wood. Remember that you don't have much open time with hide so practice several times until you have the steps nailed. It is helpful to have your inside caul held in place with masking tape or something so you don't have to fiddle getting it in place. Warm both glue surfaces.

I almost always use AR on bridge repairs to get more working time unless it is a vintage instrument where hide would have been used originally and any one working on it in the future would expect to find hide.

So this just happened as I was tightening the lmi clamping caul down! Ordered a new slightly oversized one. https://www.allparts.com/products/gb-08 ... tar-bridge

I used an antique Stanley 103 plane to clean the slot in order to have good wood to wood contact paying attention and cautious of removing actual wood. I made fresh hide glue and used a simmering pot of water to get it to a good temp. It was rather thin, but that is how I like my hide glue. I used a 1 water/ .75 hide crystals ratio and used the old bridge for cauls on the wings of the bridge. I'll let that sit overnight minimum.

The total cost of bridge repair materials was $50 usd est. The most expensive item was the replacement bridge.... $20 with shipping for a 1mm oversized Indian rosewood bridge!

After restringing the guitar for a few days the bridge is solid. I have started to strip all of the finish and level the body using 39 grit sandpaper. I think the 39 has done its job and I am going to move on to 60 then 100 then 150 and 220.

I have started my polish. Evidently, California has outlawed Denatured alcohol! Seriously! I was able to use 80% hand sanitizer on a test batch and it worked fine. That was really expensive so I found some 91% isopropyl alcohol which I read would work fine.

Progress is good!

Sanding is hard work! Nitrocellulose on the neck back and sides. Shellac on top. Once the wood came out from under that nitro it really looks great. Got the whole thing to 220 grit. Arms are like rubber right now! I have some spots and scratches especially in the back to touch up but I should start the french polish tomorrow. I am really impressed with how beautiful the rosette is and cant wait to see it under the finish.

Photos of the back and Scratches

Building a finish.

Good base built up.