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Hello friends,
I lately bought this very beautiful masterpiece and i want to transform it into a flamenco guitar.
Except the strings I would like to lower its action . I mean sanding the wooden part too because the lower bridge is already low (the white part) and make the strings closer to the neck and the sound hole so the playing will be more comfortable and the sound gets more flamenco'ish.
What do you think and what do you suggest ?
Thank you.

Skan, very difficult to tell from your photos, but shaving the bridge and lowering the saddle is not a very good fix. From the first photo, looks like the action is very high (really hard to tell though), suggesting a rather distorted top around the bridge area or the neck is bowed. I will assume the neck was set correctly when built and that it is an integral neck ala classical guitar tradition.
If the bridge is tilted at an angle with the rear higher in the plane of the top than the front, you likely have a distorted top. Most all tops distort a bit, but excess distortion raises the action.
The neck may be bowed some, causing raising of the action, or it may be a combination of the two.
I am not familiar with the builder, but I am no classical guitar maker. It would be best if you could take the instrument to a reputable repairperson for evaluation. Your photos just don't tell us much...

Thank you for taking some time to answer . Here are more pictures :

Think about this...dropping the saddle 1mm will drop the action at the 12th fret 1/2mm. Normal action for a flamenco guitar is around 3mm at the 12th (6th string) meaning the saddle would have to be lowered 8 mm which is impossible. I would call this action very high even for a classic. It would require extensive and rather expensive work to make this into a quasi-flamenco guitar. Better to just buy a flamenco guitar if that's what you want.

OK, what we need is a photo taken from the bridge forward along the bass edge of the neck. We want to see if the neck is bowed. If you have a straightedge that will go the length of the fingerboard, you can determine the bow yourself. Set the straightedge on the first fret and let it run out to the last. Measure the string height off the 12th fret to the bottom of the straightedge.
The next thing we need is for you to take another side shot like the first with your hand out of the way and a square sitting on the top and showing that the rib (side) is square to the top.
A third shot could be taken from the rear of the bridge with a straightedge across the top. That would show us how much the top is bowed up. You can also measure that yourself. Prop up the straightedge at each edge of the guitar to make sure you get the same measurement on each side, bass and treble.
Looks to me like you have some "rotation" of the bridge, and I would suspect the neck is bowed up too.
One last thing is to make sure the rib is fully in contact with the neck at the joint and there is no gap. We really don't know if this is a "classical neck join".

Also assuming the bridge is glued down tight at the back end...

This guitar is not a candidate for Flamenco action. As others have mentioned unless you change the bridge and perhaps deal with the rotation that end of the "speaking length" of the strings is maxed out as low as it will go.

You likely can cut the nut slots though and gain a bit of lowering this way. I always set the nut slots low independently of anything else except the truss rod adjustment which is moot with this one. In my experience Classical builders and steel string builders leave nut slots way too high. No offense intended to anyone but I make my living cutting nut slots because my customers agree with me that their nut slots were too high.

Anyway take it to a Luthier who knows how to cut nut slots and you could gain some lowering this way.

Lastly lower tension strings may decrease bridge rotation and lower the entire top and bridge a small amount. This with properly cut nut slots may get you closer but it's highly likely that this guitar is again not capable of flamenco action. The lower tension stings will help the human, you feel like the action is lower.

Agree that this is probably not going to end as a flamenco without some major reconstruction. Just hard to say what the problem is from the photos provided, but doubt nut slot filing will do much. I'm guessing that there are a large number of problems with this instrument including top, neck and maybe even back flattening out lengthwise.
Repair may run quite a bit to renovate the problems with the guitar. I am sorry but we just can't tell enough to help you. As we have said, "in hand" visual analysis by a professional repairperson is the best way to proceed...

Looking at the side picture and using the string and body as a visual straight edge it looks to me that the nut end of the neck is tilted forward 6 mm or more instead of a normal 2 mm or even flat. That would also explain why the action is 2-2.5 mm higher than even a typical classical guitar even with saddle lowered. I can not tell if the neck is bowed or the guitar is folding up. It looks like it is folding up. If the guitar has a spanish heel I would remove the back and rig up the guitar so that I could glue the back back on with the neck angle set properly.

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http://www.Harvestmoonguitars.com

Cutting nut slots is not how to set action but if the thing already has nut slots that have not been cut properly it most certainly can be helpful to lowering action.

Often in setting up guitars our success depends on getting what we can where we can get it.... If the saddle can't go down any more perhaps the neck can be straightened with the truss rod. Or the nut slots need to be cut and in combination with a truss rod, moot on this one I know or lower tension strings you can easily gain 1/64th" of lowering with the help of cutting the nut slots.

For example as someone who sets up fleets of classical guitars for the local five universities these inexpensive guitars often have nut slots that are more than 1/64th" too high. Cut them properly and you gain 1/128th" of lowering of the action at the 12th. Add in something else that may lower action a tad and you can easily gain just enough to make it better and make someone happy.

I had an instrument with a seized truss rod last week and no budget for exploring at any length how to remedy the truss rod. The easy fixes didn't work, backing off the nut, lubbing it, washers, etc. It was seized in any direction and again with no budget.

For you guys who do not repair guitars professionally you may come up with ideas that could help but for anyone who's done professional repair work for any length of time you will know that if you break it you own it..... Or, in other words the best of intentions can put your arse right out of business and has in the past for Luthiers who could not help themselves.....

Anyway with no truss rod adjustment all I had were three things to gain any lowering of action. The nut slots, the saddle, and lower tension, lighter gauge strings. With all three of these things I was able to take the action from 8 and 10/64th" at the 12th to 4 and 6/64th" at the 12th or right in the Martin spec for a dr*ad.

This is not an uncommon thing either. No one brings us instruments to repair because everything is working fine.......

On a typical G*bson right from the f*ctory it's likely that some of the nut slots will be over 1/64th" too high......

Anyway it's an option and does not require attempting to rebuild the instrument either.

Regarding the California Neck reset, they call it a Michigan neck reset since no one wants to own the abortion of a procedure.... that's a huge and very invasive operation also requiring refinishing AND often can make things worse when it doesn't work. One of the top shops in the country was sued over a California neck reset that went bad and this shop lost $1,000 in compensation to the owner, $600 in having to rip up the repair bill and the player lost a coveted, rare guitar..... The shop also lost a customer for life.....

I would consider this a very last resort and usually not even an option at any cost..... There is a reason why no one wants to own the name(s) Michigan or California neck reset..... Bending an instrument into submission is just not a very good idea.

This is a relatively pricy and generally well regarded guitar. I understand the OP idea of making it a flamenco as the string height over the top can be 4-5 mm lower than a typical classical guitar. That would either require a new bridge or modifications to the existing bridge. Looking at the pictures this guitar needs a combination 5 - 6 mm of nut and saddle height adjustment to make it playable as a classical guitar 7 - 8 mm to get it to the range of a flamenco. So a lower bridge and saddle would make it more playable but still would have a pretty high action especially for a typical flamenco. There is is too much of a change for a lot of the simpler fixes for a classical guitar, like pulling the frets and planing the fretboard to the correct angle or pulling the fret board and installing a wedge.

I do not see a way to get there without a neck reset. If it is a spanish heel I imagine a California neck reset would be to lift the fret board extension and yank the neck angle in place and glue the fret board back down. The fret board becomes a strap to hold the neck set in place. I am not sure how well that would work or hold.

When I make a classical guitar with a spanish heel the neck is set after the neck, top and sides are assembled by having the neck clamped at the correct angle to the solera and using the back and the large foot on the heel to hold the neck angle. When making a guitar it is really the easiest type of joint to get a correct neck set as the heel block (thus the upper bout top) and the neck are always perfectly in plane, never a ski ramp or hump.

Repairing this guitar would be a major undertaking. There must be a reason it is folding up more than its age would warrant. If it was my guitar I would consider it a terminal case, that is little to no value unless repaired. If I otherwise liked the guitar I would risk pulling the back and properly reassembling the guitar. Having said that I turned down a friend who asked me to repair a classical guitar only a touch worse than this one.

The frets.com site has a tutorial http://www.frets.com/FretsPages/Luthier/Technique/Guitar/NeckReset/BCRIchReset/bcrichreset1.html to convert the neck to a bolt on and also suggests the possibility of pulling the fret board and installing a wedge.

_________________
http://www.Harvestmoonguitars.com

I don't know why everyone thinks this guitar is "folding up". I've seen many Spanish factory guitars with ridiculously high action. The OP wants a guitar with flamenco action, the only proper way to get flamenco action on this guitar is by removing the back and resetting the neck. I've done it many times, it's very time consuming and therefore very expensive but it has always worked for me although sometimes it's easier to put a new back on than to try to salvage the original one. If the action weren't so high one could back plane the fingerboard but that always entails the risk of the neck warping and it's cosmetically unattractive.

Probably all speculation at this point as the OP seems to have left the building...

Yeah, but speculation's fun!



Maybe. Maybe not. I see lots of interrelated questions that need to be answered before declaring the best "Fix"

How much of the high action is due to bridge height/ lifting, top distortion, excess neck relief, or some combination of all of them? would fixing any or all of these be enough to get the action at the desired height

How is the saddle position/intonation?

Do the distortions look as though they happened all at once, as in a "heat event" or as a result of under building? A single heat event means when things are put right, they will likely stay that way. Under built means adding strength somewhere somehow will be necessary.

Some builders taper the fingerboard to achieve a negative neck angle. Planing the fingerboard or "topping" it with another one often looks fine on these.
Is the neck 24mm thick under the first fret or <19mm? Is it already fat at the ninth? or is the neck shaft parallel?
If fingerboard thickness is reduced a lot at the nut end will it produce too much string contact on the way to the rollers?
Planing down below the fret slots and creating a angle correcting wedge with the old board can reduce the refinishing/binding required from loosening/removing the back.

As soon as possible I would ask Skan what the goal is and say this instrument is beyond any DIY sanding on something. Getting the action down to a comfortable height is almost certainly $800 or more. The quicker I get to this first fork in the road the better for both of us.

I would tell him I fix instruments for more than their value all the time for sentimental reasons but if you're just looking for a good deal on a flamenco, imagine you had the $800+ you would spend on this repair to go shopping with. would you still choose this one?




This phrase has me wondering, is 51 too old to get a first tattoo?
I'm think'n vertically, right along the back of my hand, up my right arm. That way, everytime I turn the key to unlock the shop or file a nut slot it's in view. Having to explain it 10 times a day to those who ask would serve me as well.

The answer to your questions is No. The action is too high to ever get this guitar to a "flamenco action" without removing the back. I've used all of the solutions you state on various guitars but none of them had actions as high as this one.

One needs to understand that this is not a flamenco guitar, it wasn't designed to be one and never will be one. There's more to a flamenco guitar than simply action. Why waste the money trying to convert this classic guitar with very high action to something it was never designed to be?

Hesh

You said that one of your tweaks for action is lighter strings - does this lower the action or make the existing action easier to handle?

Ed

The less the string tension the less the guitar is bending nut to saddle (if that is the guitars problem)

_________________
http://www.Harvestmoonguitars.com

Both. The action is effectively lowered because there is less relief in the neck. And since the strings are easier to play action settings matter less when a tad high.

Often when an instrument is compromised in some way, no truss rod, needs a neck reset it takes a combination of all things that you can get to make the difference and often that difference is enough.... for now.

Yep that too!