Fixing a warped guitar top with the Bridge Doctor

Someone made a really odd attempt at repairing braces inside this Gibson 12-string. That didn't keep the top from twisting into a wave shape. Dan Erlewine shows a simple fix.
JLD Bridge Doctor
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[@StevePietras]

Dan is THE MAN. I don't play guitar, I don't repair guitars but I know master craftsmanship when I see it. God bless him, love his videos.

[@DrCrazeKill]

Dan you are my hero and you make me want to become a luthier

[@banzospod]

I fitted a bridge doctor to an old beaten up fender F65( 1978 model) and not only did it cure the slightly bellying top but it gave the guitar a pretty mellow tone as well( it was a bit brash before.)

[@HeliBenj]

A video with Dan = instant thumbs up

[@curtishutchins1224]

Works on a classical guitar too! with a lot of modifications. I thought I would post here for the classical guitar peeps since none could be found anywhere on the internet... I have a late 70s Horner Contessa with a "belly", the guitar has a 1/4 in high X 3/8 in wide brace that ran right down the center of the guitar. This prevented the block from making solid, stable contact with the top. My solution was to cut a channel in the block 1/4 deep and 3/8 wide. The nylon post also needed to be shortened by 1/4 in. It took a bit of trial and error but I got both the post and block to have good contact with the top of the guitar. Also, the bridge on a classical guitar is shorter since there are no pins, I was concerned about the drill hole but in the end it worked out fine. As part of my Hack, I relocated the nylon post to accommode the narrower bridge, to keep the nylon post on the brace, I also moved it off center slightly. At first I wasn't sure if it was working but sure enough, the belly appears to be improving as the top relaxes... overall/ the action of the guitar came down about an 1/8 which is just what it needed and also the intonation at the 12th fret appears to be better. This is totally awesome. My only regret was the necessary drill hole. I managed to cover the hole with the supplied pearl dot. I glued in with clear nail polish which also helped to hide my drilling. For me, this was totally worth the price since luthier told me he want upwards of $500 to fix the belly. This guitar is a gem, but not worth $500. I'll live with the pearl dot on the bridge plate.

[@stevecusimano2116]

I don’t even play guitar but I find this so interesting to watch you do repairs.

[@Tom.Klingl]

My luthier did that with my 12-string which had the same problem - bridge belly, because braces were scallopped too much. It was built in 1981 and the problem evolved over time. It was really hard to play in the upper registers and string height at the 12th fret was way to high. The Bridge Doctor fixed all of that at the expense that there is a slight cut in the bass response of that guitar. But it still has plenty and now the top almost flat again and the playability is a dream.

[@izzynutz2000]

This is exactly what I have to do to a little Japanese Greco 12 string that I picked up in a pawn shop but it has pulled it down so bad it has to be re braced and reglued thanks for the insight you guys are the greatest

[@mellotronanism2097]

Brilliant device. Thanks for the great video, which gave me the confidence to do it. I’ve fixed a 12 string which had bad bowing and a detaching bridge. It now plays pretty well.

[@VadimLyutiy]

and this device will keep in guitar? how does it affect the sound?

[@PK-pi9uf]

My Breedlove acoustic guitar has something just like that bridge doctor in it. I enjoyed your video!

[@mattrogers1946]

Great video Dan. Thanks!

[@andrewdeck7945]

WOW what a great way to fix the issue!!!!

[@jerbear1601]

I did this bridge doctor fix to an old 12 string years ago my wife picked up cheap that was left in less than ideal conditions for a while and it did it's job really well. It didn't make it good enough for me but I could at least sell the guitar.

[@hgg6448]

I'm exactly in the same situation, with an old, battered and warped 12-string. On a scale of 1 to 10, how likely you'd recommend me to try it? I'm semi-skilled with woodwork, 0 experience with luthiery.

[@dadlaponizil3687]

Beautiful Dan. Thank you.

[@AgimLubonja]

Simply rocket science from the best!

[@Sungodv]

Dan Erlewine, a true American treasure.

[@tommyvega7948]

Make it an international treasure. We love him a lot on this side of the pond too!

[@Sungodv]

he is an American, but it's OK for other nations to admire his work

[@tommyvega7948]

@@Sungodv Thanks for the permission. Jokes aside, "American Treasure" doesn't mean he's from America, but that he's a treasure TO America. To which I add: he's a treasure for the whole world

[@areligaming6263]

I just want to listen to Dan all day

[@rakentrail]

Dan, I had a customer that didn't want to see the "dot" on his ebony bridge so I drilled a plug out of some scrap ebony with a plug cutter. I aligned the grain when I glued it in. Pared off the excess and sanded smooth. A bit of lemon oil and, "POOF" it disappeared! LOL!

[@georgelackey622]

I've got one on the bench right now, an old 70's Yamaha. Been using them for awhile, great fix for a bellied up acoustic.

[@terrynorton3182]

I have a bad belly on my Epiphone but I can’t see how this will help with a belly up?

[@George-gj9me]

@@terrynorton3182 Imagine you are hanging from a rope which is attached to the ceiling of a small room. you decide you want to pull the ceiling down so you put your legs up on the wall and pull down. This is what it is doing

[@guitartec]

I've installed so many bridge trusses over the last 20 years, that when the patent ran out, I started making my own much more durable version. The JLD truss has lots of problems stripping out the adjuster screw because it threads into nylon under intense pressure. Mine uses T-nuts and a metal threaded rod. It works great for all low-end to mid-priced acoustics, especially 12 strings and acoustic basses. My '37 Martin has one too... It's amazing and no neck reset is necessary.

[@sumljivi]

Can you send me your info and price on your bridge doctor. Does it make acoustic guitar lose volume at all?

[@MrStewPedaso]

I also would like more info and pricing on your product. Thanks.

[@mcouzijn]

@@sumljivi On the contrary, a JLD Bridge Doctor actually enhanced the sound of my flat-top (a fine 1969 Rokkomann). Its volume particularly increased with respect to the lower strings. I suppose that just like the 'sound post' in violins or cello's (a wooden dowel under the bridge connecting the top with the back of the violin) it transports the vibration from the bridge to the body of the guitar by means of that long dowel that is under tension.

[@DaveBricker]

I've worked with bridge systems ("doctors") for many years. Yes, it looks like it would kill the vibration of the top, but in reality, it's the opposite. Think of the bridge as a voice coil in the center of a speaker. The stiff part is at the center (because the cone is stiffer where it;s smaller) and various frequencies are released from the cone at the appropriate distances from center. Put that same voice coil on a flat panel and you'll get phase shifts, standing waves, etc. By forcing the bridge to move primarily up and down, you eliminate all the chaotic top vibration. Not only does the bridge become the stiffest part, some of the string energy gets distributed to the tailblock via the back and sides. You'll feel more vibration all the way to the headstock and you can hear (and measure) a dramatic increase in sustain, bass, and volume. In my experience, cheap guitars benefit most, but I put JLD systems in new high-end guitars, too. If the guitar is lightly built and resonant already, the tonal effects are negligible, but the top will remain flat forever. Hang 120 pounds of string tension on a guitar top and it WILL, with 100% certainty, warp sooner or later. The JLD fixes that problem and is a remarkable tone enhancer. I've probably installed 50 of them and never once have I been disappointed.

[@dannyboy9978]

Ditto to everything you said. I've installed dozens of these and they work. Don (the man who invented & mfrs these) is a generous wealth of knowledge. I've been working on guitars for over 40 years, but 15 minutes talking to him taught me stuff about acoustic guitars that I might never have discovered since I'm an electric specialist.

[@rafaeloda]

Hi, good input. Do they (bridge docs) last long or they need to be replaced with time?

[@juansantana9678]

Very true it actually adds more sustain

[@christurnblom4825]

Nice! Is there any preferred wood grain direction if I were to make one? I have an 1970's Ventura 12 string which looks like it's brand new new except that it has this problem. I'm a machinist and have 20 years of hobby experience, repairing & rebuilding guitars so I don't think I'll screw up making the thing.

[@guitarajoseph]

Breedlove's tend to come with this. It has its pros and cons but overall I like the feature

[@lyonthomas5254]

Hello can anyone explain the importance of the pivot hole (nylon and screw) being on the limit of the bridge. The outer ledge of the bridge of my Dorado is too small and drops off too sharply to place a screw hole. I am seriously thinking of placing it near the saddle like Dan did for this Gibson. If he did it...I noticed he put his nylon thingy on the first hole.

[@DougHinVA]

I had a Samick dread that had a 'belly' and the 12th fret string gap was too high. I considered Bridge Doctor (about $25), but tried the obvious first: The guitar was probably neglected and far too dry. Fret ends were sharp and needed filing down, the guitar had no case, was in good cosmetic shape and had old strings put on by a ignorant person. All together, maybe just a damp sponge on waxed paper inside and close off the soundhole would help. I set a small paperback (protect finish) and 2 pairs of pliers on the bulge (small weight as humidity was restored). By day 3 the bulge is nearly gone. Clean and lube the old 'covered back' tuners and get a bone saddle and just live with the plastic nut but deepen and neaten the slots with files. Small job and the $50 guitar can be sold for probably $80 when I get it ready by the weekend upcoming.

[@pcas96]

Thanks I'm just beginning amazing work

[@MrStewPedaso]

I fixed my 1983 Fender Balboa the same way. Only difference is I plugged the screw hole in the bridge with a small round piece of ebony (the bridge looks like ebony). Makes it vertically invisible. Gave my old guitar many more years of life.

[@mandoanne9466]

I don’t see any comments on here about humidity, or lack, which is what causes these problems to begin with. I live in the high desert in New Mexico. Relative humidity usually in the teens and 20’s. I forgot to humidify my guitar (mostly because I now play more mandolin), and here’s my “diary” of healing my guitar recently: Yamaha FG-335E (acoustic with electric pick-up) 1/25/2023 Brad & Luther looked at my guitar & suggested Galen take a look. 1/27/2023 Galen took a look and said my guitar is begging for humidity and it’s about to explode if I don’t do something immediately. I humidified it that night. He said soak a towel and put it in a plastic bag in the sound hole and in the case for a month! He said my Yamaha is top-of-the-line for the year it was made and deserves a really good effort. I put 2 small bowls with a soaked sock in each one, with a drop of frankincense. Covered the sound home with a plastic cover and locked the case. 2/1/2023 added more water to bowls. 2/9/2023 added more water to bowls. 2/10/2023 added cutting boards at bridge end to add weight per Galen’s recommendation. He recommended a telephone book but I wouldn’t be able to close the case so I used small cutting boards. 2/17/2023 added more water to bowls. 2/21/2023 Galen inspected, measured, and said he sees improvement. He showed me how the wood shrank and the frets didn’t, and are sticking out. But he said it’s progressing nicely and needs more time humidifying. He said when I put new strings on, don’t use first string with diameter any higher than .11. The others will be .14, .22, .38, etc. He suggested looking at KZbin video by Bridge Doctor. Might need to drill a hole as he did with his guitar, to put like a truss rod similar to the truss rod inside the neck, but at the bridge end. Added more water to bowls at home and replaced cutting boards.

[@edyue1]

TLDR 🤣

[@jim9637]

The instructions tell you to first drill the 1/4" hole, which will be flat bottomed, and then the smaller hole for the screw. The screw was actually slightly larger than the 1/4" hole so I had to grind down the screw head so it would fit into the hole. The screw is a flat head with beveled sides, as all flat heads have, so you have a flat bottom hole for the beveled head. It seems to me that the screw will possibly split the bridge so I used a regular bit to counter sink the smaller hole. I think they should supply a round head screw instead. Has anyone else had this experience?

[@jixxxxer17]

wow this was just a brilliant video, thank you so much for posting ! did you change to the brass bridge pins too or no ? Peace !

[@twistedxknights]

could something like this be used for a ukulele with a bridge belly problem?

[@oliviavaldez3379]

So I've installed the bridge doctor, but I'm not sure if the brick or wood box should move slightly under the bridge

[@thegee-tahguy4877]

Man, you could rip out the rest of the cross brace. The bridge truss can support that entire top and then sum. It's a brilliant device that unfortunately isn't made well (the threaded insert often strips out of the nylon tube upon initial threading). I make one that uses 1/4-20 T-nuts and uses threaded metal rod that is more utilitarian, but gets the job done and lasts forever. Works great in old Yamahas and similar.

[@mikearcuri406]

Instructions say to drill behind the bridge pin holes. Dan had no choice on the 12 string but to drill in front of the holes because he had no room behind. If you drill behind the holes, you can’t encroach too far forward or your D and G bridge pins will hit the plastic post and not seat properly. The leading edge of the 1/4 inch hole needs to be at least 1/16th in. behind the rear of the D and G bridge pin holes to prevent this. This is not mentioned in the instructions.

[@michaelpthompson]

Dan Erlewine is still the master of guitar repair. I have a 12-string I could use this on.

[@jakejuntilla1752]

Is there any alternatives to anyone who doesn’t have access to bridge doctor or thompson belly reducer?

[@mick0248]

will this work with a floating bridge 12 string guitar where the top has dipped?

[@rheybusque9752]

Hi there sir, I have a guitar with a bridge similar to Gibson L-0, and not much real state to find a place to make the drill. Any suggestions on where on the bridge should I drill? Thank you

[@Azuresilver]

I like these videos a lot of work but i'd really like to see start to finish.

[@jmchessor]

I'm looking at a '64 J45 that needs this type of repair. If you don't mind, what does a repair like this cost? And how does it affect the value of the guitar? Thanks

[@mattderynioski1434]

Looking at doing this to a 70s Epiphone MIJ 12-string. Should the belly be flattened out with clamps first or can the Bridge Doctor go in, belly and all?

[@danatompkins4385]

What would it be like if you didnt need the X brace? Would that open up possibilities to get more sound?

[@drvnlp6269]

I like the way StewMac censors negative product reviews on their website for products they sell to make customers think everything they sell is wonderful.

[@HunnysPlaylists]

Do they do that?

[@zanfonero]

Te has ganado el cielo, amigo.

[@staticswitch]

Dan I have one question. I have many guitars. I have Ibenez 12 string guitar which i need to install a bridge doctor due to the way I am going set it up. It’s going to have a lot more tension. If I have a 12 string, and I get the Brass pIn JDL bridge doctor, how come it only comes with 6 brass pins? I just want to say that I am learning how to work on guitars and want to take good care of my guitars. Thanks , Javier - Yuba City California

[@jakelencher817]

i have an old acoustic that has this goin on pretty bad, was wondering how you fix this.

[@richw.6296]

Hello all, does anyone know what size tuner bushings to use on my 1969 B-25? StewMac offers large and small.

[@heavymatelalive2804]

I have a takamine ef381c accoustic electric. Someone sat on the soundhole area and bent the bridge in qnd caved in the sound hole which misaligned the neck upward..Is there a chance for life??

[@jeffanderson8384]

I have a Breedlove 12 that has a bridge doctor installed (they come that way). Despite having the bridge doctor it still developed a really bad belly bulge and the bridge is pitching forward. Can the bridge doctor be adjusted to remedy this problem?

[@thegoodtest]

My issue is on the opposite side of the sound hole where the the neck is pushing down on the top which causes high string action.

[@radiojoehead]

How fix bridge belly, where top wood acoustic guitar is belly warp upwards just around and under bridge area??? I could put 2 quarters under 12 fret(11th and 12th fret wires) and there's still just enough space for 1 paper business card only with 2 quarters and business card touches strings. Is guitar unfixable? Should I move bridge 2-3 inches closer to sound hole where body is flat and NOT belly warping upwards for optimal action??

[@Obscurity202]

Can you use it on the other end of the body under the fingerboard with the neck block?

[@serajeddin9645]

Guys .. do you know if the bridge doctor will fit in a slim flamenco guitar ?

[@ariespanghulan3914]

Can I use jld bridge doctor in nylon guitar?

[@RockStarOscarStern634]

It's basically a Guitar version of a Soundpost for Bowed Stringed Instruments. Bowed Stringed Instruments use a Soundpost to help keep the top from collapsing.

[@tresstandifer7397]

My classical guitar is made by Kujiyama model 818, and the Bridge Doctor I have is the #AN3694, there is a brace on the back inside the guitar where the Bridge Doctor needs to go, and it is stopping me from installing the Bridge Doctor, is there anything I can do to be able to install the Bridge Doctor?

[@blackfly1955]

Would you recommend doing this to a 1979 D-35? Still on the first bridge and I'd rather not have to drill a hole in the plate.

[@jonnramos1247]

what does a colapsed top do to a guitar? does it affect the sound of the guitar?

[@Nigelv]

Mine is in the mail for my dad's 12 string☺

[@jonahguitarguy]

Now you crossed the line Dan. All the old Grassers I do repairs for think the bridge Docs are an abomination. I think they're great and don't take away from the tone at all. In my experience they some times increase the guitars volume.

[@chrispile3878]

Impossible that they would increase volume and improve tone. Physics doesn't agree with you.

[@jonahguitarguy]

I said nothing about improved tone. And they did increase volume and several others that I read about said the same thing. Not always but sometimes.

[@dannyboy9978]

"Physics " once said that no wheel driven vehicle could do a 1/4 mile drag in less than 8 seconds or faster than 200mph. Then along came drag racers, who broke 8 seconds in 1963. And Don Garlits, who was the first to 200, 240, 250, and 270 miles per hour. The 1/4-mi record now stands at 4.45 seconds at 336mph. My point being that science is NEVER settled. Guitars have been scientifically measured getting louder after Bridge Doctor installs. And tone is too subjective to quantify. Breedlove is not alone in putting them in brand new guitars.

[@544w71]

I can testify that the JLD is a great fixit for not only a bellowing bridge and the top, but It actually makes any guitar sound better, warped top or not! I only wish I could have installed my bridge doctors this easy, with a cutaway guitar :). :)

[@crabtrap]

any tips on the reverse problem? I have a extreme high humidity acoustic that has a bulged soundboard in the whole bridge area to the tail edge. it of course has raised the action

[@stewmac]

The JLD Bridge Doctor is the perfect thing to correct bulging, referred to as "bellying", in the soundboard around and behind the bridge. It's actually more common for the JLD Bridge Doctor to be used for this kind of repair. The repair featured in this video is pretty unique in comparison.

[@alal6964]

This is what we called guitar GOD...he can fix any guitar

[@Iranianjunkie]

Yeah this is awesome

[@martindanburen1994]

hmm. I'd imagine it dampens the top vibrations quite a bit. How much did the sound change from this addition? but then I suppose the re-bracing they did alter the sound as well. lol. Better you than me. Congrats on successfully bringing this 12 string back.

[@JJDoole]

I put one in my 12-string when the bridge was pulling the top up. Sure, it brought the top back down, but it killed the tone; too much bass, reduced mids, and reedy highs. I put up with it for a few months and then got fed up with it and took it out. To my surprise, the top held in position. That was 6 years ago.

[@mattstacy1652]

What if the top is sinking at the sound hole right at the end of the fretboard.

[@avt3216]

Did it. Absolutely kills the tone. No more bass.

[@johnmckenna6203]

The Bridge Doctor is always a last resort kind of thing just to get a guitar playable again. They definitely do work but they also change the tone of the instrument. Some claim that for their personal instruments the tone actually improved. So it's not necessarily a bad thing but it will change it.

[@stephencastro1437]

You are the only person I have found that stated there was a drop in tonal quality when installed. I installed one where I had re-glued the bridge to give added relief and to help in preventintg future problems. After re-glue guitar sounded amazing. I just recently installed the Bridge Doctor, and it killed the tone. I'm not talking about a slight change, I'm talking HUGE! You are correct in saying it should be considered as a last resort option for extreme bulge repairs. I'm going to remove it from the repair I mentioned. But I do have to use one for another serious repair on a 12 string. I Thanks for the comment.

[@onusgumboot5565]

@@stephencastro1437 I'm glad I ran across these comments. I was wondering about how it would affect the tone. It seemed like it would have to affect it pretty drastically to me. It just about has to stop the top from vibrating the way it should. I was considering it for my old '67 J45. It was pretty beat up when I got it, but it sounds great. I don't think I would like the change. I'll just keep playing it like it is until I can't anymore. It actually plays fine, it just looks rough, and I'm sure it will get worse eventually.

[@VadimLyutiy]

@@stephencastro1437 the main thing killing 12-string guitars is a 0.012 strings.... I was so stupid to set ones replacing old 0.010, thinking to get fat sound. Yes, i got the sound, but after a month my bridge changed the angle and upper bout got curved lifting the strings on 2mm... now trying to find a way to curve all back...

[@big_fat_hen]

@@VadimLyutiy Down tune the guitar and use a capo is the only way to go if not played often. And yes lighter strings.

[@VadimLyutiy]

@@big_fat_hen yes sir, even with the stuff you mentioned done(capo and tune drop both), it lifted up ((

[@waynedavies3185]

That works on a regular sized acustic guitar that has plenty of room for the bridge doctor, I work on some of the older parlor type guitars (sold back oin the 1940's and 50's that are much thinner than a regular full size guitars. The bridge doctor will not fit in them, least the way you folks make them. They are too large and won't fit properly inside due to the guitar bracing and overall width/thickness of the guitar in question. Any repair ideas regarding these type of older guitars in repairing their warps.?

[@darrelllancaster8675]

Does the sound change with a bridge doc?

[@williambrady7718]

The device works to an extent but does not perform miricles. The device evens the area in front of the bridge with the area behind the bridge. What it doesnt do is lower the whole face of the guitar. Over time the Face has become convex instead of flat. There are two problems created by the belly. The twisting forward of the bridge and the lifting of the whole face. This device only corrects one of them the twisting of the bridge. I have a Yamaha FG312. Over time I have shaved the saddle down to copansate for the rising bridge. it got to the point where there was no saddle left. I installed the bridge doctor and it brought the guitar back to playable but not so much that I could get a new saddle and had to raise the action.

[@rudolfprinsloo3299]

Is there not a chance that this device will cause vibrations or rattling sounds?

[@GrumpyTy34er]

I bought a cheap guitar with the exact same problems that you just mentioned. Hopefully, I can do the same thing and make it work. I'll just need to find some stronger support and maybe make or purchase my own bridge doctor Edit: well I’ll probably actually buy it for one guitar and then have to make it for my shallow 2 inch body guitar.

[@josephmeredith7436]

Dang! That is one sweet invention! Problem solved. Cheers

[@ssf3463]

How much does it cost to get one of these baby's installed?

[@joehannsson]

I need this fix...

[@anitborabo3214]

Yeah i like the way you cook

[@s1bee]

Wow! Great ways...

[@fleadoggreen9062]

Anyone ever try to remove the bridge doctor after like a year or two, see if the guitar is no longer warped

[@arturomomo]

Beautiful how it works! Doesn´t it add a significant amount of weight to the top?

[@chrispile3878]

Yes. Too much weight.

[@stewmac]

The screw mount JLD Bridge Doctor weighs just shy of 2oz, and the brass pin mount JLD Bridge Doctor weighs just under 3oz.

[@LongTrout]

Has anyone had good luck with removing the bridge doctor after a year with proper humidification and having the soundboard hold?

[@Larry-Art179]

sound killer

[@theoforde-stiegler]

The bridge doctor is basically the same idea as Breedlove's bridge truss, yes?

[@sighfactor]

He's the Bob Ross of Guitar Repairs

[@mwarnken1234]

so you didn't use the 12 string version with the pins, and you also put the hole much closer to the saddle than the instructions say to do... i didn't realize there was that much flexibility with the installation...

[@beenaplumber8379]

My friend has a "relatively" inexpensive concert classical guitar, rosewood back & sides & cedar top, and a terrible belly wave on the top. It can't be tuned higher than 3 half-steps below standard tuning. The action is extremely high, nearly unplayable. He doesn't want to pay for a repair. (To him it's an ornament.) Would this be an appropriate repair? Would it preserve the guitar's unusually loud resonance? How would it affect the guitar's value? (It's old, probably handmade, but nearly worthless in its current condition. Again, to him it's an ornament, a wall-hanging.) I'd appreciate replies from anyone who has used this repair. Thanks!

[@goootar]

Wow... that's a fantastic idea. If I would have known about this 10 years ago I might have been able to "fix" my 12 without destroying the bridge (to lower it). Does anyone know of a way to change the angle of the neck? So the strings would be raised higher down by the bridge. Not the truss rod --- that just changes the warp if any. I need to change the whole angle

[@stewmac]

To change the neck angle on your guitar, you will need to do a neck reset. Once the neck has been removed from the body, you would then remove wood from the upper portion of the heel. This will reduce the neck's angle, causing the string action to raise. However, a simpler fix may be to replace the saddle on the bridge with a taller one.

[@goootar]

Thanks, The neck was pulling away from the body -- caused by string tension and pull -- so the strings were too high above the fretboard and I kept lowering the size of the saddle with a smaller one but it eventually bottoms out. So when I said "raise the strings down by the bridge" that meant have normal action above the fretboard but the angle will be higher at the bridge so a taller saddle can be installed. I'm not sure if I worded that correctly? The neck reset will of course work. Then I can put a regular height saddle back in and I will get my nice tone back from the under-the-saddle sensor pick-up. The "heel" is part of the body? I was looking for a diagram of what wood needs to removed relative to how you want to change the string height and saddle

[@dannyboy9978]

Before you do a neck re-set you need to find out where the strings would wind up with the neck firmly set into its joint. It may not need a re-set. With a normal properly adjusted, non-defective guitar, if you put a long straight-edge standing on edge on the frets and slide it towards the bridge, the bottom of the straight-edge should wind up at approximately the same level as the top surface of the bridge (at the base of the bone saddle). If it's more than about 1/8" below the top of the bridge you either have to cut down the top surface of the bridge or more complicated repairs to get the top of the saddle low enough for correct action. You said it pulled away from the body - I'm assuming the heel is pulled and you can see a gap from the side. This is very common. I've repaired dozens of these over the years. The method for repairing it depends on how much work needs to be done vs. the value of the guitar. Just removing the neck & re-gluing properly can be a few hundred bucks, depending on the construction. Many low end guitars don't use a dovetail joint, but rather several wooden dowels from the heel to the body. You don't want to try to remove those unless all the glue has failed and/or dowels have broken. I've seen this. If it's a valuable guitar and it really needs a neck reset, be prepared to spend up near $1,000 for it to be done right. If it's a lower-end guitar, another method is to drill thru the neck block from the inside, out to the neck heel and install a screw after shooting as much glue in the joint gap as possible. It works.

[@goootar]

It is a Suzuki Nagoya sf 312 12-string guitar. When I look in the sound hole there is a block up by the neck. The neck itself is separate from that, correct? So your idea might work. I will drill a hole from bottom (closest to the back of the guitar) out to the neck the put a screw or long nut and bolt and tighten. That might work. It will be tension opposite the pull of the strings which has caused the problem. It might be better to start drilling from the heel on the outside -- then I can line it up perfectly. Thanks

[@thiagogoncalves3579]

But this will not "lock" the top, reducing the sound of It?

[@andrewking3016]

This guitar is currently listed for sale on Reverb.com. Check it out: reverb.com/item/41363853-1964-gibson-b-25-12-natural

[@Samos12]

This looks great, but how the heck do I flatten my top before this step???

[@stewmac]

Does your guitar's top just have bellying behind the bridge, or is the top warped like a wave similar to the original state of the guitar in this video?

[@Samos12]

Similar to this guitar...

[@tonygombas491]

Very clever 🤔

[@askwho69]

Genuis

[@HN-lh9vs]

It would have been helpful to note that there are three possible locations for the nylon post. I typically use the greatest spacing possible such that the wooden tongue still contacts the bridge plate. Other than maximizing the lever arm I don't have any good rationale for following this approach...

[@lyonthomas5254]

Yes I would be interested in knowing the difference. My guitar, like this Gibson has no room on the edge and I am thinking of doing what Dan did ie putting it near the saddle. I have no idea if it changes something.

[@jim2mars]

I added the Bridge Doctor to a 1972 Horner 12 string to fix the Belly. Worked great and improved the tone vastly. Then at put a Bridge Doctor in a 1978 Guild F212NT 12 String. The result was amazing, way more bass and better tone over all. I had a chance to talk to the inventor years ago, great guy and very helpful. for more info: jldguitar.net/

[@jasonorafferty344]

Key words if it holds there

[@mickavoidant4780]

Good job most acoustic guitars have one big sound hole

[@alext9067]

As good as the Bridge Doctor is at solving this problem, does it create a new one? As much as some might think that the strings vibrating over the sound hole make the big sound, It's just the opposite. By hook or by crook, the vibrations of the strings are transmitted to the top plate and the bridge doctor is impeding those vibrations. Archtops were created to solve the problem of collapsing top plates, but they fell out of favor and this created a problem. Any solution that fortifies the top against deflection mutes the transmission of sound. How does a violin do it? How can a 16th century Amati still play well and a 20th-century guitar fail to do so? I think it's doing two things that you won't like. One is to design the top so that it's in compression and transmitting force to the bouts. The second is to install a soundpost. I'm not crazy about either one, but that's what a violin does. And a tiny violin can fill a theater with a very loud sound. It's very insane. I'll just add that Spanish guitars don't have either of these things and can blast out a great amount of sound. I don't know how long they can remain undamaged, but they do the job, somehow. Interesting puzzle.

[@waynedavies3185]

I'd like nto se you insert this Bridge doctor int a 3 1/4 inch thick Old Parlor Concert type guitar from the early 40's and 50's. I have been able to pickup a few of them and got them back into playable condition againg after the past owner gave up on them and gave them away as wall hangers. I once in awhile get one that is in near perfect playable condition except for the fact that the top is wrapped. It's bellied behind the bridge, and leaning downward in front of the bridge. The Bridge doctor as they are made by Stewmac won't fit inside properly to correct the issue. Due to thick bracing inside and the size of the doctor itself, they don't fit and correct the problem. Even with a small amount of wrappage on the top they won't fit inside correctly. Regular sized thickness of an acoustic is 4 inches thick which the doctor fits in snugly, but with the loss of 3/4 of an inch in thickness, these bridge doctors are no good for these smaller thinner sized guitars (even Ukuleles of the same style of thickness) where the tops have warped. Do they make a smaller sized Bridge doctor for these types of instruments? If so where can I find and purchase them? It would be interesting to watch you flatten the top of one of these instruments in a video. Some are worth saving, even though they are cheap to buy new.

[@johnhodges8264]

What I don't understand why people with bowed out tops don't fit a tail piece which totally pushes the bridge down and after time the top will be flat again and the tailpiece can the be removed.

[@dannyboy9978]

There is no such thing. Trapeze tailpieces for acoustics screw onto the tail-end which means screw holes that don't belong on a round-hole guitar. Besides, they don't exert any significant downward pressure on the bridge or the top of the guitar. The difference in height between the top of the saddle and the part of a tailpiece where the string attaches is a small fraction of an inch. While doing this will remove upward/forward tension from the bridge, it will result in very little downforce on it. The most common example of this is the cheap 12-strings from south of the border. They work, and they almost never warp, but they have a tiny voice. Archtop guitars can use trapezes because the arch makes the height difference large enough to apply significant downforce.

[@kowal767]

Is anybody try to make own Bridge Doctor? 50$ Canadian is too much.

[@stephencastro1437]

How much (how many times) do you have to tighten the set screw? The instructions that come with the kit don't explain this, nor do any of the videos posted on KZbin.You make a reference to over tightening but don't explain any further. It seems to be a critical step to skip in my opinion and I came to you as a last resort as I'm doing the same repair on 2 guitars and I can't find a definitive answer. You allude to over tightening, but don't explain any further. Also, my instructions tell me when inserting the tension rod, the tapered (pointy) end should face the soundhole and against the tension set screw. I'm really getting frustrated as I keep seeing it done differently. I would greatly appreciate some help. Thank you